Phase 1 — NPLEX Part II Clinical Cases

NPLEX Part II • Phase 1 • Clinical Case 1

Acute ST-Elevation Myocardial InfarctionClinical Case 1

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 59-year-old man presents with severe central chest pressure that began 45 minutes ago while shovelling snow. The pain radiates to his left arm and jaw. He reports diaphoresis, nausea, and shortness of breath. Medical history:

Hypertension
Type 2 diabetes
Dyslipidemia
Tobacco use: 30 pack-years Medications:
Metformin
Losartan
Atorvastatin Vital signs:

BP: 152/94 mmHg
HR: 104/min
RR: 22/min
SpO₂: 95% on room air ECG demonstrates ST-segment elevation in leads II, III, and aVF.

Q1

What is the most likely diagnosis?

AAcute pericarditisBInferior ST-elevation myocardial infarctionCStable anginaDPulmonary embolismEGastroesophageal reflux disease

Reveal answer and rationale

✓Correct answer: B. Inferior ST-elevation myocardial infarction

Prolonged pressure-like chest pain, autonomic symptoms, and ST elevation in leads II, III, and aVF indicate an acute inferior STEMI. Why the Other Options Are Incorrect

A. Acute pericarditis: Usually produces diffuse ST elevation and positional or pleuritic pain.
C. Stable angina: Usually resolves with rest and does not cause persistent ST elevation.
D. Pulmonary embolism: May cause chest pain and dyspnea but does not typically produce this regional ECG pattern.
E. GERD: Does not explain regional ST-segment elevation.

Q2

What is the most appropriate immediate action?

ASchedule an outpatient exercise stress testBAdminister an antacid and reassess after 30 minutesCActivate emergency cardiac care and arrange immediate reperfusion assessmentDRecommend magnesium supplementationEBegin a two-week elimination diet

Reveal answer and rationale

✓Correct answer: C. Activate emergency cardiac care and arrange immediate reperfusion assessment

STEMI is a time-sensitive medical emergency. Emergency transfer, continuous monitoring, antiplatelet therapy when appropriate, and rapid assessment for reperfusion are priorities. NPLEX Trap Do not delay emergency transfer to obtain outpatient laboratory testing or initiate naturopathic treatment.

Q3

Which medication is generally administered early when acute coronary syndrome is suspected and no contraindication is present?

Reveal answer and rationale

✓Correct answer: A. Aspirin

Aspirin inhibits platelet activation and is a foundational antiplatelet medication in acute coronary syndrome when not contraindicated. Why the Other Options Are Incorrect

B. Warfarin: Is not the routine initial antiplatelet treatment for acute STEMI.
C. Digoxin: Does not treat acute coronary thrombosis.
D. Verapamil: Is not routine initial STEMI treatment and may be harmful in some patients.
E. Hydrochlorothiazide: Treats hypertension but does not address acute coronary occlusion.

Q4

The patient reports taking high-dose garlic extract and ginkgo. What is the most important concern?

ASevere hypercalcemiaBIncreased bleeding risk when combined with antithrombotic treatmentCAcute urinary retentionDReduced thyroid hormone productionESevere hypoglycemia in all patients

Reveal answer and rationale

✓Correct answer: B. Increased bleeding risk when combined with antithrombotic treatment

Supplements with potential antiplatelet effects should be documented because they may contribute to bleeding risk when combined with prescribed antiplatelet or anticoagulant therapy.

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Diagnosis: Inferior STEMI

Key differentials

Aortic dissection
Pulmonary embolism
Acute pericarditis
Pneumothorax
Esophageal rupture
GERD

Key investigations

Immediate 12-lead ECG
Serial cardiac troponins
CBC
Electrolytes and renal function
Blood glucose
Coagulation testing
Echocardiography when indicated

Treatment principles

Emergency activation
Cardiac monitoring
Antiplatelet treatment when appropriate
Rapid reperfusion assessment
High-intensity lipid-lowering therapy
Secondary cardiovascular prevention

Botanical medicine: No botanical treatment should delay reperfusion or emergency cardiac care.

Nutrition and lifestyle after stabilization

Smoking cessation
Cardioprotective dietary pattern
Cardiac rehabilitation
Blood-pressure management
Diabetes management

Pharmacology safety: Ask about aspirin allergy, active bleeding, anticoagulants, erectile-dysfunction medications, and supplements that may influence bleeding.

Clinical Pearl: Normal oxygen saturation does not exclude myocardial infarction.

NPLEX Trap: Do not order a stress test during an active STEMI.

Reference basis: Current acute coronary syndrome guidance emphasizes rapid emergency treatment, antiplatelet therapy, and timely revascularization.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 2

Severe Acute Asthma ExacerbationClinical Case 2

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 27-year-old woman with asthma presents with progressive wheezing and shortness of breath after visiting a home with several cats. She has used her salbutamol inhaler six times without sustained relief. Vital signs:

BP: 136/82 mmHg
HR: 124/min
RR: 32/min
SpO₂: 89% on room air Physical examination:
Speaks in short phrases
Uses accessory respiratory muscles
Diffuse wheezing
Markedly reduced air entry Peak expiratory flow is 35% of predicted.

Q1

What is the most likely diagnosis?

AMild asthma exacerbationBSevere acute asthma exacerbationCPanic attackDAcute bacterial sinusitisEStable chronic asthma

Reveal answer and rationale

✓Correct answer: B. Severe acute asthma exacerbation

Hypoxemia, tachypnea, accessory-muscle use, difficulty speaking, and severely reduced peak expiratory flow indicate a severe exacerbation.

Q2

What is the most appropriate immediate management?

AOral antihistamine aloneBBreathing exercises followed by dischargeCOxygen, repeated rapid-acting inhaled bronchodilator treatment, systemic corticosteroid, and urgent transferDLong-acting beta₂-agonist monotherapyEBotanical steam inhalation

Reveal answer and rationale

✓Correct answer: C. Oxygen, repeated rapid-acting inhaled bronchodilator treatment, systemic corticosteroid, and urgent transfer

Severe asthma requires immediate stabilization and emergency medical management.

Q3

Which finding suggests impending respiratory failure?

Reveal answer and rationale

✓Correct answer: C. Drowsiness with very poor air entry

Altered consciousness and a nearly silent chest may indicate critically reduced airflow and respiratory exhaustion.

Q4

Which botanical product is most concerning in this patient because of additive sympathomimetic effects?

Reveal answer and rationale

✓Correct answer: B. Ephedra sinica

Ephedra has sympathomimetic activity and may worsen tachycardia and cardiovascular adverse effects, particularly when combined with beta-agonist treatment.

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Diagnosis: Severe acute asthma exacerbation

Key differentials

Anaphylaxis
Pulmonary embolism
Pneumothorax
Pneumonia
Vocal-cord dysfunction
Acute heart failure

Key assessments

Airway
Respiratory rate

Oxygen saturation
Ability to speak
Accessory-muscle use
Peak expiratory flow when feasible
Mental status

Treatment principles

Oxygen for hypoxemia
Repeated rapid-acting inhaled bronchodilator
Early systemic corticosteroid
Emergency escalation when severe features are present

Long-term management

Inhaled corticosteroid-containing therapy
Trigger assessment
Inhaler-technique review
Written asthma action plan

Nutrition and lifestyle

Avoid known triggers
Smoking and vaping cessation
Address obesity when present
Treat relevant occupational exposure

Pharmacology safety: Repeated beta₂-agonist therapy may contribute to tremor, tachycardia, and reduced serum potassium.

Clinical Pearl: A silent chest can represent worsening obstruction rather than improvement.

NPLEX Trap: Do not substitute botanical medicine, hydrotherapy, or breathing exercises for emergency stabilization.

Reference basis: GINA identifies severe exacerbation features and supports urgent bronchodilator, corticosteroid, oxygen, and escalation strategies.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 3

Diabetic KetoacidosisClinical Case 3

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 23-year-old woman with type 1 diabetes presents with vomiting, abdominal pain, excessive thirst, and progressive fatigue. She developed influenza-like symptoms two days ago and stopped taking insulin because she was not eating. Vital signs:

BP: 96/62 mmHg
HR: 118/min
RR: 30/min and deep
Temperature: 38.1°C Laboratory results:
Glucose: 25 mmol/L
Sodium: 131 mmol/L
Potassium: 5.5 mmol/L
Bicarbonate: 11 mmol/L
Venous pH: 7.18
Serum ketones: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Diabetic ketoacidosis

Hyperglycemia, ketonemia, metabolic acidosis, dehydration, abdominal symptoms, and deep respirations are characteristic of DKA.

Q2

What is the most appropriate initial treatment priority?

AOral glucoseBIntravenous isotonic fluid resuscitationCSodium bicarbonate for every patientDLong-acting insulin onlyEHigh-potassium supplementation before laboratory review

Reveal answer and rationale

✓Correct answer: B. Intravenous isotonic fluid resuscitation

DKA commonly produces major fluid deficits. Initial management includes fluid resuscitation, followed by insulin and carefully monitored electrolyte replacement.

Q3

Why can the initial serum potassium be elevated despite a total-body potassium deficit?

AIncreased gastrointestinal potassium absorptionBPotassium shifts from cells into extracellular fluid during insulin deficiency and acidosisCIncreased bone potassium productionDExcess aldosterone activityEIncreased intracellular potassium movement

Reveal answer and rationale

✓Correct answer: B. Potassium shifts from cells into extracellular fluid during insulin deficiency and acidosis

Serum potassium may appear normal or elevated even though urinary losses produce substantial total-body potassium depletion.

Q4

Which statement represents appropriate sick-day counseling?

AStop basal insulin whenever oral intake decreasesBContinue insulin according to the individualized sick-day plan and monitor glucose and ketonesCAvoid all fluids to reduce vomitingDReplace insulin with cinnamonEExercise vigorously to reduce glucose

Reveal answer and rationale

✓Correct answer: B. Continue insulin according to the individualized sick-day plan and monitor glucose and ketones

Stopping insulin during illness can precipitate DKA. Patients need individualized guidance regarding insulin, hydration, glucose monitoring, ketone testing, and indications for urgent care.

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Diagnosis: Diabetic ketoacidosis

Common triggers

Infection
Missed insulin
New-onset diabetes
Myocardial infarction
Stroke
Medication-related factors

Key investigations

Blood glucose
Serum or capillary ketones
Electrolytes
Venous pH
Bicarbonate
Renal function

Anion gap
ECG
Investigation for the precipitating cause

Treatment principles

Intravenous fluids
Insulin
Potassium monitoring and replacement
Treatment of the precipitating cause
Frequent biochemical reassessment

Botanical medicine: Botanical glucose-lowering agents are not substitutes for insulin in type 1 diabetes or DKA.

Nutrition: Resume appropriate nutrition after stabilization and resolution of the acute metabolic crisis.

Pharmacology safety: Potassium can decline rapidly after insulin treatment; therefore, frequent monitoring is essential.

Clinical Pearl: A high initial potassium level does not mean the patient has adequate total-body potassium.

NPLEX Trap: Do not stop insulin merely because the patient is not eating.

Reference basis: Current diabetes standards identify DKA as a hyperglycemic crisis requiring fluid, insulin, electrolyte management, and prevention-focused sick-day education.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 4

AnaphylaxisClinical Case 4

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 36-year-old woman develops generalized urticaria, throat tightness, wheezing, dizziness, and abdominal cramping 10 minutes after eating a dessert containing peanuts. Vital signs:

BP: 78/46 mmHg
HR: 132/min
RR: 28/min
SpO₂: 90% on room air

Physical examination reveals lip swelling, diffuse wheezing, and cool extremities.

Q1

What is the most likely diagnosis?

APanic attackBAcute urticaria without systemic involvementCAnaphylaxisDVasovagal syncopeEAsthma without an allergic reaction

Reveal answer and rationale

✓Correct answer: C. Anaphylaxis

Rapid development of airway, breathing, circulatory, gastrointestinal, and skin manifestations after allergen exposure is diagnostic of anaphylaxis.

Q2

What is the first-line medication?

Reveal answer and rationale

✓Correct answer: B. Intramuscular epinephrine

Intramuscular epinephrine administered promptly into the anterolateral thigh is first-line treatment.

Q3

What is the best response if symptoms persist after the initial epinephrine dose?

AWait one hour because repeat treatment is unsafeBRepeat intramuscular epinephrine according to emergency protocol and continue resuscitative careCGive an oral botanical tinctureDDischarge after the rash improvesEGive an antihistamine instead of further emergency treatment

Reveal answer and rationale

✓Correct answer: B. Repeat intramuscular epinephrine according to emergency protocol and continue resuscitative care

Persistent airway, respiratory, or circulatory manifestations require repeated emergency assessment and additional epinephrine according to protocol.

Q4

Which medication may reduce the response to epinephrine and complicate anaphylaxis treatment?

Reveal answer and rationale

✓Correct answer: B. Propranolol

Nonselective beta-blockers can complicate anaphylaxis by interfering with beta-adrenergic responses and contributing to bronchospasm.

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Diagnosis: Anaphylaxis

Potential triggers

Foods
Medications
Insect stings
Latex
Exercise-related triggers

Clinical features

Airway swelling
Wheezing
Hypoxemia
Hypotension
Urticaria
Angioedema
Gastrointestinal symptoms

Treatment principles

ABCDE assessment
Immediate intramuscular epinephrine
Emergency medical activation
Appropriate positioning
Oxygen
Intravenous fluids when indicated
Repeated epinephrine when required

Botanical medicine: No botanical medicine should delay epinephrine.

Nutrition and prevention

Confirm food triggers when appropriate
Allergen avoidance education
Emergency action plan
Epinephrine auto-injector education

Clinical Pearl: Skin findings may be absent in some cases; airway, breathing, or circulatory compromise remains critical.

NPLEX Trap: Antihistamines do not replace epinephrine.

Reference basis: Emergency anaphylaxis guidance identifies intramuscular epinephrine as first-line treatment and supports repeat dosing when serious symptoms persist.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 5

Sepsis Secondary to Acute PyelonephritisClinical Case 5

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 67-year-old woman presents with fever, confusion, right flank pain, and dysuria. Medical history:

Type 2 diabetes
Hypertension
Chronic kidney disease Vital signs:
BP: 82/50 mmHg
HR: 126/min
RR: 28/min
Temperature: 39.4°C
SpO₂: 93% Physical examination reveals right costovertebral-angle tenderness. Laboratory findings:
WBC: 18.9 × 10⁹/L
Lactate: 4.3 mmol/L
Creatinine: increased from baseline

Q1

What is the most likely diagnosis?

AUncomplicated cystitisBSeptic shock caused by acute pyelonephritisCRenal colic without infectionDViral gastroenteritisEChronic asymptomatic bacteriuria

Reveal answer and rationale

✓Correct answer: B. Septic shock caused by acute pyelonephritis

Suspected infection with hypotension, elevated lactate, altered mental status, and acute organ dysfunction indicates severe sepsis physiology with shock.

Q2

What is the most appropriate immediate management?

AOral cranberry extract and follow-up in one weekBEmergency transfer, cultures when feasible without delaying treatment, intravenous antimicrobials, and fluid resuscitationCOral antibiotics only with home observationDFluid restrictionEWait for urine-culture results before treatment

Reveal answer and rationale

✓Correct answer: B. Emergency transfer, cultures when feasible without delaying treatment, intravenous antimicrobials, and fluid resuscitation

Sepsis with hemodynamic instability requires urgent resuscitation and antimicrobial treatment.

Q3

Which finding best indicates acute organ dysfunction?

Reveal answer and rationale

✓Correct answer: C. Acute confusion and increased creatinine

Altered mental status and acute kidney injury indicate systemic organ dysfunction.

Q4

Which statement regarding cranberry is most appropriate?

ACranberry can replace antibiotics in septic pyelonephritisBCranberry may be discussed later for selected preventive situations but has no role as emergency treatment for septic shockCCranberry immediately reverses hypotensionDCranberry sterilizes the bloodstreamECranberry eliminates the need for cultures

Reveal answer and rationale

✓Correct answer: B. Cranberry may be discussed later for selected preventive situations but has no role as emergency treatment for septic shock

Preventive adjuncts must not be confused with treatment of an invasive infection or septic shock.

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Diagnosis: Septic shock secondary to acute pyelonephritis

Key differentials

Obstructed infected urinary tract
Renal abscess
Nephrolithiasis
Acute appendicitis
Cholecystitis
Pneumonia

Key investigations

CBC
Lactate
Electrolytes
Renal and hepatic function
Blood cultures
Urinalysis and urine culture
Imaging when obstruction or abscess is suspected

Treatment principles

Immediate emergency care
Intravenous fluid resuscitation
Early appropriate antimicrobials
Source identification and control
Vasopressor support when indicated

Botanical medicine: Botanical urinary products do not treat septic shock.

Nutrition: Acute resuscitation takes priority; nutrition is addressed after stabilization.

Pharmacology safety: Antimicrobial selection and dosing must consider renal function, allergy history, local resistance, and infection severity.

Clinical Pearl: Confusion may be an early sign of severe infection in older adults.

NPLEX Trap: Do not wait for culture results before initiating urgent treatment in an unstable patient.

Reference basis: Sepsis guidance emphasizes rapid recognition, antimicrobial treatment, hemodynamic resuscitation, and source control.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 6

Acute Ischemic StrokeClinical Case 6

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 72-year-old man develops sudden right-sided weakness and difficulty speaking while eating breakfast. His wife confirms that he was normal 40 minutes ago. Medical history:

Atrial fibrillation
Hypertension Medication:
Apixaban, although adherence is uncertain Vital signs:
BP: 178/96 mmHg
HR: 96/min and irregular
Glucose: 6.8 mmol/L Neurologic examination:
Right facial droop
Right arm weakness
Expressive aphasia

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute ischemic stroke

Sudden focal neurologic deficits involving the face, arm, and language strongly suggest an acute stroke.

Q2

What is the most appropriate immediate action?

ABegin outpatient physical therapyBActivate emergency stroke services and document the last-known-well timeCGive an herbal circulatory stimulantDObserve for 24 hours at homeESchedule an MRI next week

Reveal answer and rationale

✓Correct answer: B. Activate emergency stroke services and document the last-known-well time

Stroke treatment is time-dependent. The exact time the patient was last known to be neurologically normal affects eligibility for acute treatment.

Q3

What is the priority brain investigation?

Reveal answer and rationale

✓Correct answer: B. Noncontrast CT of the head

Urgent brain imaging helps distinguish ischemic stroke from intracranial hemorrhage and informs acute treatment decisions.

Q4

Which supplement is especially important to document because of potential bleeding concerns?

Reveal answer and rationale

✓Correct answer: B. Ginkgo biloba

Potential effects on platelet function are relevant when assessing a patient taking anticoagulant or antiplatelet therapy.

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Diagnosis: Acute ischemic stroke

Key differentials

Intracranial hemorrhage
Hypoglycemia
Seizure with postictal weakness
Migraine with aura
Brain tumour
Functional neurologic disorder

Key investigations

Immediate glucose
Noncontrast head CT
CT angiography when indicated
CBC
Electrolytes
Renal function

Coagulation assessment
ECG

Treatment principles

Emergency stroke activation
Determine last-known-well time
Rapid imaging
Assess eligibility for thrombolytic and endovascular therapy
Prevent complications
Initiate secondary prevention after classification

Botanical medicine: No botanical intervention should delay stroke imaging or reperfusion assessment.

Nutrition and rehabilitation

Swallow assessment before oral intake
Rehabilitation
Blood-pressure management
Smoking cessation
Cardiovascular risk reduction

Clinical Pearl: Always check glucose because hypoglycemia may mimic stroke.

NPLEX Trap: Do not give food, oral medication, or supplements before assessing swallowing safety.

Reference basis: Updated acute ischemic stroke guidance emphasizes rapid stroke-system activation, timely imaging, and expanded reperfusion assessment.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 7

Acute Upper Gastrointestinal BleedingClinical Case 7

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 64-year-old man presents with black stools, dizziness, and an episode of vomiting dark-red blood. Medical history:

Osteoarthritis
Hypertension Medications:
Ibuprofen 600 mg three times daily
Aspirin 81 mg daily
Amlodipine Vital signs:
BP: 88/56 mmHg
HR: 122/min
RR: 24/min Physical examination:
Pale
Diaphoretic
Epigastric tenderness
Black stool on rectal examination

Q1

What is the most likely diagnosis?

AAcute upper gastrointestinal bleedingBUncomplicated hemorrhoidsCIrritable bowel syndromeDAcute viral gastroenteritisEDiverticulitis

Reveal answer and rationale

✓Correct answer: A. Acute upper gastrointestinal bleeding

Hematemesis and melena with hypotension and tachycardia indicate significant upper GI hemorrhage.

Q2

What is the immediate management priority?

ATest for food intoleranceBHemodynamic stabilization and urgent hospital managementCBegin oral iron onlyDRecommend fasting at homeEGive a stimulant laxative

Reveal answer and rationale

✓Correct answer: B. Hemodynamic stabilization and urgent hospital management

The patient has signs of hemorrhagic shock and requires immediate emergency assessment and resuscitation.

Q3

Which medication most likely contributed to the underlying mucosal injury?

Reveal answer and rationale

✓Correct answer: B. Ibuprofen

Frequent NSAID use increases the risk of peptic ulceration and gastrointestinal bleeding.

Q4

Which botanical supplement would raise additional concern regarding bleeding?

Reveal answer and rationale

✓Correct answer: A. Ginkgo biloba

Potential antiplatelet effects may be clinically relevant when combined with aspirin or during active bleeding.

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Diagnosis: Acute upper GI bleeding, likely NSAID-associated peptic ulcer bleeding

Key differentials

Peptic ulcer disease
Gastritis
Esophageal varices
Mallory-Weiss tear
Malignancy
Esophagitis

Key investigations

CBC
Type and crossmatch
Electrolytes
Renal and hepatic function
Coagulation testing
Endoscopy after appropriate stabilization

Treatment principles

Airway assessment
Intravenous access

Hemodynamic resuscitation
Blood-product assessment
Acid suppression when indicated
Endoscopic diagnosis and hemostasis

Botanical medicine: Avoid supplements that may increase bleeding risk during active hemorrhage.

Nutrition: Oral intake may be restricted during acute stabilization and procedural assessment.

Pharmacology safety: Review NSAIDs, aspirin, antiplatelets, anticoagulants, corticosteroids, alcohol use, and supplements.

Clinical Pearl: Melena with hypotension is an emergency even when abdominal pain is mild.

NPLEX Trap: Do not treat acute blood loss with oral iron alone.

Reference basis: Upper-GI-bleeding guidance prioritizes assessment of hemodynamic status, resuscitation, risk stratification, and endoscopic management.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 8

Ruptured Ectopic PregnancyClinical Case 8

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 30-year-old woman presents with sudden severe left lower abdominal pain, dizziness, and light vaginal bleeding. Her last menstrual period was seven weeks ago. A home pregnancy test was positive. Vital signs:

BP: 84/52 mmHg
HR: 128/min
RR: 24/min Physical examination:
Marked lower abdominal tenderness
Guarding
Left adnexal tenderness

Q1

What is the most likely diagnosis?

AUncomplicated intrauterine pregnancyBRuptured ectopic pregnancyCPrimary dysmenorrheaDUncomplicated cystitisEEndometriosis without acute complication

Reveal answer and rationale

✓Correct answer: B. Ruptured ectopic pregnancy

Early pregnancy with unilateral pelvic pain, vaginal bleeding, peritoneal signs, hypotension, and tachycardia strongly suggests ruptured ectopic pregnancy with internal hemorrhage.

Q2

What is the most appropriate next step?

ARepeat a pregnancy test in one weekBEmergency stabilization and immediate gynecologic or surgical assessmentCBegin oral iron and dischargeDPrescribe an herbal uterine tonicESchedule routine prenatal care

Reveal answer and rationale

✓Correct answer: B. Emergency stabilization and immediate gynecologic or surgical assessment

Hemodynamic instability and suspected intra-abdominal bleeding require immediate emergency management.

Q3

Which investigation is central to evaluation in a stable patient with suspected ectopic pregnancy?

AChest radiographBTransvaginal ultrasound combined with quantitative beta-hCG assessmentCColonoscopyDPulmonary-function testingEEEG

Reveal answer and rationale

✓Correct answer: B. Transvaginal ultrasound combined with quantitative beta-hCG assessment

Pregnancy location is evaluated using ultrasound findings together with quantitative hCG trends and the clinical picture.

Q4

Which treatment would be inappropriate in this unstable patient?

AEmergency surgical assessmentBIntravenous access and resuscitationCDelaying care to begin botanical treatmentDBlood-product preparation when indicatedEContinuous monitoring

Reveal answer and rationale

✓Correct answer: C. Delaying care to begin botanical treatment

No complementary treatment should delay emergency management of suspected rupture and hemorrhagic shock.

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Diagnosis: Ruptured tubal ectopic pregnancy

Key differentials

Threatened pregnancy loss
Ovarian torsion
Ruptured ovarian cyst
Appendicitis
Pelvic inflammatory disease
Intrauterine pregnancy with another cause of pain

Key investigations

Pregnancy test
Quantitative beta-hCG
Transvaginal ultrasound
CBC
Blood type and Rh status
Type and crossmatch
Renal and hepatic function when medication treatment is considered

Treatment principles

Immediate stabilization when unstable
Urgent surgical management for rupture or hemodynamic compromise
Medical management only for appropriately selected stable patients

Botanical medicine: Uterine-stimulating herbs are inappropriate in suspected ectopic pregnancy.

Clinical Pearl: Shoulder-tip pain may indicate diaphragmatic irritation from intra-abdominal blood.

NPLEX Trap: A positive pregnancy test does not confirm an intrauterine pregnancy.

Reference basis: Ectopic pregnancy can become life-threatening and requires timely diagnosis and emergency surgical management when rupture or instability is present.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 9

Acute Bacterial MeningitisClinical Case 9

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 42-year-old man presents with severe headache, fever, vomiting, photophobia, and increasing confusion. Vital signs:

BP: 104/66 mmHg
HR: 116/min
RR: 22/min
Temperature: 39.6°C Physical examination:
Nuchal rigidity
Confusion
Photophobia
No focal limb weakness

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute bacterial meningitis

Fever, severe headache, neck stiffness, vomiting, photophobia, and altered mental status strongly suggest meningitis.

Q2

What is the most appropriate management?

AOral hydration and reassessment in 48 hoursBEmergency hospital transfer and prompt empiric antimicrobial treatmentCHomeopathic treatment followed by observationDMassage therapy for neck stiffnessERoutine outpatient neurology referral

Reveal answer and rationale

✓Correct answer: B. Emergency hospital transfer and prompt empiric antimicrobial treatment

Suspected bacterial meningitis is a medical emergency. Treatment should not be delayed unnecessarily.

Q3

Which finding may require neuroimaging before lumbar puncture?

Reveal answer and rationale

✓Correct answer: B. New focal neurologic deficit

Features suggesting increased intracranial pressure or a mass lesion may require brain imaging before lumbar puncture. Antimicrobial treatment should not be unnecessarily delayed.

Q4

Which naturopathic intervention is contraindicated during the acute presentation?

AEmergency referralBMonitoring vital signsCCervical manipulation for neck stiffnessDProviding the emergency team with medication historyEInfection-control precautions

Reveal answer and rationale

✓Correct answer: C. Cervical manipulation for neck stiffness

Neck stiffness in suspected meningitis is not a mechanical musculoskeletal complaint and should not be treated with manipulation.

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Diagnosis: Acute bacterial meningitis

Key differentials

Viral meningitis
Encephalitis
Subarachnoid hemorrhage
Brain abscess
Severe migraine
Intracranial mass lesion

Key investigations

Blood cultures
CBC
Glucose
Electrolytes
Renal and hepatic function
Lumbar puncture with cerebrospinal-fluid analysis when safe
Neuroimaging when indicated

Treatment principles

Emergency transfer
Prompt empiric intravenous antimicrobials
Organism-specific treatment when identified
Appropriate adjunctive treatment
Infection-control and public-health measures when relevant

Botanical medicine: No botanical antimicrobial should replace urgent intravenous treatment.

Physical medicine: Cervical manipulation is contraindicated.

Clinical Pearl: The complete classic triad may not be present in every patient.

NPLEX Trap: Do not delay emergency antimicrobial treatment solely to complete every diagnostic procedure.

Reference basis: Current meningitis guidance emphasizes rapid recognition, urgent hospital care, and timely intravenous antimicrobial therapy.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 10

Severe Hyperkalemia in Chronic Kidney DiseaseClinical Case 10

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 71-year-old man with chronic kidney disease and heart failure presents with weakness and palpitations. Medications:

Ramipril
Spironolactone
Furosemide
Potassium supplement He recently began using a potassium-based salt substitute. Laboratory results:
Potassium: 7.1 mmol/L
Creatinine: 290 µmol/L

Bicarbonate: 17 mmol/L ECG demonstrates tall peaked T waves and widening of the QRS complex.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Severe hyperkalemia with ECG toxicity

A potassium level of 7.1 mmol/L with peaked T waves and QRS widening indicates life-threatening hyperkalemia.

Q2

Which treatment is used immediately to stabilize the cardiac membrane?

Reveal answer and rationale

✓Correct answer: A. Intravenous calcium

Intravenous calcium is used when significant ECG manifestations are present because it helps stabilize the myocardium. It does not remove potassium from the body.

Q3

Which treatment temporarily shifts potassium into cells?

Reveal answer and rationale

✓Correct answer: A. Insulin with glucose

Insulin promotes intracellular potassium movement. Glucose is given when appropriate to reduce the risk of treatment-related hypoglycemia.

Q4

Which combination most likely contributed to the hyperkalemia?

ARamipril, spironolactone, potassium supplement, and potassium salt substituteBFurosemide and a low-potassium dietCAcetaminophen and vitamin DDInhaled salbutamol and insulinECalcium carbonate and iron

Reveal answer and rationale

✓Correct answer: A. Ramipril, spironolactone, potassium supplement, and potassium salt substitute

Renin-angiotensin-system inhibition, mineralocorticoid-receptor antagonism, potassium supplementation, reduced renal function, and potassium-containing salt substitutes may combine to increase serum potassium.

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Disease Review & Exam Traps

Diagnosis: Severe hyperkalemia with cardiac electrical toxicity

Potential causes

Chronic kidney disease
Acute kidney injury
ACE inhibitors
ARBs
Mineralocorticoid-receptor antagonists
Potassium supplements
Potassium-based salt substitutes
Metabolic acidosis
Tissue breakdown

Key investigations

Repeat potassium when appropriate without delaying treatment
Immediate ECG
Renal function
Glucose
Bicarbonate
Magnesium
Medication and supplement review

Treatment principles

Stabilize the myocardium when ECG toxicity is present.
Shift potassium into cells.
Remove potassium from the body.
Treat the underlying cause.
Monitor ECG, glucose, and electrolytes.

Nutrition: Dietary potassium advice should be individualized. Hidden potassium sources, especially salt substitutes, should be reviewed.

Botanical medicine: Review all products for potassium content and renal safety.

Pharmacology safety: Do not automatically discontinue beneficial long-term medications permanently; first address the acute emergency and then reassess the regimen, contributing factors, and monitoring strategy.

Clinical Pearl: ECG changes make hyperkalemia an immediate cardiac emergency.

NPLEX Trap: Intravenous calcium protects the heart but does not lower total-body potassium.

Reference basis: Kidney guidance emphasizes immediate ECG assessment, cardiac stabilization when indicated, intracellular potassium shifting, potassium removal, and review of contributing medications and dietary sources.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 11

Acute Pulmonary EmbolismClinical Case 11

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 48-year-old woman presents with sudden shortness of breath and sharp right-sided chest pain that worsens with inspiration. She returned three days ago from a 12-hour international flight. She takes a combined estrogen-containing oral contraceptive and reports new swelling and tenderness of her left calf. Vital signs:

BP: 106/68 mmHg
HR: 118/min
RR: 28/min
Temperature: 37.2°C
SpO₂: 89% on room air Physical examination:
Appears anxious and dyspneic
Lungs are clear to auscultation

Left calf is swollen and tender
No chest-wall tenderness

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute pulmonary embolism

The combination of sudden dyspnea, pleuritic chest pain, hypoxemia, tachycardia, prolonged immobility, estrogen use, and unilateral calf swelling strongly suggests pulmonary embolism originating from a deep-vein thrombosis. Why the Other Options Are Incorrect

A. Pneumonia: More commonly causes fever, cough, and focal lung findings.
C. Costochondritis: Produces reproducible chest-wall tenderness but not hypoxemia or unilateral leg swelling.
D. Panic disorder: Does not adequately explain objective hypoxemia and signs of DVT.
E. Bronchitis: Usually presents with cough and does not cause unilateral calf swelling.

Q2

What is the most appropriate next step?

AReassure the patient and prescribe breathing exercisesBArrange emergency assessment and definitive pulmonary vascular imagingCOrder an outpatient chest radiograph for next weekDBegin oral antibioticsERecommend horse-chestnut extract and compression stockings only

Reveal answer and rationale

✓Correct answer: B. Arrange emergency assessment and definitive pulmonary vascular imaging

This patient has a high clinical probability of pulmonary embolism with hypoxemia and tachycardia. She requires urgent hospital evaluation, risk classification, imaging, and treatment. NPLEX Trap A normal lung examination does not exclude pulmonary embolism.

Q3

Which diagnostic study is generally preferred to confirm pulmonary embolism in a hemodynamically stable patient without a major contraindication to contrast?

Reveal answer and rationale

✓Correct answer: A. CT pulmonary angiography

CT pulmonary angiography directly evaluates the pulmonary arterial circulation and is commonly used as the definitive imaging study in stable patients. A ventilation-perfusion scan may be appropriate when CT contrast is contraindicated or radiation considerations make it preferable.

Q4

Which treatment is generally required after acute pulmonary embolism is confirmed, assuming there is no contraindication?

Reveal answer and rationale

✓Correct answer: A. Anticoagulation

Anticoagulation prevents thrombus extension and recurrent venous thromboembolism. The exact medication and treatment setting depend on severity, bleeding risk, renal function, pregnancy status, drug interactions, and other patient factors. The 2026 AHA/ACC multisociety guideline recommends structured PE severity classification. Direct oral anticoagulants are generally preferred over vitamin K antagonists in eligible patients, while low-molecular-weight heparin is preferred when initial parenteral anticoagulation is required.

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Diagnosis: Acute pulmonary embolism, likely arising from left-leg DVT

Major risk factors

Recent surgery or hospitalization
Prolonged immobility or long-distance travel
Active malignancy
Estrogen therapy
Pregnancy and postpartum state
Previous venous thromboembolism
Inherited or acquired thrombophilia

Key differentials

Acute coronary syndrome
Pneumonia
Pneumothorax
Aortic dissection
Pericarditis
Panic attack

Musculoskeletal pain

Key investigations

Clinical probability assessment
ECG
Oxygen saturation
CBC and renal function
Pregnancy testing when applicable
D-dimer in appropriately selected low- or intermediate-probability patients
CT pulmonary angiography
Ventilation-perfusion scan when appropriate
Leg venous ultrasound
Cardiac biomarkers and echocardiography for severity assessment

Treatment principles

Emergency assessment
Oxygen when clinically indicated
Anticoagulation when appropriate
Hemodynamic support
Advanced reperfusion treatment for selected patients with severe PE
Evaluation of bleeding risk and provoking factors

Botanical safety: Ginkgo, garlic extracts, high-dose fish oil, and other supplements with potential antiplatelet effects should be documented when anticoagulants are prescribed.

Clinical Pearl: Clear breath sounds do not rule out a life-threatening pulmonary embolism.

NPLEX Trap: Do not use D-dimer as a stand-alone rule-out test in a patient with a high clinical probability of PE.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 12

Acute Gallstone PancreatitisClinical Case 12

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 45-year-old woman presents with severe, constant epigastric pain radiating to her back. The pain began after a large fatty meal and is accompanied by nausea and repeated vomiting.

Medical history:

Obesity
Known gallstones Vital signs:
BP: 108/70 mmHg
HR: 108/min
RR: 22/min
Temperature: 38.0°C Physical examination:
Epigastric tenderness
Reduced bowel sounds
No rebound tenderness Laboratory findings:
Lipase: 1,450 U/L
ALT: 225 U/L
Total bilirubin: mildly elevated
WBC: 15.2 × 10⁹/L

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Acute gallstone pancreatitis

Typical severe epigastric pain radiating to the back, vomiting, and markedly elevated lipase support acute pancreatitis. The history of gallstones and abnormal liver tests suggest a biliary cause.

Q2

Which combination is generally sufficient to diagnose acute pancreatitis?

AAny abdominal pain plus feverBTwo of three: characteristic pain, pancreatic enzymes significantly elevated, or characteristic imagingCElevated amylase aloneDGallstones plus nauseaELeukocytosis plus vomiting

Reveal answer and rationale

✓Correct answer: B. Two of three: characteristic pain, pancreatic enzymes significantly elevated, or characteristic imaging

Acute pancreatitis is generally diagnosed when at least two of the following are present:

Characteristic abdominal pain
Serum lipase or amylase markedly elevated
Characteristic imaging findings

Q3

What is an appropriate early management approach?

ARoutine prolonged fasting for all patientsBSupportive care with appropriate fluids, analgesia, monitoring, and early oral or enteral nutrition as toleratedCImmediate pancreatic-enzyme supplementation onlyDRoutine prophylactic antibiotics in every caseEHigh-fat feeding during active vomiting

Reveal answer and rationale

✓Correct answer: B. Supportive care with appropriate fluids, analgesia, monitoring, and early oral or enteral nutrition as tolerated

Treatment is primarily supportive. Fluid administration should be individualized, pain and nausea controlled, complications monitored, and nutrition resumed early when clinically tolerated rather than continuing unnecessary prolonged fasting.

Q4

Which circumstance most strongly supports urgent ERCP?

AMild pancreatitis that is rapidly improvingBGallstone pancreatitis complicated by acute cholangitis or persistent biliary obstructionCElevated lipase without biliary diseaseDPancreatitis caused by hypertriglyceridemiaEChronic constipation

Reveal answer and rationale

✓Correct answer: B. Gallstone pancreatitis complicated by acute cholangitis or persistent biliary obstruction

Urgent biliary intervention may be necessary when gallstone pancreatitis is accompanied by cholangitis or ongoing common-bile-duct obstruction. ERCP is not routinely required for every patient with gallstone pancreatitis. The 2025 international acute-pancreatitis guideline addresses fluid therapy, nutrition, biliary interventions, complications, and etiologic management. The ACG guideline similarly supports early refeeding and reserves urgent ERCP for selected biliary complications.

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Diagnosis: Acute gallstone pancreatitis

Common causes

Gallstones
Alcohol
Hypertriglyceridemia
Medications
Hypercalcemia
Trauma
Post-ERCP pancreatitis

Key investigations

Lipase
CBC
Electrolytes
Renal function
Glucose
Calcium
Liver enzymes and bilirubin
Triglycerides
Abdominal ultrasound
CT when diagnosis is uncertain or complications are suspected

Potential complications

Hypovolemia
Acute kidney injury
Respiratory failure
Pancreatic necrosis
Infection
Pseudocyst
Systemic inflammatory response
Multiorgan dysfunction

Treatment principles

Hospital assessment
Individualized fluid resuscitation
Adequate analgesia
Antiemetic treatment
Early nutrition as tolerated
Treatment of the cause
Cholecystectomy planning after appropriate stabilization in biliary disease

Botanical safety: Choleretic or cholagogue herbs are not appropriate substitutes for emergency evaluation in acute gallstone pancreatitis and may worsen symptoms when biliary obstruction is present.

Clinical Pearl: Lipase is generally more useful than amylase because it remains elevated longer.

NPLEX Trap: Do not prescribe routine prophylactic antibiotics for uncomplicated sterile acute pancreatitis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 13

Hypertensive EmergencyClinical Case 13

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 61-year-old man presents with severe headache, blurred vision, confusion, and shortness of breath. He stopped taking his antihypertensive medications two weeks ago. Vital signs:

BP: 232/138 mmHg
HR: 102/min
RR: 26/min
SpO₂: 91% on room air Physical examination:
Confused
Bilateral lung crackles
Papilledema
No focal motor deficit Laboratory findings:
Creatinine: elevated
Urinalysis: proteinuria and microscopic hematuria

Q1

What is the most likely diagnosis?

AWhite-coat hypertensionBHypertensive emergencyCChronic uncomplicated hypertensionDPanic attackEMigraine without complication

Reveal answer and rationale

✓Correct answer: B. Hypertensive emergency

Severely elevated blood pressure accompanied by acute neurologic, cardiac, retinal, pulmonary, and renal injury indicates hypertensive emergency. Blood pressure level alone does not establish the diagnosis; acute target-organ damage is the defining feature.

Q2

Which finding most clearly distinguishes hypertensive emergency from severe asymptomatic hypertension?

ASystolic blood pressure above 180 mmHgBAcute target-organ injuryCHistory of hypertensionDMild anxietyEMedication nonadherence

Reveal answer and rationale

✓Correct answer: B. Acute target-organ injury

Severe hypertension without acute organ injury is managed differently from hypertension causing encephalopathy, pulmonary edema, acute kidney injury, retinal damage, myocardial ischemia, or aortic injury.

Q3

What is the most appropriate management?

ARapidly normalize blood pressure at home with several oral medicationsBHospitalize for continuous monitoring and controlled intravenous blood-pressure reductionCRecommend meditation and reassess in one weekDAdminister a botanical diuretic onlyEDelay treatment until ambulatory blood-pressure monitoring is completed

Reveal answer and rationale

✓Correct answer: B. Hospitalize for continuous monitoring and controlled intravenous blood-pressure reduction

Hypertensive emergency requires monitored treatment with titratable intravenous medication. Excessive or abrupt lowering can compromise cerebral, coronary, and renal perfusion.

Q4

For many hypertensive emergencies, what is the usual initial blood-pressure reduction principle?

AReduce mean arterial pressure to normal within five minutesBReduce mean arterial pressure cautiously, often by approximately 20–25% during the initial hourCDo not lower blood pressure for 48 hoursDReduce systolic pressure below 100 mmHg immediatelyEUse only sublingual rapid-acting medication

Reveal answer and rationale

✓Correct answer: B. Reduce mean arterial pressure cautiously, often by approximately 20–25% during the initial hour

A controlled initial reduction limits ongoing organ injury while avoiding ischemia from excessive lowering. Exact goals differ in aortic dissection, ischemic stroke, intracranial hemorrhage, pregnancy-related emergencies, and other special situations.

Contemporary hypertension guidance distinguishes severe blood-pressure elevation from true emergency based on acute end-organ damage and supports monitored, controlled reduction rather than abrupt normalization.

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Diagnosis: Hypertensive emergency with encephalopathy, pulmonary edema, retinal injury, and renal involvement

Possible manifestations

Hypertensive encephalopathy
Acute coronary syndrome
Acute pulmonary edema
Acute kidney injury
Aortic dissection
Intracranial hemorrhage
Ischemic stroke
Retinopathy
Eclampsia

Key investigations

Repeat accurate blood-pressure measurement
Neurologic and retinal examination
ECG
Cardiac biomarkers
CBC
Electrolytes and renal function
Urinalysis
Chest imaging
Brain imaging when neurologic symptoms are present
Evaluation for secondary causes when appropriate

Treatment principles

Emergency hospitalization
Continuous blood-pressure and cardiac monitoring
Intravenous antihypertensive therapy
Treatment tailored to the injured organ
Avoid excessive or abrupt reduction

Botanical safety: Licorice can increase blood pressure through mineralocorticoid-like effects and should be specifically reviewed.

Clinical Pearl: The presence of papilledema, confusion, pulmonary edema, or acute kidney injury changes severe hypertension into an emergency.

NPLEX Trap: Do not attempt immediate normalization of blood pressure in most hypertensive emergencies.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 14

Thyroid StormClinical Case 14

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 34-year-old woman with untreated Graves disease presents with fever, agitation, vomiting, diarrhea, and palpitations after developing pneumonia. Vital signs:

BP: 146/72 mmHg
HR: 164/min and irregular
RR: 28/min
Temperature: 40.1°C Physical examination:
Agitated and confused
Diffuse goiter
Fine tremor
Warm, moist skin
Bibasilar crackles ECG demonstrates atrial fibrillation with a rapid ventricular response. Laboratory findings:
TSH: suppressed
Free T4: elevated
Liver enzymes: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Thyroid storm

Severe thyrotoxicosis with high fever, marked tachycardia, atrial fibrillation, gastrointestinal symptoms, heart failure, agitation, and delirium indicates thyroid storm. Thyroid storm is a clinical diagnosis; hormone levels do not necessarily distinguish it from uncomplicated hyperthyroidism.

Q2

Which treatment sequence is most appropriate?

AIodine first, followed by antithyroid medication several hours laterBBeta-blockade when appropriate, antithyroid medication, iodine after antithyroid therapy, corticosteroid, and supportive treatmentCLevothyroxine followed by iodineDAspirin alone for feverERadioactive iodine as immediate emergency therapy

Reveal answer and rationale

✓Correct answer: B. Beta-blockade when appropriate, antithyroid medication, iodine after antithyroid therapy, corticosteroid, and supportive treatment

Management blocks adrenergic activity, inhibits new hormone synthesis, limits hormone release, reduces peripheral T4-to-T3 conversion, and treats the precipitating cause.

Iodine should be administered only after antithyroid medication so that iodine does not provide substrate for additional thyroid-hormone synthesis.

Q3

Which antipyretic should generally be avoided because it may increase free thyroid-hormone levels?

Reveal answer and rationale

✓Correct answer: B. Aspirin

Salicylates can displace thyroid hormones from binding proteins and may increase the free hormone fraction. Acetaminophen and physical cooling measures are generally preferred for fever control.

Q4

Which botanical medicine is inappropriate because it may provide substantial iodine and potentially aggravate thyrotoxicosis?

Reveal answer and rationale

✓Correct answer: A. Fucus vesiculosus

Bladderwrack can contain substantial and variable amounts of iodine and is inappropriate in uncontrolled hyperthyroidism or thyroid storm. Thyroid storm requires intensive-care treatment. Current expert management includes supportive care, beta-adrenergic control when tolerated, thionamide therapy, iodine after thionamide administration, corticosteroids, and treatment of the precipitating event.

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Diagnosis: Thyroid storm precipitated by pneumonia

Common precipitants

Infection
Surgery
Trauma
Childbirth
Stopping antithyroid medication
Iodinated contrast exposure
Diabetic ketoacidosis
Myocardial infarction

Key investigations

TSH
Free T4 and T3
ECG
CBC
Electrolytes
Glucose
Liver and renal function
Cardiac biomarkers when indicated
Investigation for infection or another precipitating cause

Treatment principles

Support airway, breathing, and circulation.
Control excessive adrenergic activity.
Block thyroid-hormone synthesis.
Block thyroid-hormone release after synthesis inhibition.
Reduce peripheral T4-to-T3 conversion.
Treat the precipitating cause.

Homeopathy and botanical medicine: Neither is appropriate as primary treatment in thyroid storm.

Clinical Pearl: Thyroid storm severity is determined clinically, not by how high the free T4 level is.

NPLEX Trap: Administer antithyroid medication before iodine.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 15

Acute AppendicitisClinical Case 15

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 19-year-old man presents with 18 hours of abdominal pain. The pain began near the umbilicus and has migrated to the right lower quadrant. He reports anorexia, nausea, and one episode of vomiting. Vital signs:

BP: 118/72 mmHg
HR: 102/min
Temperature: 38.1°C Physical examination:
Right lower-quadrant tenderness
Guarding at McBurney point
Positive Rovsing sign
Increased pain with coughing Laboratory findings:
WBC: 14.6 × 10⁹/L
Neutrophilia

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Acute appendicitis

The classic migration of pain from the periumbilical area to the right lower quadrant, anorexia, nausea, fever, neutrophilia, and localized peritoneal irritation strongly suggest acute appendicitis.

Q2

What is the most appropriate next step?

ABegin a high-fibre diet and reassess in one weekBArrange urgent emergency or surgical evaluationCPerform deep abdominal massageDAdminister a stimulant laxativeERecommend a castor-oil pack and discharge

Reveal answer and rationale

✓Correct answer: B. Arrange urgent emergency or surgical evaluation

Suspected appendicitis requires urgent evaluation because delayed treatment can lead to perforation, abscess, peritonitis, and sepsis.

Q3

Which imaging study is commonly used in a nonpregnant adult when imaging is required?

Reveal answer and rationale

✓Correct answer: A. CT of the abdomen and pelvis

CT has high diagnostic accuracy in adults. Ultrasound is commonly preferred as the first study in children and pregnancy to reduce radiation exposure.

Q4

Which intervention should be avoided?

AKeeping the patient fasting while awaiting surgical assessmentBIntravenous fluids when indicatedCRepeated deep palpation, laxatives, or vigorous abdominal manipulationDAppropriate analgesiaESurgical consultation

Reveal answer and rationale

✓Correct answer: C. Repeated deep palpation, laxatives, or vigorous abdominal manipulation

These interventions may worsen pain, delay appropriate care, or increase risk when an inflamed or perforated appendix is present.

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Diagnosis: Acute appendicitis

Key differentials

Gastroenteritis
Mesenteric adenitis
Crohn disease
Renal colic
Pyelonephritis
Ectopic pregnancy
Ovarian torsion
Pelvic inflammatory disease

Key investigations

CBC
Electrolytes
Urinalysis
Pregnancy test when applicable
Ultrasound in appropriate populations
CT in many nonpregnant adults

Treatment principles

Urgent surgical assessment
Fasting
Fluids and analgesia when indicated
Antibiotics
Appendectomy in most appropriate cases
Selected nonoperative management in carefully chosen uncomplicated cases under medical supervision

Physical medicine: Abdominal manipulation is contraindicated when an acute surgical abdomen is suspected.

Clinical Pearl: Early appendicitis may begin with vague central abdominal discomfort before localizing.

NPLEX Trap: Analgesia should not be withheld solely because it might “mask” the diagnosis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 16

Acute Adrenal CrisisClinical Case 16

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 44-year-old woman with primary adrenal insufficiency presents with vomiting, severe weakness, abdominal pain, and dizziness. She developed gastroenteritis two days ago and has been unable to keep her hydrocortisone tablets down. Vital signs:

BP: 76/44 mmHg
HR: 126/min
RR: 24/min
Temperature: 38.2°C Laboratory findings:
Sodium: 123 mmol/L
Potassium: 6.0 mmol/L
Glucose: 2.8 mmol/L
Creatinine: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute adrenal crisis

Known adrenal insufficiency, inability to take glucocorticoids, severe hypotension, vomiting, abdominal pain, hyponatremia, hyperkalemia, and hypoglycemia strongly indicate adrenal crisis.

Q2

What is the most appropriate immediate treatment?

AOral hydrocortisone and home observationBImmediate parenteral hydrocortisone and intravenous isotonic fluid resuscitationCInsulin aloneDFluid restrictionESpironolactone

Reveal answer and rationale

✓Correct answer: B. Immediate parenteral hydrocortisone and intravenous isotonic fluid resuscitation

Treatment should not be delayed for confirmatory testing when adrenal crisis is strongly suspected. Hypoglycemia must also be corrected, and the precipitating illness treated.

Q3

Why is hyperkalemia characteristic of primary adrenal insufficiency?

AExcess aldosterone increases potassium retentionBAldosterone deficiency reduces renal potassium excretionCExcess insulin moves potassium out of cellsDIncreased cortisol causes renal failureEExcess thyroid hormone prevents potassium excretion

Reveal answer and rationale

✓Correct answer: B. Aldosterone deficiency reduces renal potassium excretion

Primary adrenal failure reduces both cortisol and aldosterone. Reduced aldosterone causes sodium loss, volume depletion, and potassium retention. Hyperkalemia is less characteristic of secondary adrenal insufficiency because aldosterone production is usually preserved.

Q4

Which sick-day instruction is most appropriate?

AStop glucocorticoids during infectionBFollow a prescribed stress-dosing plan and use emergency injectable glucocorticoid if oral medication cannot be retainedCReplace glucocorticoids with licoriceDRestrict all fluids during vomitingEDouble potassium intake during illness

Reveal answer and rationale

✓Correct answer: B. Follow a prescribed stress-dosing plan and use emergency injectable glucocorticoid if oral medication cannot be retained

Patients need clear sick-day rules, emergency identification, injectable medication training, and instructions to obtain urgent care when vomiting prevents oral dosing.

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Diagnosis: Acute adrenal crisis caused by interrupted glucocorticoid absorption during gastroenteritis

Common triggers

Infection
Vomiting or diarrhea
Surgery
Trauma
Abrupt glucocorticoid withdrawal
Failure to increase glucocorticoid dosage during physiologic stress

Key investigations

Electrolytes
Glucose
Renal function
Cortisol and ACTH when feasible before treatment
CBC
Cultures and infection assessment
ECG when hyperkalemia is present

Treatment principles

Immediate parenteral hydrocortisone
Isotonic intravenous fluids
Glucose when hypoglycemia is present
Electrolyte monitoring
Treatment of the precipitating cause

Botanical safety: Licorice is not a replacement for glucocorticoid or mineralocorticoid therapy and may create significant blood-pressure and electrolyte complications.

Clinical Pearl: Do not delay lifesaving corticosteroid treatment while waiting for cortisol results.

NPLEX Trap: Hyperkalemia supports primary rather than secondary adrenal insufficiency.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 17

Myasthenic CrisisClinical Case 17

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 56-year-old woman with myasthenia gravis presents with increasing difficulty swallowing, weak speech, and shortness of breath after developing a respiratory infection. Medications:

Pyridostigmine
Prednisone
Azithromycin started yesterday at a walk-in clinic Vital signs:
BP: 130/76 mmHg
HR: 108/min
RR: 30/min
SpO₂: 92% Physical examination:
Bilateral ptosis
Nasal, weak voice
Difficulty holding her head upright
Weak cough
Reduced breath sounds at the bases

Forced vital capacity is markedly reduced.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Myasthenic crisis

Worsening bulbar weakness, weak cough, respiratory-muscle weakness, and reduced forced vital capacity in a patient with myasthenia gravis indicate impending or established myasthenic crisis.

Q2

What is the immediate management priority?

AIncrease exercise intensityBProtect ventilation and arrange intensive-care managementCGive oral magnesiumDPerform cervical manipulationEDischarge with reassurance

Reveal answer and rationale

✓Correct answer: B. Protect ventilation and arrange intensive-care management

Respiratory failure may develop rapidly. Serial respiratory measurements, airway protection, ventilatory support, and treatment of the trigger are priorities.

Q3

Which treatments are commonly used to produce relatively rapid improvement in severe myasthenic crisis?

AIntravenous immunoglobulin or plasma exchangeBOral iron and vitamin B12CAntihistaminesDAcetaminophen aloneEInhaled corticosteroid alone

Reveal answer and rationale

✓Correct answer: A. Intravenous immunoglobulin or plasma exchange

IV immunoglobulin and plasma exchange can improve neuromuscular transmission during severe exacerbation while the underlying trigger and longer-term immunotherapy are addressed.

Q4

Which supplement should generally be avoided because it can worsen neuromuscular transmission?

Reveal answer and rationale

✓Correct answer: A. Magnesium

Magnesium can impair acetylcholine release at the neuromuscular junction and may worsen weakness in myasthenia gravis.

Some antibiotics, including macrolides, fluoroquinolones, and aminoglycosides, may also worsen myasthenic symptoms and should be reviewed carefully.

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Diagnosis: Myasthenic crisis precipitated by respiratory infection and potentially aggravated by medication

Common triggers

Infection
Surgery
Pregnancy or postpartum changes
Medication effects
Reduction of immunotherapy
Aspiration
Emotional or physiologic stress

Key assessments

Airway and swallowing
Strength of cough
Respiratory rate
Forced vital capacity
Negative inspiratory force
Oxygenation and ventilation
Infection evaluation

Treatment principles

Intensive respiratory monitoring
Early airway and ventilatory support when needed
IV immunoglobulin or plasma exchange
Treatment of infection or another precipitating factor
Review of aggravating medications

Contraindicated or concerning agents

Magnesium
Aminoglycosides
Fluoroquinolones
Macrolides
Certain beta-blockers

Neuromuscular-blocking agents

Clinical Pearl: Oxygen saturation can remain relatively normal until late because the primary problem is hypoventilation rather than initial oxygen-transfer failure.

NPLEX Trap: Do not rely only on pulse oximetry when respiratory-muscle weakness is suspected.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 18

Acute Angle-Closure GlaucomaClinical Case 18

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 63-year-old woman presents with sudden severe right-eye pain, headache, blurred vision, nausea, and vomiting. She reports seeing halos around lights. Symptoms began after she entered a dark movie theatre. Physical examination:

Right eye is red
Cornea appears cloudy
Pupil is mid-dilated and poorly reactive
The globe feels firm
Visual acuity is reduced

Q1

What is the most likely diagnosis?

AViral conjunctivitisBAcute angle-closure glaucomaCOpen-angle glaucomaDSubconjunctival hemorrhageEAllergic conjunctivitis

Reveal answer and rationale

✓Correct answer: B. Acute angle-closure glaucoma

Sudden painful red eye, reduced vision, halos, headache, vomiting, corneal clouding, and a fixed or poorly reactive mid-dilated pupil are classic for acute angle closure.

Q2

What is the most appropriate action?

ARoutine optometry appointment in one monthBImmediate emergency ophthalmologic treatmentCArtificial tears and home observationDOral antihistamine and dischargeEEye massage

Reveal answer and rationale

✓Correct answer: B. Immediate emergency ophthalmologic treatment

Rapidly elevated intraocular pressure can cause permanent optic-nerve damage and vision loss. Pressure-lowering treatment and definitive ophthalmologic care must begin urgently.

Q3

Which medication class can precipitate angle closure in a susceptible patient through pupillary dilation?

Reveal answer and rationale

✓Correct answer: A. Anticholinergic medication

Anticholinergic and sympathomimetic medications may dilate the pupil and precipitate angle closure in anatomically susceptible eyes.

Q4

Which clinical feature is more consistent with acute angle closure than uncomplicated conjunctivitis?

AMild itchingBBilateral watery dischargeCSevere pain with reduced vision and vomitingDCrusting of the eyelashesERecent contact with a person who has a red eye

Reveal answer and rationale

✓Correct answer: C. Severe pain with reduced vision and vomiting

Conjunctivitis usually causes irritation, discharge, and redness but not a firm globe, severe systemic symptoms, corneal haze, or major visual loss.

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Diagnosis: Acute angle-closure glaucoma

Key differentials

Anterior uveitis
Keratitis
Scleritis
Conjunctivitis
Orbital cellulitis
Migraine
Cluster headache

Key assessments

Visual acuity
Pupil examination
Slit-lamp examination
Intraocular pressure
Anterior-chamber assessment
Optic-nerve evaluation

Treatment principles

Immediate pressure reduction
Urgent ophthalmology consultation
Definitive laser peripheral iridotomy when appropriate
Assessment of the opposite eye

Medication review

Anticholinergics
Sympathomimetic decongestants
Certain antidepressants
Topiramate
Other medications associated with angle changes or mydriasis

Clinical Pearl: A painful red eye with decreased vision is an emergency until proven otherwise.

NPLEX Trap: Open-angle glaucoma is usually chronic and initially painless; the dramatic acute presentation indicates angle closure.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 19

Acute Septic ArthritisClinical Case 19

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 68-year-old man presents with sudden severe pain and swelling of his right knee. He cannot bear weight. Medical history:

Type 2 diabetes
Rheumatoid arthritis
Chronic prednisone use Vital signs:

BP: 116/70 mmHg
HR: 112/min
Temperature: 39.0°C Physical examination:
Large, warm knee effusion
Severe pain with passive movement
Overlying erythema
Markedly restricted range of motion

Q1

What is the most likely diagnosis?

AOsteoarthritisBSeptic arthritisCChronic rheumatoid arthritis flare onlyDPatellofemoral pain syndromeEIliotibial-band syndrome

Reveal answer and rationale

✓Correct answer: B. Septic arthritis

An acutely painful, hot, swollen monoarthritis with fever and inability to bear weight must be considered septic arthritis until proven otherwise, particularly in an immunosuppressed patient.

Q2

What is the most important diagnostic procedure?

ASerum uric acid aloneBUrgent arthrocentesis with synovial-fluid analysis and cultureCRoutine knee radiograph onlyDRheumatoid factorEBone-density testing

Reveal answer and rationale

✓Correct answer: B. Urgent arthrocentesis with synovial-fluid analysis and culture

Synovial fluid should be assessed for:

Cell count and differential
Gram stain
Culture and sensitivities
Crystal analysis Blood cultures should also be obtained when systemic infection is suspected.

Q3

Which finding excludes septic arthritis?

AIdentification of monosodium urate crystalsBNormal serum uric acidCNeither finding reliably excludes septic arthritisDPre-existing osteoarthritisEA negative rheumatoid factor

Reveal answer and rationale

✓Correct answer: C. Neither finding reliably excludes septic arthritis

Crystal arthritis and infection can coexist. Finding urate or calcium-pyrophosphate crystals does not eliminate the need to assess for infection.

Q4

What is the appropriate treatment approach?

AJoint manipulation and exerciseBPrompt intravenous antibiotics and joint drainage after appropriate culturesCOral glucosamine onlyDIntra-articular corticosteroid before infection is excludedEHeat therapy and observation

Reveal answer and rationale

✓Correct answer: B. Prompt intravenous antibiotics and joint drainage after appropriate cultures

Septic arthritis can rapidly destroy cartilage and cause bacteremia or sepsis. Treatment generally requires antimicrobial therapy and drainage.

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Diagnosis: Acute septic arthritis of the knee

Risk factors

Advanced age
Diabetes
Immunosuppression
Rheumatoid arthritis
Prosthetic joint
Recent surgery or injection
Skin infection
Injection-drug use

Key differentials

Gout
Pseudogout
Rheumatoid arthritis flare
Hemarthrosis
Reactive arthritis
Traumatic injury

Key investigations

Arthrocentesis
Synovial-fluid culture
Crystal analysis
CBC

Inflammatory markers
Blood cultures
Ultrasound to identify an effusion
Imaging for complications when indicated

Treatment principles

Obtain cultures without unnecessary delay
Prompt antimicrobial therapy
Joint drainage
Orthopedic or surgical consultation
Treatment of bacteremia or an infectious source

Physical medicine: Manipulation, exercise, heat, and intra-articular injection are inappropriate before infection has been excluded.

Clinical Pearl: Crystal identification does not rule out simultaneous septic arthritis.

NPLEX Trap: Do not diagnose gout solely from an elevated serum uric-acid level.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 20

Carbon Monoxide PoisoningClinical Case 20

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 39-year-old man, his spouse, and their child develop headache, dizziness, nausea, and fatigue during the winter. Their symptoms improve after leaving the house. The furnace was recently repaired, and a carbon-monoxide detector is not installed. The patient presents with:

Headache
Confusion
Chest discomfort
Unsteady gait Vital signs:
BP: 138/82 mmHg

HR: 110/min
RR: 22/min
SpO₂: 99% on a standard pulse oximeter

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Carbon monoxide poisoning

Several household members developing nonspecific neurologic and gastrointestinal symptoms that improve away from the home strongly suggests environmental carbon-monoxide exposure.

Q2

Why does the normal pulse-oximeter reading not exclude carbon monoxide poisoning?

ACarbon monoxide causes only venous hypoxemiaBStandard pulse oximetry cannot reliably distinguish oxyhemoglobin from carboxyhemoglobinCCarbon monoxide does not affect oxygen transportDPulse oximetry measures only carbon dioxideEThe reading is normal because exposure has no clinical importance

Reveal answer and rationale

✓Correct answer: B. Standard pulse oximetry cannot reliably distinguish oxyhemoglobin from carboxyhemoglobin

Standard pulse oximeters may display a falsely reassuring oxygen saturation because they cannot accurately differentiate oxyhemoglobin from carboxyhemoglobin.

Q3

What is the most appropriate immediate treatment?

Reveal answer and rationale

✓Correct answer: A. High-concentration oxygen and emergency evaluation

The patient should be removed from exposure and given high-concentration oxygen. Neurologic symptoms, cardiac symptoms, pregnancy, severe acidosis, loss of consciousness, and elevated carboxyhemoglobin may influence consideration of hyperbaric oxygen treatment.

Q4

Which diagnostic test is most useful?

Reveal answer and rationale

✓Correct answer: A. Carboxyhemoglobin level measured by co-oximetry

Co-oximetry directly measures carboxyhemoglobin. A lower level after oxygen treatment or delayed testing does not necessarily reflect the peak exposure, so clinical history remains essential.

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Diagnosis: Carbon monoxide poisoning from a probable defective furnace

Common exposure sources

Furnaces
Fireplaces
Generators
Motor vehicles in enclosed spaces
Gas-powered equipment
House fires

Common manifestations

Headache
Dizziness
Nausea
Fatigue
Confusion
Ataxia
Syncope
Seizures
Chest pain
Myocardial injury

Key investigations

Carboxyhemoglobin by co-oximetry
ECG
Cardiac biomarkers
Blood gas and lactate when indicated
Pregnancy testing when relevant
Neurologic examination

Treatment principles

Remove the patient from exposure
Administer high-concentration oxygen

Emergency assessment
Consider hyperbaric oxygen in selected severe cases
Notify appropriate emergency and environmental services
Do not allow occupants to return until the source is professionally assessed

Clinical Pearl: Carbon monoxide poisoning can produce normal standard pulse-oximeter readings.

NPLEX Trap: Do not exclude carbon monoxide exposure because the patient’s skin is not “cherry red”; that finding is uncommon and unreliable.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 21

Acute Stanford Type A Aortic DissectionClinical Case 21

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 66-year-old man with long-standing hypertension presents with abrupt, severe chest pain that radiates to the interscapular region. He describes the pain as tearing.

Vital signs:

BP: 198/108 mmHg in the right arm and 168/94 mmHg in the left arm
HR: 112/min
RR: 24/min

Examination reveals a new early diastolic murmur and a weaker left radial pulse. ECG shows nonspecific ST-T changes.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute Stanford type A aortic dissection

Abrupt maximal chest pain radiating to the back, pulse and blood-pressure asymmetry, and a new aortic-regurgitation murmur strongly suggest an ascending aortic dissection.

Q2

What is the most appropriate diagnostic imaging study in a hemodynamically stable patient?

ACT angiography of the chest, abdomen, and pelvisBExercise stress testingCCoronary calcium scoringDRoutine chest radiograph onlyEVentilation-perfusion scanning

Reveal answer and rationale

✓Correct answer: A. CT angiography of the chest, abdomen, and pelvis

CT angiography rapidly defines the extent of dissection and branch-vessel involvement. Transesophageal echocardiography is useful when the patient is unstable or cannot undergo CT.

Q3

Which initial medical strategy is generally appropriate while emergency surgical care is arranged?

AIntravenous beta-blockade followed by controlled blood-pressure reductionBImmediate thrombolysisCHigh-dose aspirin aloneDRapid intravenous fluid loading to hypertensionEOutpatient oral antihypertensive adjustment

Reveal answer and rationale

✓Correct answer: A. Intravenous beta-blockade followed by controlled blood-pressure reduction

Anti-impulse therapy reduces heart rate and aortic-wall stress. Vasodilator therapy may be added after adequate heart-rate control when needed.

Q4

What is the definitive management of an uncomplicated Stanford type A dissection?

AUrgent surgical repairBLong-term observation onlyCRoutine anticoagulationDOutpatient cardiac rehabilitationEBotanical vasodilator therapy

Reveal answer and rationale

✓Correct answer: A. Urgent surgical repair

Ascending-aortic involvement carries a high risk of rupture, tamponade, aortic regurgitation, and coronary or cerebral malperfusion and generally requires emergency surgery.

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Diagnosis: Acute Stanford type A aortic dissection

Key differentials

Acute coronary syndrome
Pulmonary embolism
Acute pericarditis
Esophageal rupture
Tension pneumothorax

Treatment principles

Emergency aortic-team activation
Rapid definitive imaging
Intravenous anti-impulse therapy
Urgent surgical repair for ascending-aortic involvement

Botanical safety: No botanical vasodilator or anticoagulant should delay emergency imaging or surgical assessment.

Clinical Pearl: A normal ECG or chest radiograph does not exclude aortic dissection.

NPLEX Trap: Do not administer thrombolytic therapy for presumed myocardial infarction until dissection has been considered when the presentation is suspicious.

Reference basis: ACC/AHA aortic-disease guidance.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 22

Tension PneumothoraxClinical Case 22

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 29-year-old man develops sudden severe dyspnea and right-sided chest pain after blunt chest trauma.

Vital signs:

BP: 78/46 mmHg
HR: 138/min
RR: 36/min
SpO₂: 82%

Examination reveals distended neck veins, absent breath sounds on the right, hyperresonance, and tracheal deviation to the left.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Tension pneumothorax

Unilateral absent breath sounds with obstructive shock and mediastinal shift after trauma is classic for tension pneumothorax.

Q2

What is the immediate management priority?

AImmediate thoracic decompression without waiting for imagingBObtain a routine chest radiograph before treatmentCAdminister an oral bronchodilatorDBegin chest physiotherapyEObserve for spontaneous improvement

Reveal answer and rationale

✓Correct answer: A. Immediate thoracic decompression without waiting for imaging

Tension pneumothorax is a clinical diagnosis in an unstable patient. Delaying decompression for imaging can be fatal.

Q3

What definitive procedure should follow emergency needle or finger decompression?

Reveal answer and rationale

✓Correct answer: A. Tube thoracostomy

A chest tube provides ongoing evacuation of pleural air after immediate decompression.

Q4

Which finding would be more typical of cardiac tamponade than tension pneumothorax?

AAbsent unilateral breath soundsBHyperresonanceCMuffled heart sounds with equal breath soundsDTracheal deviationESubcutaneous emphysema

Reveal answer and rationale

✓Correct answer: C. Muffled heart sounds with equal breath sounds

Both conditions can cause obstructive shock and neck-vein distention, but unilateral absent breath sounds and hyperresonance favor tension pneumothorax.

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Diagnosis: Tension pneumothorax with obstructive shock

Treatment principles

Immediate airway and breathing assessment
Emergency decompression based on clinical findings
Tube thoracostomy
Trauma evaluation and resuscitation

Physical medicine: Chest manipulation is contraindicated.

Clinical Pearl: Hypotension plus unilateral absent breath sounds is enough to act when tension pneumothorax is suspected.

NPLEX Trap: Do not wait for a chest radiograph in an unstable patient.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 23

Convulsive Status EpilepticusClinical Case 23

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 38-year-old woman with epilepsy has continuous generalized tonic-clonic activity lasting seven minutes. Her family reports that she missed several antiseizure doses.

Vital signs:

BP: 154/92 mmHg
HR: 132/min
SpO₂: 88%

Capillary glucose is 5.9 mmol/L.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Convulsive status epilepticus

A convulsive seizure lasting five minutes or longer should be treated as status epilepticus because spontaneous termination becomes less likely and complications increase.

Q2

What is the first-line medication class?

Reveal answer and rationale

✓Correct answer: A. Benzodiazepine

Rapid benzodiazepine treatment is first-line while airway, oxygenation, circulation, and reversible causes are addressed.

Q3

What is an appropriate next treatment if convulsions continue after adequate benzodiazepine therapy?

AA loading dose of an appropriate intravenous antiseizure medicationBDelay treatment for EEG confirmationCOral magnesium onlyDImmediate dischargeEAcupuncture

Reveal answer and rationale

✓Correct answer: A. A loading dose of an appropriate intravenous antiseizure medication

Established status epilepticus requires prompt second-line antiseizure therapy and escalation to critical care if seizures persist.

Q4

Which bedside test should be performed immediately in every patient with ongoing seizure activity?

Reveal answer and rationale

✓Correct answer: A. Capillary blood glucose

Hypoglycemia is a rapidly reversible cause of seizures and should be checked immediately.

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Diagnosis: Convulsive status epilepticus

Immediate priorities

Protect airway and oxygenation
Check glucose
Administer a benzodiazepine promptly
Give second-line intravenous antiseizure therapy when required
Identify missed medication, infection, toxins, electrolyte disturbance, pregnancy-related causes, or structural brain disease

Botanical safety: No botanical or supplement should delay anticonvulsant treatment.

Clinical Pearl: Treat at five minutes rather than waiting for thirty minutes.

NPLEX Trap: Do not place objects in the patient’s mouth or physically restrain convulsive movements.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 24

Acute Ascending CholangitisClinical Case 24

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 72-year-old woman with known gallstones presents with fever, right-upper-quadrant pain, jaundice, and confusion.

Vital signs:

BP: 84/50 mmHg
HR: 126/min
Temperature: 39.3°C

Laboratory findings show leukocytosis, elevated bilirubin, and a cholestatic liver-enzyme pattern.

Q1

What is the most likely diagnosis?

AUncomplicated biliary colicBAcute ascending cholangitis with septic shockCAcute viral hepatitisDIrritable bowel syndromeEUncomplicated cholelithiasis

Reveal answer and rationale

✓Correct answer: B. Acute ascending cholangitis with septic shock

Fever, right-upper-quadrant pain, jaundice, hypotension, and altered mental status indicate severe biliary infection and obstruction.

Q2

What is the most appropriate immediate management?

ASepsis resuscitation, intravenous antibiotics, and urgent biliary drainageBOutpatient ultrasound next weekCOral antacid therapyDHigh-fat feedingEBotanical cholagogue treatment

Reveal answer and rationale

✓Correct answer: A. Sepsis resuscitation, intravenous antibiotics, and urgent biliary drainage

Severe cholangitis requires urgent stabilization, antimicrobial treatment, and source control through biliary decompression.

Q3

Which procedure is commonly used for urgent biliary decompression?

Reveal answer and rationale

✓Correct answer: A. ERCP

Endoscopic retrograde cholangiopancreatography can relieve obstruction and permit drainage.

Q4

Which naturopathic intervention is inappropriate during suspected biliary obstruction?

ACholeretic or cholagogue herbsBEmergency referralCMedication reconciliationDMonitoring vital signsECommunicating allergy history

Reveal answer and rationale

✓Correct answer: A. Choleretic or cholagogue herbs

Products that stimulate bile flow are not substitutes for urgent source control and may aggravate symptoms in obstruction.

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Diagnosis: Severe acute ascending cholangitis

Key investigations

CBC and lactate
Liver enzymes and bilirubin
Renal function and coagulation testing
Blood cultures
Abdominal ultrasound
Cross-sectional biliary imaging when needed

Treatment principles

Sepsis resuscitation
Intravenous antimicrobials
Urgent biliary drainage
Definitive management of stones or obstruction

Clinical Pearl: Charcot triad plus hypotension and confusion indicates severe disease.

NPLEX Trap: Do not wait for complete imaging when the patient is unstable and urgent source control is required.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 25

Necrotizing Soft-Tissue InfectionClinical Case 25

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 57-year-old man with diabetes presents with rapidly worsening pain and swelling of the left leg after a small skin abrasion.

Vital signs:

BP: 86/52 mmHg
HR: 128/min
Temperature: 39.2°C

The leg is tense and erythematous with dusky bullae. Pain is severe and extends beyond the visibly affected skin.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Necrotizing soft-tissue infection

Rapid progression, pain out of proportion, systemic toxicity, bullae, and skin discoloration are red flags for necrotizing infection.

Q2

What is the most important immediate intervention?

AUrgent surgical exploration and debridementBTopical antibiotic onlyCWait for MRI confirmationDCompression stockingsEOutpatient oral therapy

Reveal answer and rationale

✓Correct answer: A. Urgent surgical exploration and debridement

Definitive diagnosis and treatment are surgical. Imaging must not delay operative management when clinical suspicion is high.

Q3

What antimicrobial approach is appropriate initially?

ABroad-spectrum intravenous therapy covering gram-positive, gram-negative, and anaerobic organismsBPenicillin V alone for every patientCNo antibiotics until tissue culture returnsDTopical antifungal therapyEOral doxycycline only

Reveal answer and rationale

✓Correct answer: A. Broad-spectrum intravenous therapy covering gram-positive, gram-negative, and anaerobic organisms

Empiric therapy must be broad and then narrowed according to operative cultures and the identified pathogen.

Q4

Which finding most strongly differentiates necrotizing infection from uncomplicated cellulitis?

APain out of proportion with rapid progressionBMild localized warmthCPruritusDStable vital signsELong-standing pigmentation

Reveal answer and rationale

✓Correct answer: A. Pain out of proportion with rapid progression

Severe pain, systemic illness, bullae, crepitus, anesthesia, and rapid spread should trigger emergency surgical assessment.

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Diagnosis: Necrotizing soft-tissue infection with septic shock

Treatment principles

Immediate surgical consultation
Repeated debridement as needed
Broad-spectrum intravenous antibiotics
Hemodynamic resuscitation
Intensive-care monitoring

Botanical and physical medicine safety: Do not use poultices, massage, hydrotherapy, or topical treatments in place of surgery.

Clinical Pearl: Early skin changes may appear deceptively mild despite deep fascial destruction.

NPLEX Trap: A normal or nondiagnostic imaging study does not override a strongly suspicious clinical presentation.

Reference basis: IDSA skin and soft-tissue infection guidance.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 26

Acute Cardiogenic Pulmonary EdemaClinical Case 26

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 74-year-old man with ischemic cardiomyopathy presents with severe breathlessness, orthopnea, and pink frothy sputum.

Vital signs:

BP: 188/112 mmHg
HR: 118/min
RR: 34/min
SpO₂: 80%

Examination reveals diffuse crackles, elevated jugular venous pressure, and bilateral leg edema.

Q1

What is the most likely diagnosis?

AAcute cardiogenic pulmonary edemaBStable chronic heart failureCAcute bronchitisDPanic attackEUncomplicated pleural effusion

Reveal answer and rationale

✓Correct answer: A. Acute cardiogenic pulmonary edema

Severe hypoxemia, orthopnea, diffuse crackles, frothy sputum, and congestion indicate acute decompensated left-sided heart failure.

Q2

What is the immediate respiratory support priority?

ASupplemental oxygen and noninvasive positive-pressure ventilation when appropriateBRoutine chest physiotherapyCOral antihistamineDIncentive spirometry onlyENo respiratory support

Reveal answer and rationale

✓Correct answer: A. Supplemental oxygen and noninvasive positive-pressure ventilation when appropriate

Positive-pressure support can improve oxygenation and reduce work of breathing in appropriate patients while definitive therapy is started.

Q3

Which medication is commonly used to reduce congestion when volume overload is present?

Reveal answer and rationale

✓Correct answer: A. Intravenous loop diuretic

Loop diuretics are used to relieve pulmonary and systemic congestion, with dosing individualized to prior exposure and renal function.

Q4

Which botanical product may worsen fluid retention and blood pressure?

Reveal answer and rationale

✓Correct answer: A. Licorice

Glycyrrhizin-containing licorice can cause sodium retention, hypokalemia, and hypertension.

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Diagnosis: Acute cardiogenic pulmonary edema

Key assessments

ECG and cardiac biomarkers
Chest imaging
Electrolytes and renal function
Echocardiography when indicated
Evaluation for acute coronary syndrome, arrhythmia, infection, or medication nonadherence

Treatment principles

Oxygen for hypoxemia
Noninvasive ventilation when appropriate
Intravenous diuresis
Vasodilator therapy in selected hypertensive patients
Treat the precipitating cause

Clinical Pearl: Pink frothy sputum is a late and severe sign.

NPLEX Trap: Do not give large empiric fluid boluses to a clearly congested patient unless another indication is present.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 27

Severe Community-Acquired Pneumonia With Septic ShockClinical Case 27

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 68-year-old woman presents with fever, productive cough, pleuritic pain, confusion, and progressive shortness of breath.

Vital signs:

BP: 80/48 mmHg
HR: 124/min
RR: 32/min
SpO₂: 86%

Chest examination reveals bronchial breath sounds and crackles over the right lower lobe. Lactate is elevated.

Q1

What is the most likely diagnosis?

AMild outpatient bronchitisBSevere community-acquired pneumonia with septic shockCStable COPDDPulmonary fibrosisEAllergic rhinitis

Reveal answer and rationale

✓Correct answer: B. Severe community-acquired pneumonia with septic shock

Focal lung findings, hypoxemia, hypotension, confusion, and elevated lactate indicate severe pneumonia with organ dysfunction and shock.

Q2

What is the most appropriate management?

AEmergency hospitalization, sepsis resuscitation, oxygen, and prompt intravenous antibioticsBHome treatment with cough syrupCWait for sputum culture before antibioticsDBreathing exercises onlyEBotanical antimicrobial monotherapy

Reveal answer and rationale

✓Correct answer: A. Emergency hospitalization, sepsis resuscitation, oxygen, and prompt intravenous antibiotics

Severe pneumonia requires immediate stabilization and empiric antimicrobial treatment after cultures when feasible without causing delay.

Q3

Which investigation confirms a pulmonary infiltrate?

Reveal answer and rationale

✓Correct answer: A. Chest radiograph

Chest imaging supports the diagnosis, identifies complications, and helps distinguish alternative causes.

Q4

Which finding is a marker of severe disease?

Reveal answer and rationale

✓Correct answer: A. Need for vasopressor support

Shock requiring vasopressors is a major severity feature and generally requires intensive-care management.

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Diagnosis: Severe community-acquired pneumonia with septic shock

Treatment principles

Oxygen and ventilatory support
Sepsis resuscitation
Timely empiric intravenous antibiotics
Cultures when feasible without delaying therapy
Evaluation for pleural infection and other complications

Botanical safety: No botanical antimicrobial should replace hospital treatment.

Clinical Pearl: Older adults may present primarily with confusion or functional decline.

NPLEX Trap: Do not classify pneumonia as mild solely because the fever is modest.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 28

Serotonin SyndromeClinical Case 28

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 32-year-old woman taking sertraline develops agitation, sweating, diarrhea, tremor, and fever several hours after starting linezolid.

Vital signs:

BP: 162/94 mmHg
HR: 132/min
Temperature: 39.1°C

Examination reveals inducible clonus, ocular clonus, hyperreflexia, and increased bowel sounds.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Serotonin syndrome

Rapid onset after serotonergic drug interaction with clonus, hyperreflexia, autonomic instability, and gastrointestinal hyperactivity is characteristic.

Q2

What is the first management step?

AStop serotonergic agents and provide urgent supportive careBAdminister another SSRICBegin levodopaDGive an anticholinergic drugEDischarge with reassurance

Reveal answer and rationale

✓Correct answer: A. Stop serotonergic agents and provide urgent supportive care

Offending agents must be stopped. Management includes sedation, cooling, fluids, and escalation for severe hyperthermia or organ complications.

Q3

Which physical finding most strongly favors serotonin syndrome over neuroleptic malignant syndrome?

AClonus and hyperreflexiaBLead-pipe rigidity with bradyreflexiaCDry skin and urinary retentionDPinpoint pupilsEFlaccid paralysis

Reveal answer and rationale

✓Correct answer: A. Clonus and hyperreflexia

Serotonin toxicity commonly produces neuromuscular hyperactivity, especially clonus and hyperreflexia.

Q4

Which supplement is clinically important because it may contribute to serotonergic toxicity?

Reveal answer and rationale

✓Correct answer: A. St. John’s wort

St. John’s wort has serotonergic and major drug-interaction effects and should be documented when patients use antidepressants or other serotonergic agents.

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Diagnosis: Serotonin syndrome caused by a drug interaction

Potential contributors

SSRIs and SNRIs
Monoamine-oxidase inhibition
Certain opioids
Dextromethorphan
Linezolid
St. John’s wort

Treatment principles

Stop causative agents
Support airway, breathing, and circulation
Benzodiazepine sedation
Active cooling for hyperthermia
Specialist toxicology or critical-care support for severe cases

Clinical Pearl: The onset is usually rapid after a dose increase, overdose, or interaction.

NPLEX Trap: Antipyretics do not correct hyperthermia driven by excessive muscle activity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 29

Ovarian TorsionClinical Case 29

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 24-year-old woman presents with sudden severe right-sided pelvic pain, nausea, and vomiting. Ultrasound shows an enlarged right ovary with a 7-cm cyst and reduced venous flow. Pregnancy testing is negative.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Ovarian torsion

Sudden unilateral pelvic pain with vomiting and an enlarged ovary or adnexal mass strongly suggests torsion.

Q2

What is the most appropriate next step?

AUrgent gynecologic surgical assessmentBRepeat ultrasound in one monthCBegin oral antibiotics onlyDPelvic manipulationEHome observation

Reveal answer and rationale

✓Correct answer: A. Urgent gynecologic surgical assessment

Torsion threatens ovarian viability and requires timely diagnostic laparoscopy and detorsion when suspected.

Q3

Which statement about Doppler ultrasound is correct?

ANormal arterial flow does not completely exclude torsionBNormal flow rules out torsion with certaintyCDoppler has no roleDOnly CT can diagnose torsionEUltrasound should be delayed until pain resolves

Reveal answer and rationale

✓Correct answer: A. Normal arterial flow does not completely exclude torsion

Intermittent torsion and dual ovarian blood supply can produce preserved flow; management depends on the full clinical picture.

Q4

Which intervention is inappropriate?

ADelaying referral for botanical or manual treatmentBProviding analgesia while arranging careCChecking pregnancy statusDMaintaining fasting statusEMonitoring vital signs

Reveal answer and rationale

✓Correct answer: A. Delaying referral for botanical or manual treatment

No complementary intervention should delay surgical assessment in suspected torsion.

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Disease Review & Exam Traps

Diagnosis: Ovarian torsion associated with an adnexal cyst

Key differentials

Ectopic pregnancy
Ruptured ovarian cyst
Appendicitis
Pelvic inflammatory disease
Renal colic

Treatment principles

Urgent gynecologic consultation
Diagnostic laparoscopy
Detorsion and ovarian preservation when feasible
Management of the associated mass

Clinical Pearl: Pain may be intermittent when the adnexa twists and untwists.

NPLEX Trap: Preserved Doppler flow does not reliably exclude torsion.

Reference basis: ACOG guidance on adnexal torsion.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 30

Cauda Equina SyndromeClinical Case 30

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 48-year-old man with a large lumbar-disc herniation presents with worsening low-back pain, bilateral leg weakness, numbness in the saddle region, and new urinary retention. Rectal tone is reduced.

Q1

What is the most likely diagnosis?

AUncomplicated mechanical low-back painBCauda equina syndromeCPiriformis syndromeDPeripheral neuropathy onlyEAnkylosing spondylitis

Reveal answer and rationale

✓Correct answer: B. Cauda equina syndrome

Urinary retention, saddle anesthesia, bilateral neurologic deficits, and reduced anal tone indicate compression of the cauda equina.

Q2

What is the most appropriate next step?

AEmergency MRI and urgent spine-surgical assessmentBRoutine physiotherapy referralCLumbar manipulationDOutpatient radiograph next monthEBed rest at home

Reveal answer and rationale

✓Correct answer: A. Emergency MRI and urgent spine-surgical assessment

Rapid imaging and surgical evaluation are required to prevent permanent bladder, bowel, sexual, and motor dysfunction.

Q3

Which symptom is a major red flag?

ANew urinary retentionBPain improving with restCMild paraspinal tendernessDLong-standing stiffnessEIsolated hamstring tightness

Reveal answer and rationale

✓Correct answer: A. New urinary retention

Acute bladder dysfunction is a key warning sign of severe sacral nerve-root compression.

Q4

Which physical-medicine intervention is contraindicated?

AHigh-velocity lumbar manipulationBNeutral positioning during transferCDocumenting lower-limb strengthDEmergency referralEMonitoring for progression

Reveal answer and rationale

✓Correct answer: A. High-velocity lumbar manipulation

Manipulation should not be performed when a compressive neurologic emergency is suspected.

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Diagnosis: Cauda equina syndrome caused by lumbar-disc compression

Red flags

Urinary retention or overflow incontinence
Saddle anesthesia
Bilateral sciatica or weakness
Reduced anal tone
Bowel or sexual dysfunction

Treatment principles

Emergency MRI
Urgent spine-surgical consultation
Timely decompression when confirmed
Bladder and neurologic monitoring

Physical medicine: Spinal manipulation is contraindicated.

Clinical Pearl: Urinary retention may precede overflow incontinence.

NPLEX Trap: Do not label bilateral symptoms and bladder dysfunction as routine sciatica.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 31

Aneurysmal Subarachnoid HemorrhageClinical Case 31

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 51-year-old woman presents with a sudden severe headache that began while exercising 30 minutes ago. She describes it as: “The worst headache of my life.” Associated symptoms include:

Vomiting
Photophobia
Neck stiffness
Brief loss of consciousness Vital signs:
BP: 186/104 mmHg
HR: 58/min
RR: 20/min
SpO₂: 97% Physical examination:
Appears distressed
Nuchal rigidity
Mild confusion
No focal limb weakness

Q1

What is the most likely diagnosis?

ATension-type headacheBAneurysmal subarachnoid hemorrhageCAcute bacterial sinusitisDMigraine without complicationECluster headache

Reveal answer and rationale

✓Correct answer: B. Aneurysmal subarachnoid hemorrhage

A sudden thunderclap headache reaching maximal intensity within seconds, accompanied by vomiting, meningismus, altered consciousness, and exertional onset, strongly suggests subarachnoid hemorrhage. Why the Other Options Are Incorrect

A. Tension headache: Usually gradual, bilateral, and non-incapacitating.
C. Sinusitis: Produces facial pressure and nasal symptoms rather than abrupt maximal headache.
D. Migraine: May be severe but typically evolves more gradually and should not be assumed in a new thunderclap presentation.
E. Cluster headache: Causes unilateral orbital pain with autonomic symptoms but not usually neck stiffness or loss of consciousness.

Q2

What is the most appropriate initial investigation?

Reveal answer and rationale

✓Correct answer: A. Noncontrast CT of the head

Urgent noncontrast head CT is the initial imaging study for suspected subarachnoid hemorrhage. If CT is nondiagnostic but clinical suspicion remains high, further evaluation may include lumbar puncture or vascular imaging, depending on presentation timing and local protocol.

Q3

Which medication is used after aneurysmal subarachnoid hemorrhage to reduce the risk of delayed cerebral ischemia?

Reveal answer and rationale

✓Correct answer: A. Nimodipine

Enteral nimodipine is used after aneurysmal subarachnoid hemorrhage because it improves neurologic outcomes associated with delayed cerebral ischemia.

Q4

Which action is inappropriate?

AEmergency neurologic referralBCareful airway and blood-pressure managementCGiving a triptan and sending the patient homeDUrgent vascular evaluationEMonitoring for neurologic deterioration

Reveal answer and rationale

✓Correct answer: C. Giving a triptan and sending the patient home

A new thunderclap headache must be treated as a potentially life-threatening vascular event. Migraine treatment should not delay urgent investigation.

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Diagnosis: Suspected aneurysmal subarachnoid hemorrhage

Key differentials

Reversible cerebral vasoconstriction syndrome
Cervical artery dissection
Cerebral venous sinus thrombosis
Pituitary apoplexy
Meningitis
Migraine
Hypertensive intracranial hemorrhage

Key investigations

Noncontrast head CT
CT angiography
Lumbar puncture when indicated
CBC
Electrolytes
Coagulation studies
ECG and cardiac biomarkers

Treatment principles

Emergency neurologic and neurosurgical management
Secure the aneurysm through endovascular or surgical treatment
Nimodipine
Careful blood-pressure management
Management of hydrocephalus
Monitoring for rebleeding and delayed cerebral ischemia The AHA/ASA guideline emphasizes rapid identification, specialized neurocritical care, early aneurysm treatment, and measures to reduce delayed cerebral ischemia.

Botanical and pharmacologic safety: Avoid supplements or medications that increase bleeding risk until intracranial hemorrhage has been evaluated.

Clinical Pearl: A normal neurologic examination does not exclude subarachnoid hemorrhage.

NPLEX Trap: Do not diagnose migraine in a patient with a first or worst thunderclap headache without emergency investigation.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 32

Acute Kidney InjuryClinical Case 32

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 74-year-old woman presents with weakness, nausea, and reduced urine output. Three days ago, she developed vomiting and diarrhea. She continued taking:

Ramipril
Hydrochlorothiazide
Ibuprofen for knee pain
Metformin Vital signs:
BP: 88/54 mmHg
HR: 112/min
Dry mucous membranes Laboratory findings:
Creatinine: 286 µmol/L; baseline 82 µmol/L
Urea: elevated
Potassium: 5.8 mmol/L
Bicarbonate: 17 mmol/L
Urinalysis: concentrated urine without heavy protein or blood

Q1

What is the most likely diagnosis?

AChronic kidney disease without acute changeBAcute kidney injury caused by volume depletion and medication effectsCNephrotic syndromeDUncomplicated cystitisEDiabetes insipidus

Reveal answer and rationale

✓Correct answer: B. Acute kidney injury caused by volume depletion and medication effects

The abrupt creatinine increase, oliguria, hypotension, gastrointestinal fluid losses, and continued use of medications that affect renal perfusion strongly indicate acute kidney injury.

The combination of an ACE inhibitor, diuretic, and NSAID is particularly concerning during dehydration.

Q2

What is the most appropriate initial management?

AIncrease ibuprofen for painBAssess volume status, stop contributing nephrotoxic medications, provide appropriate fluid resuscitation, and monitor electrolytesCRestrict all fluid regardless of examination findingsDIncrease ramiprilEBegin a high-protein diet

Reveal answer and rationale

✓Correct answer: B. Assess volume status, stop contributing nephrotoxic medications, provide appropriate fluid resuscitation, and monitor electrolytes

Management includes restoring renal perfusion when volume depletion is present, reviewing medications, treating the precipitating cause, and monitoring for dangerous complications.

Q3

Which medication should be withheld because accumulation during significant acute kidney dysfunction may increase the risk of lactic acidosis?

Reveal answer and rationale

✓Correct answer: A. Metformin

Metformin is generally withheld during significant acute kidney injury, severe dehydration, hypoxia, or hemodynamic instability because impaired clearance increases the risk of metformin-associated lactic acidosis.

Q4

Which finding is an urgent indication for renal-replacement therapy assessment?

AMild nausea onlyBRefractory hyperkalemia with ECG changesCCreatinine above the laboratory reference range aloneDConcentrated urineEAge older than 65 years

Reveal answer and rationale

✓Correct answer: B. Refractory hyperkalemia with ECG changes

Urgent dialysis assessment may be required for:

Refractory acidosis
Severe electrolyte disturbance
Certain toxic ingestions
Fluid overload causing respiratory compromise
Symptomatic uremia

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Diagnosis: Acute kidney injury caused by dehydration and impaired renal autoregulation

Major categories

Prerenal: reduced renal perfusion
Intrinsic renal: tubular, glomerular, interstitial, or vascular injury
Postrenal: urinary obstruction

Key investigations

Serial creatinine and urine output
Electrolytes and bicarbonate
Urinalysis and microscopy
Medication review
Bladder scan
Renal ultrasound when obstruction is possible
Creatine kinase when rhabdomyolysis is suspected

Treatment principles

Correct hypovolemia
Stop nephrotoxic or contributing medications
Treat infection or obstruction
Adjust medication doses
Monitor potassium and acid-base status
Assess for dialysis indications

Botanical safety: Herbal diuretics and poorly characterized supplements can worsen dehydration or contain nephrotoxic substances.

Clinical Pearl: Creatinine can continue to increase after the original renal insult.

NPLEX Trap: Do not prescribe large fluid volumes without assessing whether the patient has hypovolemia, heart failure, or obstruction.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 33

Small-Bowel ObstructionClinical Case 33

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 66-year-old man presents with cramping abdominal pain, vomiting, abdominal distension, and inability to pass stool or gas. History:

Open appendectomy
Partial colectomy 10 years ago Vital signs:

BP: 102/66 mmHg
HR: 114/min
Temperature: 37.8°C Physical examination:
Distended abdomen
High-pitched bowel sounds
Diffuse tenderness
No stool in the rectal vault Laboratory findings:
Mild leukocytosis
Hypokalemia
Elevated urea

Q1

What is the most likely diagnosis?

AIrritable bowel syndromeBMechanical small-bowel obstructionCUncomplicated constipationDAcute hepatitisEGastroesophageal reflux disease

Reveal answer and rationale

✓Correct answer: B. Mechanical small-bowel obstruction

Colicky pain, vomiting, distension, obstipation, previous abdominal surgery, and high-pitched bowel sounds support mechanical bowel obstruction, likely caused by adhesions.

Q2

What is the most appropriate initial management?

AAdminister a stimulant laxativeBKeep the patient fasting, provide intravenous fluids and electrolyte correction, decompress when indicated, and obtain urgent surgical assessmentCBegin a high-fibre dietDPerform abdominal massageERecommend oral hydration at home

Reveal answer and rationale

✓Correct answer: B. Keep the patient fasting, provide intravenous fluids and electrolyte correction, decompress when indicated, and obtain urgent surgical assessment

Management includes bowel rest, fluid resuscitation, electrolyte correction, symptom control, decompression, imaging, and evaluation for surgical intervention.

Q3

Which finding raises the greatest concern for bowel strangulation or ischemia?

AIntermittent cramping onlyBConstant severe pain, fever, peritoneal signs, and increasing lactateCHigh-pitched bowel soundsDPrevious abdominal surgeryEMild hypokalemia

Reveal answer and rationale

✓Correct answer: B. Constant severe pain, fever, peritoneal signs, and increasing lactate

Continuous pain, guarding, rebound tenderness, fever, hemodynamic instability, metabolic acidosis, or rising lactate may indicate compromised blood supply and require urgent surgery.

Q4

Which intervention should be avoided?

AIntravenous fluid replacementBSurgical consultationCStimulant laxatives and vigorous abdominal manipulationDElectrolyte monitoringENasogastric decompression when indicated

Reveal answer and rationale

✓Correct answer: C. Stimulant laxatives and vigorous abdominal manipulation

Laxatives or manipulation may worsen pain, increase pressure, and delay definitive treatment when a mechanical obstruction is present.

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Diagnosis: Adhesive small-bowel obstruction

Common causes

Postoperative adhesions
Hernia
Malignancy
Crohn disease
Volvulus
Intussusception

Key investigations

CBC
Electrolytes and renal function
Lactate
Abdominal CT
Plain radiography in selected settings
Hernia examination

Treatment principles

Fasting
Intravenous fluids
Electrolyte correction
Nasogastric decompression when indicated

Serial abdominal examinations
Urgent surgery for strangulation, perforation, or failed conservative care

Clinical Pearl: Bowel sounds may become reduced or absent when obstruction progresses or ischemia develops.

NPLEX Trap: Complete obstipation and vomiting should not be managed as routine constipation.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 34

Preeclampsia with Severe FeaturesClinical Case 34

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 32-year-old pregnant woman at 35 weeks’ gestation presents with severe headache, blurred vision, and right-upper-quadrant pain. Vital signs:

BP: 172/114 mmHg
Repeat BP: 168/110 mmHg
HR: 92/min Physical examination:
Facial and hand edema
Brisk deep-tendon reflexes
Right-upper-quadrant tenderness Laboratory findings:
Platelets: 86 × 10⁹/L
AST: elevated
Creatinine: elevated from baseline
Urine protein: elevated

Q1

What is the most likely diagnosis?

AGestational hypertension without severe featuresBPreeclampsia with severe featuresCChronic uncomplicated hypertensionDNormal physiologic pregnancy changesEMigraine only

Reveal answer and rationale

✓Correct answer: B. Preeclampsia with severe features

Severe hypertension with neurologic symptoms, right-upper-quadrant pain, thrombocytopenia, hepatic injury, kidney dysfunction, and proteinuria indicates preeclampsia with severe features. Proteinuria is not required when other qualifying organ manifestations are present.

Q2

Which medication is used to prevent or treat eclamptic seizures?

AMagnesium sulfateBPhenytoin as routine first-line prophylaxisCAspirin at treatment dosesDDiazepam for long-term prophylaxisEPotassium chloride

Reveal answer and rationale

✓Correct answer: A. Magnesium sulfate

Magnesium sulfate is the standard medication for seizure prophylaxis in preeclampsia with severe features and treatment of eclampsia.

Q3

Which blood-pressure treatment principle is appropriate?

ASevere persistent hypertension should be treated urgently with an appropriate rapid-acting antihypertensiveBTreatment should wait until after deliveryCBotanical diuretics should be used firstDBlood pressure should be ignored if proteinuria is mildESodium restriction alone is adequate

Reveal answer and rationale

✓Correct answer: A. Severe persistent hypertension should be treated urgently with an appropriate rapid-acting antihypertensive

Severe persistent hypertension during pregnancy raises the risk of maternal stroke and other complications and requires urgent treatment.

Q4

What is the definitive treatment for preeclampsia?

ADelivery after maternal stabilization and obstetric assessmentBLong-term bed restCHigh-dose vitamin CDHerbal diureticsEElimination diet

Reveal answer and rationale

✓Correct answer: A. Delivery after maternal stabilization and obstetric assessment

Delivery is the definitive treatment. Timing depends on gestational age, disease severity, maternal condition, fetal condition, and response to stabilization. ACOG identifies severe hypertension, thrombocytopenia, impaired liver function, renal insufficiency, pulmonary edema, severe headache, and visual symptoms as severe features requiring urgent obstetric management.

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Diagnosis: Preeclampsia with severe features, with possible evolving HELLP syndrome

Severe features include

Severe persistent hypertension
Thrombocytopenia
Liver dysfunction
Severe right-upper-quadrant or epigastric pain
Renal insufficiency
Pulmonary edema
New severe headache
Visual disturbance

Key investigations

Serial blood-pressure measurements
CBC and platelets
Liver enzymes
Creatinine
Urine protein assessment
Fetal monitoring
Ultrasound assessment when indicated

Treatment principles

Immediate obstetric assessment
Magnesium sulfate
Urgent treatment of severe hypertension
Maternal and fetal monitoring
Delivery after stabilization when indicated

Botanical safety: Diuretic or uterine-stimulating herbs must not replace emergency obstetric management.

Clinical Pearl: Sudden edema is not diagnostic, but facial or hand swelling may support the clinical picture.

NPLEX Trap: Preeclampsia can be diagnosed without proteinuria when severe organ dysfunction is present.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 35

Opioid OverdoseClinical Case 35

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 38-year-old man is found unresponsive in a washroom. An empty packet containing an unknown powder is nearby. Assessment:

Respiratory rate: 5/min
SpO₂: 78%
HR: 54/min
BP: 94/58 mmHg
Pupils: pinpoint
Minimal response to painful stimulation

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Opioid overdose

The classic opioid toxidrome includes:

Depressed consciousness
Respiratory depression
Pinpoint pupils Bradycardia and hypotension may also occur.

Q2

What is the immediate management priority?

AWait for toxicology confirmationBSupport ventilation, administer naloxone, and activate emergency servicesCGive activated charcoal before supporting breathingDPlace the patient in a cold showerEInduce vomiting

Reveal answer and rationale

✓Correct answer: B. Support ventilation, administer naloxone, and activate emergency services

Airway and ventilation are the immediate priorities. Naloxone should be administered promptly when opioid overdose is suspected. CDC guidance advises administering naloxone when opioid overdose is suspected, activating emergency response, supporting breathing, and remaining with the individual because recurrent toxicity can occur.

Q3

Why may repeated naloxone doses be necessary?

ANaloxone causes permanent opioid toleranceBPotent or long-acting opioids may outlast naloxone’s duration of actionCNaloxone does not affect opioid receptorsDNaloxone works only for oral opioidsENaloxone is ineffective against fentanyl

Reveal answer and rationale

✓Correct answer: B. Potent or long-acting opioids may outlast naloxone’s duration of action

Recurrent respiratory depression may occur because some opioids remain active longer than naloxone. Multiple doses may also be required with potent synthetic opioids.

Q4

What is the most important endpoint of naloxone treatment?

AComplete immediate wakefulnessBRestoration of adequate spontaneous ventilationCInduction of severe withdrawalDNormalization of pupil sizeEElimination of all pain

Reveal answer and rationale

✓Correct answer: B. Restoration of adequate spontaneous ventilation

Naloxone should be titrated to restore effective breathing. Complete arousal is not always required and may provoke severe withdrawal, agitation, vomiting, or sympathetic stress.

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Diagnosis: Life-threatening opioid overdose

Typical findings

Depressed consciousness
Slow or absent respiration
Pinpoint pupils
Cyanosis
Snoring or gurgling
Bradycardia
Hypotension

Treatment principles

Activate emergency services
Open and protect the airway
Provide rescue breathing or ventilation
Administer naloxone
Repeat naloxone when necessary

Monitor for recurrent toxicity
Evaluate for aspiration, pulmonary edema, trauma, and co-ingestions

Long-term management

Nonjudgmental overdose counseling
Take-home naloxone
Assessment for opioid-use disorder
Evidence-based medications for opioid-use disorder
Harm-reduction education

Clinical Pearl: Normal pupil size does not exclude opioid overdose, especially with mixed ingestions or eye disease.

NPLEX Trap: Do not delay ventilation while searching for naloxone.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 36

Acute Limb IschemiaClinical Case 36

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 69-year-old man with atrial fibrillation presents with sudden severe pain in his left leg. He stopped taking apixaban one month ago. Physical examination of the left leg:

Pale
Cold
Absent dorsalis pedis and posterior tibial pulses
Reduced sensation
Weak ankle movement The right leg is warm with palpable pulses.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute limb ischemia

Sudden pain, pallor, pulselessness, paresthesia, paralysis, and poikilothermia are classic findings of acute arterial occlusion. The likely cause is an embolus related to atrial fibrillation.

Q2

What is the most appropriate immediate action?

AApply compression stockingsBArrange emergency vascular assessment and initiate anticoagulation when not contraindicatedCMassage the legDApply iceERecommend walking exercises

Reveal answer and rationale

✓Correct answer: B. Arrange emergency vascular assessment and initiate anticoagulation when not contraindicated

Acute limb ischemia threatens limb viability. Immediate anticoagulation and urgent revascularization assessment are generally required.

Q3

Which finding indicates a particularly threatened limb?

AMild pain with preserved sensationBMotor weakness and sensory lossCChronic skin pigmentationDBilateral ankle edemaEVaricose veins

Reveal answer and rationale

✓Correct answer: B. Motor weakness and sensory loss

Neurologic deficits indicate advanced ischemia and a rapidly narrowing window for limb salvage.

Q4

Which intervention is contraindicated?

AVascular consultationBDoppler assessmentCVigorous massage or compression of the ischemic extremityDAnticoagulation assessmentEPain management

Reveal answer and rationale

✓Correct answer: C. Vigorous massage or compression of the ischemic extremity

Massage or compression does not restore arterial flow and could delay definitive revascularization or worsen tissue injury.

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Diagnosis: Acute embolic limb ischemia

The six Ps

Pain
Pallor
Pulselessness
Paresthesia
Paralysis
Poikilothermia

Common causes

Cardioembolic disease
Thrombosis of peripheral arterial disease
Aneurysm thrombosis
Graft occlusion
Arterial dissection
Trauma

Key investigations

Immediate vascular examination
Handheld Doppler
CT angiography when it will not delay treatment
ECG
CBC and coagulation studies
Renal function
Creatine kinase and lactate

Treatment principles

Immediate anticoagulation when appropriate
Urgent vascular consultation
Catheter-directed treatment, thrombectomy, bypass, or other revascularization
Monitoring for reperfusion injury and compartment syndrome

Clinical Pearl: Paralysis is a late and ominous finding.

NPLEX Trap: Do not confuse a cold, pale, pulseless limb with DVT, which more often causes warmth, edema, and preserved arterial pulses.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 37

Delirium Due to Urinary Infection and Medication EffectsClinical Case 37

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

An 82-year-old woman is brought by her daughter because of sudden confusion and visual hallucinations. Two days ago, she was prescribed diphenhydramine for insomnia. Medical history:

Mild cognitive impairment
Urinary incontinence
Hypertension Vital signs:
BP: 132/74 mmHg
HR: 106/min
Temperature: 38.3°C Physical examination:
Inattentive
Disoriented
Fluctuating level of alertness
Suprapubic tenderness
Dry mouth
Distended bladder

Q1

What is the most likely diagnosis?

AProgressive dementiaBDelirium caused by acute illness and anticholinergic medicationCPrimary psychotic disorderDMajor depressive disorderENormal aging

Reveal answer and rationale

✓Correct answer: B. Delirium caused by acute illness and anticholinergic medication

Acute onset, fluctuating consciousness, impaired attention, fever, urinary symptoms, and recent exposure to an anticholinergic medication indicate delirium.

Q2

Which feature best distinguishes delirium from dementia?

AMemory impairmentBAcute fluctuating inattention and altered awarenessCOlder ageDDifficulty performing daily activitiesEPresence of vascular risk factors

Reveal answer and rationale

✓Correct answer: B. Acute fluctuating inattention and altered awareness

Delirium develops over hours to days and fluctuates. Dementia generally develops gradually and does not initially produce major fluctuations in attention or consciousness.

Q3

What is the most appropriate management?

ABegin a long-term antipsychotic without investigationBIdentify and treat underlying causes, stop contributing medications, provide orientation, hydration, mobility, and sleep supportCRestrain the patient routinelyDContinue diphenhydramineEDischarge without supervision

Reveal answer and rationale

✓Correct answer: B. Identify and treat underlying causes, stop contributing medications, provide orientation, hydration, mobility, and sleep support

Delirium management focuses on reversing causes and using multicomponent nonpharmacologic care. Medication is reserved for selected circumstances involving severe distress or immediate danger.

Q4

Which medication most likely contributed to urinary retention and confusion?

Reveal answer and rationale

✓Correct answer: A. Diphenhydramine

Diphenhydramine has significant anticholinergic activity and can contribute to confusion, dry mouth, constipation, blurred vision, and urinary retention, especially in older adults.

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Diagnosis: Hyperactive delirium caused by infection, urinary retention, dehydration, and anticholinergic exposure

Common causes

Infection
Medication effects
Electrolyte disorders

Hypoxia
Pain
Urinary retention
Constipation
Withdrawal
Stroke
Organ failure

Key assessments

Attention and level of consciousness
Medication review
Glucose
Oxygen saturation
CBC and electrolytes
Urinalysis when clinically indicated
Bladder scan
Assessment for pain and constipation

Treatment principles

Treat underlying causes
Discontinue unnecessary psychoactive or anticholinergic medication
Correct dehydration and sensory impairment
Promote daytime mobility
Provide familiar orientation cues
Reduce nighttime disruption

Clinical Pearl: Delirium may be the first manifestation of serious illness in an older adult.

NPLEX Trap: Do not diagnose dementia based on sudden confusion.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 38

Acute Compartment SyndromeClinical Case 38

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 27-year-old man presents after a tibial fracture was placed in a cast six hours ago. He reports rapidly increasing lower-leg pain despite opioid medication.

Physical examination:

Severe pain with passive extension of the toes
Tense, swollen anterior lower-leg compartment
Paresthesia over the foot
Palpable dorsalis pedis pulse

Q1

What is the most likely diagnosis?

ADeep-vein thrombosisBAcute compartment syndromeCSimple post-fracture painDCellulitisEChronic exertional compartment syndrome

Reveal answer and rationale

✓Correct answer: B. Acute compartment syndrome

Severe escalating pain, pain with passive stretch, a tense compartment, and sensory symptoms after fracture and casting indicate acute compartment syndrome.

Q2

What is the most appropriate immediate action?

AElevate the limb far above heart level and waitBRemove restrictive dressings, maintain the limb near heart level, and obtain immediate surgical assessmentCApply ice tightly around the castDPerform deep massageEEncourage weight-bearing

Reveal answer and rationale

✓Correct answer: B. Remove restrictive dressings, maintain the limb near heart level, and obtain immediate surgical assessment

External compression should be released immediately. Definitive treatment is urgent fasciotomy when compartment syndrome is diagnosed. Extreme elevation may further reduce arterial perfusion.

Q3

Which is typically the earliest and most sensitive clinical feature?

Reveal answer and rationale

✓Correct answer: B. Severe pain, especially with passive stretch

Pulselessness, paralysis, and pallor are late findings. Pulses may remain present because compartment pressure can impair tissue perfusion before occluding major arteries.

Q4

Which finding rules out compartment syndrome?

Reveal answer and rationale

✓Correct answer: C. Neither finding rules it out

Major arterial pulses and normal-appearing skin can persist despite dangerous intracompartmental pressure.

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Diagnosis: Acute compartment syndrome following tibial fracture and casting

Common causes

Long-bone fracture
Crush injury
Tight cast or dressing
Reperfusion injury
Hemorrhage
Burns
Intensive exercise

Key findings

Pain out of proportion
Pain with passive stretch
Tense compartment
Paresthesia
Progressive motor weakness

Treatment principles

Remove external compression
Keep limb near heart level
Immediate orthopedic consultation
Compartment-pressure measurement when diagnosis is uncertain
Emergency fasciotomy

Physical medicine: Massage, compression, heat, and exercise are contraindicated.

Clinical Pearl: A palpable pulse does not exclude compartment syndrome.

NPLEX Trap: Do not wait for all “six Ps” before acting.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 39

Exertional Heat StrokeClinical Case 39

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 21-year-old runner collapses near the end of a summer road race. Ambient temperature is 34°C with high humidity. Assessment:

Rectal temperature: 41.2°C
HR: 154/min
BP: 92/48 mmHg
Confused and combative
Skin is hot and wet
Unsteady before collapse

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Exertional heat stroke

Severe hyperthermia with central nervous system dysfunction defines heat stroke. Sweating may still be present in exertional heat stroke.

Q2

What is the most appropriate immediate treatment?

AGive oral fluids and observeBBegin immediate whole-body cooling, preferably cold-water immersion when feasible, while supporting airway, breathing, and circulationCAdminister acetaminophenDWrap the patient in blanketsEDelay cooling until hospital arrival

Reveal answer and rationale

✓Correct answer: B. Begin immediate whole-body cooling, preferably cold-water immersion when feasible, while supporting airway, breathing, and circulation

Rapid cooling is the priority. In exertional heat stroke, cooling should begin immediately and should not be delayed for transport when effective field cooling is available. The Wilderness Medical Society guideline emphasizes rapid recognition, prompt cooling, appropriate hydration, and avoidance of delays in reducing core temperature.

Q3

Which temperature measurement is most appropriate for suspected exertional heat stroke?

Reveal answer and rationale

✓Correct answer: B. Rectal core temperature

Rectal temperature is the most reliable practical core-temperature measurement during exertional heat illness. Oral, axillary, tympanic, or skin measurements may underestimate severity.

Q4

Why are acetaminophen and NSAIDs not appropriate treatments for heat stroke?

AHeat stroke results from failed heat dissipation rather than a raised hypothalamic fever set pointBThey always cause hypothermiaCThey immediately produce seizuresDThey prevent sweatingEThey increase blood glucose

Reveal answer and rationale

✓Correct answer: A. Heat stroke results from failed heat dissipation rather than a raised hypothalamic fever set point

Antipyretics treat fever mediated by a changed hypothalamic set point. They do not correct environmental or exertional hyperthermia and may create hepatic or renal risk.

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Diagnosis: Exertional heat stroke

Diagnostic features

Severe core hyperthermia
Altered mental status
Recent heat exposure or intense exertion

Potential complications

Rhabdomyolysis
Acute kidney injury
Liver injury
Coagulopathy
Seizures
Acute respiratory distress
Shock

Treatment principles

Immediate rapid cooling
Airway and cardiovascular support
Careful fluid and electrolyte management
Hospital evaluation
Monitoring for multiorgan injury

Clinical Pearl: Sweating does not exclude heat stroke.

NPLEX Trap: Do not delay cooling while arranging transportation.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 40

Severe Symptomatic HyponatremiaClinical Case 40

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 56-year-old woman with small-cell lung cancer presents with headache, confusion, vomiting, and a generalized seizure. Medications:

Sertraline
Hydrochlorothiazide Laboratory findings:
Sodium: 112 mmol/L
Serum osmolality: low
Urine osmolality: inappropriately elevated
Urine sodium: elevated
Glucose: normal She appears euvolemic.

Q1

What is the most likely diagnosis?

AHypernatremiaBSevere symptomatic hypotonic hyponatremia, likely due to SIADHCDiabetes insipidusDHyperosmolar hyperglycemic stateEPrimary hyperaldosteronism

Reveal answer and rationale

✓Correct answer: B. Severe symptomatic hypotonic hyponatremia, likely due to SIADH

Profound hypotonic hyponatremia with concentrated urine, elevated urine sodium, apparent euvolemia, and small-cell lung cancer strongly suggests SIADH. Hydrochlorothiazide and sertraline can also contribute.

Q2

What is the most appropriate immediate treatment?

ARapidly normalize sodium with unrestricted hypertonic salineBCarefully administered hypertonic saline with frequent sodium and neurologic monitoringCGive large amounts of free waterDUse oral salt only and dischargeEBegin desmopressin as the sole initial treatment

Reveal answer and rationale

✓Correct answer: B. Carefully administered hypertonic saline with frequent sodium and neurologic monitoring

Seizure and severe neurologic symptoms require urgent controlled sodium elevation using hypertonic saline. The goal is an initial small increase sufficient to reduce cerebral edema and stop severe symptoms, not immediate normalization.

Q3

What is the major danger of correcting chronic hyponatremia too rapidly?

ACerebral edema from persistent low sodiumBOsmotic demyelination syndromeCAcute hyperthyroidismDIron-deficiency anemiaERespiratory alkalosis

Reveal answer and rationale

✓Correct answer: B. Osmotic demyelination syndrome

Excessively rapid correction can cause severe neurologic injury, including dysarthria, dysphagia, quadriparesis, altered consciousness, and locked-in syndrome.

Q4

Which medication should be reviewed as a potential contributor?

Reveal answer and rationale

✓Correct answer: A. Hydrochlorothiazide

Thiazide diuretics are a common medication-related cause of hyponatremia. SSRIs can also contribute through SIADH.

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Diagnosis: Severe symptomatic hypotonic hyponatremia caused by SIADH and medication effects

Potential causes of SIADH

Small-cell lung cancer
CNS disease
Pulmonary disease
Pain and nausea
SSRIs
Carbamazepine
Certain chemotherapies

Key investigations

Serum sodium
Serum osmolality
Urine osmolality
Urine sodium
Glucose
Renal function
Thyroid assessment
Morning cortisol
Medication review

Treatment principles

Hypertonic saline for seizures or severe neurologic symptoms
Frequent sodium monitoring
Avoid overly rapid correction
Stop contributing medications
Treat the underlying cause
Fluid restriction or other SIADH treatment after stabilization

Clinical Pearl: The severity of neurologic symptoms depends partly on how rapidly sodium decreased, not only the absolute value.

NPLEX Trap: Do not rapidly normalize sodium to the reference range.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 41

Acute Mesenteric IschemiaClinical Case 41

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 76-year-old woman presents with sudden, severe central abdominal pain that began two hours ago. Medical history:

Atrial fibrillation
Hypertension
Peripheral arterial disease She stopped taking her anticoagulant three weeks ago because of bruising. Vital signs:
BP: 104/66 mmHg
HR: 124/min and irregular
RR: 24/min
Temperature: 37.5°C Physical examination:
Appears distressed
Abdomen is soft
Mild diffuse tenderness
No guarding or rebound tenderness Laboratory findings:
WBC: 16.8 × 10⁹/L
Lactate: 3.8 mmol/L
Bicarbonate: 18 mmol/L

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute mesenteric ischemia

Sudden severe abdominal pain that is disproportionate to the initial physical findings is characteristic of acute mesenteric ischemia. Atrial fibrillation and interruption of anticoagulation strongly suggest an arterial embolus. Why the Other Options Are Incorrect

A. Irritable bowel syndrome: Does not usually produce sudden severe pain, metabolic acidosis, or elevated lactate.
C. Gastroenteritis: Usually causes diarrhea or vomiting and more generalized gastrointestinal symptoms.
D. Cystitis: Does not explain severe abdominal pain or metabolic abnormalities.
E. Constipation: Does not generally present with sudden pain out of proportion to the examination.

Q2

What is the most appropriate next diagnostic study?

ACT angiography of the abdomen and pelvisBRoutine abdominal radiograph onlyCColonoscopyDUpper gastrointestinal endoscopyEOutpatient abdominal ultrasound next week

Reveal answer and rationale

✓Correct answer: A. CT angiography of the abdomen and pelvis

Urgent CT angiography evaluates the mesenteric vessels and bowel for arterial occlusion, ischemia, infarction, and alternative diagnoses.

Q3

What is the most appropriate initial management?

AAdminister a stimulant laxativeBBegin emergency resuscitation, intravenous anticoagulation when appropriate, antibiotics, and urgent vascular or surgical consultationCRecommend a high-fibre mealDBegin abdominal massageEObserve at home for six hours

Reveal answer and rationale

✓Correct answer: B. Begin emergency resuscitation, intravenous anticoagulation when appropriate, antibiotics, and urgent vascular or surgical consultation

Acute mesenteric ischemia is a time-sensitive vascular emergency. Management focuses on restoring perfusion before irreversible bowel necrosis occurs. Current vascular guidance emphasizes urgent diagnosis, early antibiotics, revascularization, and surgery when bowel infarction or peritonitis is present.

Q4

Which finding most strongly suggests progression to bowel infarction?

AMild intermittent nauseaBPeritoneal rigidity, worsening acidosis, and hemodynamic instabilityCSoft abdomenDHistory of atrial fibrillationEMild leukocytosis

Reveal answer and rationale

✓Correct answer: B. Peritoneal rigidity, worsening acidosis, and hemodynamic instability

Guarding, rebound tenderness, shock, rising lactate, and worsening acidosis suggest transmural bowel infarction or perforation and require immediate surgery.

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Diagnosis: Acute embolic mesenteric ischemia

Major causes

Arterial embolism from atrial fibrillation
Arterial thrombosis
Mesenteric venous thrombosis
Nonocclusive mesenteric ischemia
Aortic dissection

Key investigations

CT angiography
CBC
Electrolytes
Renal function
Lactate and blood gas
Coagulation studies
ECG
Blood type and crossmatch

Treatment principles

Emergency stabilization
Fasting
Intravenous fluids
Broad antimicrobial therapy
Anticoagulation when appropriate
Urgent revascularization
Resection of nonviable bowel

Botanical and physical medicine safety: Laxatives, abdominal massage, castor-oil packs, and oral botanical treatment are contraindicated when bowel ischemia is suspected.

Clinical Pearl: Severe pain can precede major abdominal examination findings.

NPLEX Trap: A normal or mildly tender abdomen does not exclude early mesenteric ischemia.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 42

Severe Hypercalcemia of MalignancyClinical Case 42

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 67-year-old man with metastatic squamous-cell lung cancer presents with progressive confusion, constipation, nausea, excessive thirst, and generalized weakness. Vital signs:

BP: 104/64 mmHg
HR: 112/min
RR: 18/min Physical examination:
Dry mucous membranes
Reduced deep-tendon reflexes
Confused and lethargic Laboratory findings:
Corrected calcium: 3.72 mmol/L
Creatinine: 182 µmol/L
Phosphate: low
PTH: suppressed ECG demonstrates a shortened QT interval.

Q1

What is the most likely diagnosis?

AHypocalcemiaBSevere hypercalcemia of malignancyCPrimary hypothyroidismDHyperkalemiaESyndrome of inappropriate antidiuretic hormone secretion

Reveal answer and rationale

✓Correct answer: B. Severe hypercalcemia of malignancy

Markedly elevated calcium with dehydration, altered mental status, gastrointestinal symptoms, weakness, kidney dysfunction, shortened QT interval, and suppressed PTH indicates severe non-PTH-mediated hypercalcemia.

Q2

What is the most appropriate initial treatment?

AFluid restrictionBIntravenous isotonic saline after cardiovascular assessmentCOral calcium supplementationDHydrochlorothiazideEVitamin D supplementation

Reveal answer and rationale

✓Correct answer: B. Intravenous isotonic saline after cardiovascular assessment

Severe hypercalcemia commonly causes significant volume depletion. Initial treatment generally includes isotonic fluid replacement, with careful monitoring in patients with heart or kidney disease.

Q3

Which medication provides a relatively rapid but temporary reduction in serum calcium?

Reveal answer and rationale

✓Correct answer: A. Calcitonin

Calcitonin can lower calcium relatively quickly, but tachyphylaxis limits its duration of effectiveness. It is generally used as a short-term bridge while a longer-acting antiresorptive agent takes effect.

Q4

Which longer-acting treatment is recommended for hypercalcemia of malignancy?

AAn intravenous bisphosphonate or denosumabBOral calcium carbonateCA thiazide diureticDHigh-dose vitamin AEPotassium chloride

Reveal answer and rationale

✓Correct answer: A. An intravenous bisphosphonate or denosumab

The Endocrine Society recommends an intravenous bisphosphonate or denosumab for adults with hypercalcemia of malignancy. Calcitonin may be added temporarily in severe cases.

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Diagnosis: Severe hypercalcemia of malignancy

Common causes of hypercalcemia

Primary hyperparathyroidism
Humoral hypercalcemia of malignancy

Osteolytic metastases
Multiple myeloma
Excess vitamin D
Granulomatous disease
Thiazide use
Lithium
Immobilization

Key investigations

Corrected or ionized calcium
PTH
Phosphate
Magnesium
Creatinine
ECG
PTH-related peptide when indicated
Vitamin D metabolites
Malignancy assessment

Treatment principles

Intravenous isotonic fluid
Calcitonin for rapid temporary control
Bisphosphonate or denosumab
Treatment of the malignancy
Dialysis in selected refractory cases with severe kidney or cardiac limitations

Nutrition and supplement safety: Stop unnecessary calcium, vitamin D, vitamin A, and products that may contribute to hypercalcemia.

Clinical Pearl: Hypercalcemia can cause nephrogenic diabetes insipidus, leading to polyuria and worsening dehydration.

NPLEX Trap: Do not routinely use a thiazide diuretic because it can reduce urinary calcium excretion and worsen hypercalcemia.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 43

Severe Alcohol Withdrawal with DeliriumClinical Case 43

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 54-year-old man is admitted after falling and fracturing his wrist. Approximately 72 hours after his last alcoholic drink, he becomes extremely agitated and confused. He normally drinks approximately 12 alcoholic beverages daily. Vital signs:

BP: 184/106 mmHg
HR: 136/min
RR: 24/min
Temperature: 38.3°C Physical examination:
Profuse sweating
Coarse tremor
Visual hallucinations
Disorientation
Severe agitation
No focal neurologic deficit

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Alcohol-withdrawal delirium

Severe agitation, hallucinations, confusion, autonomic hyperactivity, and tremor developing several days after alcohol cessation are consistent with alcohol-withdrawal delirium, also called delirium tremens.

Q2

What is the first-line medication class?

Reveal answer and rationale

✓Correct answer: A. Benzodiazepines

Benzodiazepines are first-line treatment for moderate to severe alcohol withdrawal and help prevent withdrawal seizures and progression of autonomic instability.

Q3

Which vitamin should be administered because deficiency can cause Wernicke encephalopathy?

Reveal answer and rationale

✓Correct answer: A. Thiamine

Chronic alcohol use is associated with thiamine deficiency. Parenteral thiamine should be given promptly when Wernicke encephalopathy is possible.

Glucose should not be withheld in hypoglycemia, but thiamine should be administered before or alongside glucose whenever feasible.

Q4

Which finding would require evaluation for a cause other than uncomplicated withdrawal?

Reveal answer and rationale

✓Correct answer: B. Focal neurologic deficit

Focal deficits raise concern for stroke, intracranial hemorrhage, traumatic injury, infection, or another neurologic disorder and are not explained by uncomplicated withdrawal.

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Diagnosis: Severe complicated alcohol withdrawal with delirium

Typical progression

Tremor and anxiety
Insomnia
Nausea
Hallucinations
Withdrawal seizures
Delirium with autonomic instability

Key assessments

Airway and vital signs
Glucose
Electrolytes

Magnesium and phosphate
Liver function
CBC
Toxicology assessment
Trauma evaluation
Infection screening
Thiamine-deficiency assessment

Treatment principles

Monitored hospital treatment
Benzodiazepines
Thiamine
Fluid and electrolyte correction
Treatment of trauma or infection
Seizure precautions
Long-term alcohol-use-disorder treatment after stabilization

Botanical safety: Sedating herbs should not replace benzodiazepines or monitored emergency treatment.

Clinical Pearl: A patient can have alcohol withdrawal and another serious condition simultaneously.

NPLEX Trap: Antipsychotics may be adjuncts in selected cases but should not replace adequate benzodiazepine treatment.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 44

Acetaminophen Toxicity with Acute Liver FailureClinical Case 44

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 29-year-old woman presents with nausea, vomiting, right-upper-quadrant pain, and increasing confusion. She reports taking “a large amount” of acetaminophen-containing tablets approximately 18 hours ago. Laboratory findings:

AST: 6,800 U/L
ALT: 7,200 U/L
INR: 3.6
Bilirubin: mildly elevated
Glucose: 3.1 mmol/L
Lactate: elevated
Creatinine: elevated
Acetaminophen level: detectable

Q1

What is the most likely diagnosis?

AAcute acetaminophen-induced liver failureBChronic uncomplicated hepatitisCAcute cholecystitisDAlcohol withdrawalEHemolytic anemia

Reveal answer and rationale

✓Correct answer: A. Acute acetaminophen-induced liver failure

A history of overdose, extremely high aminotransferases, coagulopathy, hypoglycemia, kidney injury, and encephalopathy strongly indicate acetaminophen-related acute liver failure.

Q2

What is the antidote?

Reveal answer and rationale

✓Correct answer: A. N-acetylcysteine

N-acetylcysteine replenishes glutathione and reduces toxic acetaminophen metabolites. It should be started promptly when toxicity is suspected and is beneficial even when presentation is delayed. North American toxicology organizations published a consensus guideline supporting prompt risk assessment and acetylcysteine treatment.

Q3

Which tool is used for a single acute ingestion with a reliable known time?

ARumack–Matthew nomogram using the level obtained at least four hours after ingestionBWells scoreCCHA₂DS₂-VASc scoreDGlasgow coma score aloneESerum bilirubin alone

Reveal answer and rationale

✓Correct answer: A. Rumack–Matthew nomogram using the level obtained at least four hours after ingestion

The nomogram estimates toxicity risk following a single acute ingestion when the timing is reliable. It should not be used in repeated supratherapeutic ingestion, unknown-time ingestion, or presentations occurring outside its validated time range.

Q4

What is the most appropriate disposition?

ADischarge once vomiting improvesBIntensive monitoring and urgent consultation with a poison centre and liver-transplant centreCOutpatient repeat liver enzymes in one weekDBegin milk thistle as sole therapyERecommend a liver-detoxification diet

Reveal answer and rationale

✓Correct answer: B. Intensive monitoring and urgent consultation with a poison centre and liver-transplant centre

Acute liver failure with encephalopathy and coagulopathy requires critical-care management and early transplant-centre involvement. AASLD guidance emphasizes identifying acetaminophen toxicity and rapidly assessing patients with acute liver failure.

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Diagnosis: Acetaminophen-induced acute liver failure

Clinical stages may include

Early nausea and vomiting
Right-upper-quadrant pain
Rapid aminotransferase elevation
Coagulopathy
Hypoglycemia
Encephalopathy
Kidney injury
Multiorgan failure

Key investigations

Acetaminophen concentration
AST and ALT
INR
Bilirubin
Glucose
Creatinine
Electrolytes
Lactate and blood gas
Toxicology and co-ingestion assessment

Treatment principles

Immediate N-acetylcysteine
Poison-centre consultation
Glucose correction
Management of cerebral edema and organ failure
Early transplant-centre referral
Psychiatric assessment after stabilization when the ingestion was intentional

Botanical medicine: Milk thistle or other liver products must not replace N-acetylcysteine.

Clinical Pearl: The patient may appear relatively well during the early phase despite evolving hepatotoxicity.

NPLEX Trap: Do not delay N-acetylcysteine while waiting for every laboratory result when significant toxicity is suspected.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 45

Spinal Epidural AbscessClinical Case 45

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 58-year-old man presents with worsening thoracic back pain, fever, and leg weakness. Medical history:

Type 2 diabetes
Injection-drug use
Recent skin abscess Vital signs:
BP: 108/68 mmHg
HR: 118/min
Temperature: 39.1°C Physical examination:
Severe midline thoracic tenderness
Bilateral leg weakness
Reduced sensation below the umbilicus
Difficulty urinating
Brisk lower-extremity reflexes

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Spinal epidural abscess

Back pain, fever, neurologic deficits, urinary dysfunction, diabetes, injection-drug use, and recent infection strongly suggest spinal epidural abscess with cord compression. The complete classic triad may not be present early, so a high index of suspicion is required.

Q2

What is the most appropriate diagnostic study?

AUrgent contrast-enhanced MRI of the spineBRoutine spinal radiographCBone-density scanDElectromyography before imagingEOutpatient CT in one month

Reveal answer and rationale

✓Correct answer: A. Urgent contrast-enhanced MRI of the spine

MRI with contrast is the preferred investigation for detecting an epidural collection, vertebral infection, discitis, and spinal-cord compression. Imaging of the entire spine may be appropriate when symptoms or infection patterns suggest multiple sites.

Q3

What is the most appropriate treatment?

ASpinal manipulation and massageBUrgent intravenous antibiotics and neurosurgical or spinal surgical assessmentCOral analgesia and dischargeDEpidural corticosteroid injectionETraction therapy

Reveal answer and rationale

✓Correct answer: B. Urgent intravenous antibiotics and neurosurgical or spinal surgical assessment

Neurologic deficits indicate a spinal emergency. Treatment commonly includes antimicrobial therapy and surgical decompression or drainage when neurologic compromise, instability, or significant compression is present.

Q4

Which procedure is contraindicated?

Reveal answer and rationale

✓Correct answer: C. Spinal manipulation

Manipulation could worsen cord compression and dangerously delay definitive diagnosis and treatment.

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Diagnosis: Thoracic spinal epidural abscess with spinal-cord compression

Risk factors

Diabetes
Injection-drug use
Recent bacteremia
Skin infection
Spinal procedure
Immunosuppression
Hemodialysis
Vertebral osteomyelitis

Key investigations

Contrast-enhanced MRI
Blood cultures
CBC
ESR and CRP
Renal and liver function
Culture of drained material

Treatment principles

Immediate hospital admission
Intravenous antimicrobial therapy
Urgent spinal-surgery consultation
Decompression or drainage when indicated
Treatment of the original infection source

Physical medicine: Manipulation, traction, electrical therapy, massage, and exercise are contraindicated during the acute presentation.

Clinical Pearl: Fever may be absent, especially in older or immunocompromised patients.

NPLEX Trap: Do not diagnose mechanical back pain when neurologic deficits, fever, or infection risk factors are present.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 46

Postpartum Hemorrhage Due to Uterine AtonyClinical Case 46

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 33-year-old woman develops heavy vaginal bleeding immediately after an uncomplicated vaginal delivery. Assessment:

Estimated blood loss is rapidly increasing
BP: 82/46 mmHg
HR: 132/min
Skin is pale and clammy
Uterus is enlarged, soft, and poorly contracted
Placenta appears complete
No obvious large genital-tract laceration is seen

Q1

What is the most likely cause of the hemorrhage?

Reveal answer and rationale

✓Correct answer: A. Uterine atony

A soft, enlarged, poorly contracted uterus with heavy postpartum bleeding strongly indicates uterine atony, the most common cause of postpartum hemorrhage.

Q2

What is the most appropriate immediate action?

AObserve for 30 minutesBActivate the postpartum-hemorrhage protocol, perform uterine massage, administer a uterotonic, and begin resuscitationCGive an oral iron tabletDRecommend breastfeeding only and reassessEAdminister an herbal uterine tonic

Reveal answer and rationale

✓Correct answer: B. Activate the postpartum-hemorrhage protocol, perform uterine massage, administer a uterotonic, and begin resuscitation

Management is simultaneous: call for help, support circulation, quantify blood loss, identify the cause, massage an atonic uterus, administer uterotonic medication, and prepare blood products or procedures when needed. ACOG supports standardized emergency protocols for postpartum hemorrhage.

Q3

Which medication is generally first-line for uterine atony?

Reveal answer and rationale

✓Correct answer: A. Oxytocin

Oxytocin promotes uterine contraction and is generally the first-line uterotonic for prevention and treatment of uterine atony.

Q4

Which uterotonic requires particular caution or avoidance in a patient with severe hypertension?

Reveal answer and rationale

✓Correct answer: A. Methylergonovine

Methylergonovine can produce significant vasoconstriction and hypertension and is generally avoided in patients with hypertension or preeclampsia.

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Diagnosis: Primary postpartum hemorrhage caused by uterine atony

The four Ts

Tone: Uterine atony
Trauma: Laceration, hematoma, rupture
Tissue: Retained placenta or placental tissue
Thrombin: Coagulopathy

Key assessments

Hemodynamic status
Quantified blood loss
Uterine tone
Placental completeness
Genital-tract inspection
CBC
Coagulation studies
Fibrinogen

Type and crossmatch

Treatment principles

Call for help
Uterine massage
Uterotonic medication
Intravenous access and fluid resuscitation
Blood products when required
Tranexamic acid when clinically indicated
Balloon tamponade, surgery, or hysterectomy if bleeding persists

Botanical safety: Herbal uterotonics are inappropriate during acute hemorrhagic shock.

Clinical Pearl: Blood-pressure reduction can occur late in obstetric hemorrhage; tachycardia and increasing blood loss require early action.

NPLEX Trap: Do not treat significant postpartum blood loss with oral iron alone.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 47

Infective EndocarditisClinical Case 47

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 42-year-old man presents with three weeks of fever, fatigue, night sweats, and weight loss. Medical history:

Injection-drug use
Previous skin abscesses Vital signs:
BP: 112/66 mmHg
HR: 110/min
Temperature: 38.8°C Physical examination:
New systolic murmur
Splinter hemorrhages
Tender fingertip nodules
Multiple small injection-site infections

Laboratory findings:

WBC: elevated
ESR and CRP: elevated
Microscopic hematuria

Q1

What is the most likely diagnosis?

AInfective endocarditisBAcute rheumatic fever onlyCViral upper-respiratory infectionDStable valvular heart diseaseEPanic disorder

Reveal answer and rationale

✓Correct answer: A. Infective endocarditis

Prolonged fever, a new murmur, injection-drug use, vascular or immunologic skin findings, and hematuria strongly suggest infective endocarditis. Tender fingertip nodules are consistent with Osler nodes.

Q2

What should be obtained before antibiotics when this can be done without causing dangerous delay?

AMultiple sets of blood cultures from separate venipuncture sitesBStool cultureCSputum cytologyDSkin-prick allergy testingESerum vitamin D

Reveal answer and rationale

✓Correct answer: A. Multiple sets of blood cultures from separate venipuncture sites

Multiple blood cultures help identify the organism and guide therapy. In unstable patients, cultures should be obtained promptly without delaying lifesaving antimicrobial treatment.

Q3

Which imaging study is usually performed first?

Reveal answer and rationale

✓Correct answer: A. Transthoracic echocardiography

Transthoracic echocardiography is generally the initial cardiac imaging test. Transesophageal echocardiography is more sensitive and is indicated when initial imaging is negative but suspicion remains high, prosthetic material is present, or complications are suspected.

Q4

What is the appropriate treatment approach?

AProlonged organism-directed intravenous antimicrobial therapy, with surgical assessment when indicatedBOral botanical antimicrobials aloneCAspirin onlyDRoutine corticosteroid therapyEDelay treatment until all embolic complications develop

Reveal answer and rationale

✓Correct answer: A. Prolonged organism-directed intravenous antimicrobial therapy, with surgical assessment when indicated

Endocarditis requires multidisciplinary management. Surgery may be required for heart failure, uncontrolled infection, abscess, prosthetic-valve complications, or high embolic risk. The 2023 ESC guideline emphasizes blood cultures, multimodality imaging, antimicrobial therapy, and coordinated endocarditis-team care.

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Diagnosis: Probable infective endocarditis

Common organisms and settings

Staphylococcus aureus
Viridans streptococci
Enterococci
Prosthetic-valve organisms
Injection-associated bloodstream infection

Potential complications

Heart failure
Valve destruction
Septic emboli
Stroke
Splenic or renal infarction
Abscess
Conduction abnormalities
Immune-complex glomerulonephritis

Key investigations

Multiple blood cultures
Transthoracic echocardiography
Transesophageal echocardiography
CBC
Renal function
ESR and CRP
Urinalysis
ECG

Imaging for embolic complications

Treatment principles

Hospital admission
Organism-directed antimicrobial therapy
Source control
Surgical assessment when indicated
Addiction care and harm-reduction support when relevant

Botanical safety: Botanical antimicrobials do not provide adequate treatment for infection of cardiac valves.

Clinical Pearl: Blood cultures may become negative after previous antibiotic exposure.

NPLEX Trap: A negative transthoracic echocardiogram does not exclude endocarditis when clinical suspicion remains high.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 48

Giant Cell ArteritisClinical Case 48

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 72-year-old woman presents with a new left-sided headache, scalp tenderness, fatigue, and pain in her jaw when chewing. She also reports two brief episodes of vision loss in her left eye. Physical examination:

Left temporal artery is tender and reduced in pulsation
Visual acuity is mildly reduced
Proximal shoulder stiffness is present Laboratory findings:
ESR: 92 mm/hour
CRP: markedly elevated
Platelets: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Giant cell arteritis

A new headache in a patient older than 50, scalp tenderness, jaw claudication, transient visual loss, temporal-artery abnormality, and elevated inflammatory markers strongly indicate giant cell arteritis.

Q2

What is the most appropriate immediate action?

AWait for biopsy confirmation before treatmentBBegin high-dose glucocorticoid treatment immediately and arrange urgent specialist assessmentCPrescribe a triptanDPerform cervical manipulationERecommend massage and reassessment in one week

Reveal answer and rationale

✓Correct answer: B. Begin high-dose glucocorticoid treatment immediately and arrange urgent specialist assessment

Treatment should begin immediately when giant cell arteritis is strongly suspected because delay can cause irreversible visual loss. ACR patient guidance and management recommendations emphasize prompt glucocorticoid treatment.

Q3

Which diagnostic procedure can support the diagnosis?

Reveal answer and rationale

✓Correct answer: A. Temporal-artery biopsy

Temporal-artery biopsy may demonstrate granulomatous inflammation and giant cells. Ultrasound and other vascular imaging are increasingly used depending on local expertise. A negative biopsy does not completely exclude the disease because inflammation can be segmental.

Q4

Which associated condition is suggested by the patient’s shoulder stiffness?

Reveal answer and rationale

✓Correct answer: A. Polymyalgia rheumatica

Polymyalgia rheumatica frequently overlaps with giant cell arteritis and causes bilateral shoulder or hip-girdle pain and morning stiffness.

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Diagnosis: Giant cell arteritis with threatened visual ischemia

High-yield features

Age 50 years or older
New headache
Scalp tenderness
Jaw or tongue claudication
Visual disturbance
Constitutional symptoms
Elevated ESR and CRP
Polymyalgia rheumatica symptoms

Key investigations

ESR and CRP
CBC and platelets
Temporal-artery ultrasound
Temporal-artery biopsy
Large-vessel imaging when indicated
Immediate ophthalmologic assessment for visual symptoms

Treatment principles

Immediate high-dose glucocorticoids
Intravenous glucocorticoids in selected patients with threatened or established visual loss
Steroid-sparing therapy such as tocilizumab in appropriate patients
Bone and infection-risk prevention during prolonged therapy
Monitoring for aortic disease

Physical medicine: Cervical manipulation or massage must not delay emergency treatment.

Clinical Pearl: Normal inflammatory markers make GCA less likely but do not absolutely exclude it.

NPLEX Trap: Do not delay glucocorticoids while waiting for biopsy.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 49

Diabetic Foot Infection with OsteomyelitisClinical Case 49

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 64-year-old man with poorly controlled type 2 diabetes presents with a worsening plantar-foot ulcer. History:

Peripheral neuropathy
Peripheral arterial disease
Previous toe amputation Vital signs:
BP: 96/58 mmHg
HR: 120/min
Temperature: 39.0°C Physical examination:
Deep plantar ulcer with purulent drainage
Surrounding erythema extending to the ankle
Foul odour
Bone is palpable with a sterile probe
Reduced pedal pulses
Reduced protective sensation Laboratory findings:
WBC: 18.4 × 10⁹/L
CRP: markedly elevated
Glucose: 19 mmol/L
Creatinine: elevated

Q1

What is the most likely diagnosis?

AUncomplicated superficial foot ulcerBSevere diabetic foot infection with probable osteomyelitis and sepsisCGoutDPlantar fasciitisEContact dermatitis

Reveal answer and rationale

✓Correct answer: B. Severe diabetic foot infection with probable osteomyelitis and sepsis

Systemic instability, extensive cellulitis, purulent drainage, a deep ulcer, and palpable bone suggest severe infection with underlying osteomyelitis.

Q2

What is the most appropriate management?

ATopical tea-tree oil and outpatient follow-upBUrgent hospitalization, intravenous antibiotics, surgical assessment, vascular evaluation, and glucose managementCApply an occlusive dressing and continue walking normallyDBegin oral glucosamineEPerform aggressive foot massage

Reveal answer and rationale

✓Correct answer: B. Urgent hospitalization, intravenous antibiotics, surgical assessment, vascular evaluation, and glucose management

Severe infection with systemic illness requires emergency care. Treatment includes antimicrobials, drainage or debridement, vascular assessment, off-loading, glucose management, and evaluation of bone infection.

Q3

Which finding increases suspicion for osteomyelitis?

Reveal answer and rationale

✓Correct answer: A. A positive probe-to-bone test

Palpating hard or gritty bone through a diabetic foot ulcer increases the likelihood of osteomyelitis, particularly when the ulcer is deep or chronic. MRI is generally the most sensitive imaging study when the diagnosis remains uncertain.

Q4

Which long-term intervention is essential for preventing recurrence?

ADaily foot inspection, protective footwear, pressure off-loading, glucose control, and regular podiatric careBWalking barefoot to strengthen the feetCHeating pads on numb feetDRoutine foot soaking in very hot waterECutting calluses with a razor at home

Reveal answer and rationale

✓Correct answer: A. Daily foot inspection, protective footwear, pressure off-loading, glucose control, and regular podiatric care

Neuropathy reduces protective sensation, while ischemia impairs healing. Prevention requires foot surveillance, appropriate footwear, pressure reduction, vascular care, and metabolic risk management.

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Diagnosis: Severe diabetic foot infection with probable osteomyelitis

Major risk factors

Peripheral neuropathy
Peripheral arterial disease
Poor glucose control
Previous ulcer or amputation
Foot deformity
Inappropriate footwear
Kidney disease

Key investigations

CBC and inflammatory markers
Blood cultures in systemic illness
Deep-tissue culture after cleaning or debridement
Plain radiograph
MRI when osteomyelitis remains uncertain
Vascular assessment
Renal function and glucose

Treatment principles

Hospital care for severe infection
Appropriate antimicrobials
Surgical drainage or debridement
Pressure off-loading
Revascularization when indicated
Glucose management
Wound-care follow-up

Botanical and physical medicine safety: Do not place irritating botanical products into a deep infected ulcer. Heat, massage, and weight-bearing exercise may worsen injury.

Clinical Pearl: Pain may be minimal despite severe infection because of neuropathy.

NPLEX Trap: Absence of pain does not indicate a mild diabetic foot infection.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 50

Major Depressive Episode with Imminent Suicide RiskClinical Case 50

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 37-year-old woman presents with eight weeks of depressed mood, loss of interest, insomnia, guilt, low energy, poor concentration, and reduced appetite. She recently lost her job and separated from her partner. When asked directly about safety, she states: “I bought a bottle of sleeping pills. I plan to take them tonight after my children go to their father’s house.” She reports consuming alcohol daily and has stopped answering calls from family members.

Q1

What is the most likely diagnosis?

AMajor depressive episode with imminent suicide riskBNormal sadness onlyCGeneralized anxiety disorder onlyDAdjustment disorder without safety concernEBipolar mania

Reveal answer and rationale

✓Correct answer: A. Major depressive episode with imminent suicide risk

The patient has persistent depressive symptoms with impaired functioning and a specific suicide plan, access to the intended method, and stated timing. These findings indicate imminent risk requiring immediate intervention.

Q2

What is the most appropriate next step?

AAsk her to promise not to harm herself and send her homeBMaintain continuous supervision, remove access to lethal means when safely possible, and arrange emergency psychiatric assessmentCSchedule routine counseling in two weeksDRecommend St. John’s wortEEncourage her to sleep and reassess tomorrow

Reveal answer and rationale

✓Correct answer: B. Maintain continuous supervision, remove access to lethal means when safely possible, and arrange emergency psychiatric assessment

A specific plan, accessible means, intent, and near-term timing require immediate emergency assessment. The patient should not be left alone.

Q3

Which approach is most appropriate when asking about suicide?

AAvoid direct questions because they may introduce the ideaBAsk directly about thoughts, plan, intent, access to means, past attempts, substance use, and protective factorsCAsk only whether the patient feels sadDSpeak only with family and not with the patientEUse a screening questionnaire as the sole assessment

Reveal answer and rationale

✓Correct answer: B. Ask directly about thoughts, plan, intent, access to means, past attempts, substance use, and protective factors

Direct, calm, nonjudgmental questioning does not create suicidal thoughts. Screening tools can support—but do not replace—a comprehensive clinical risk assessment.

Q4

Which recommendation is inappropriate during the acute crisis?

AEmergency psychiatric assessmentBInvolving supportive people when appropriate and safeCInitiating St. John’s wort as the only intervention and delaying emergency careDRestricting access to medications and other lethal meansEAssessing alcohol and substance use

Reveal answer and rationale

✓Correct answer: C. Initiating St. John’s wort as the only intervention and delaying emergency care

No supplement, antidepressant prescription, or routine counseling appointment can substitute for immediate safety management when a patient has an imminent suicide plan. St. John’s wort also has major drug-interaction risks and may be inappropriate in bipolar-spectrum disorders or alongside serotonergic medications.

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Diagnosis: Major depressive episode with imminent suicide risk

High-risk features

Current intent
Specific plan
Access to lethal means
Near-term timing
Previous attempt
Substance intoxication
Agitation or severe insomnia
Psychosis
Recent major loss
Social isolation
Hopelessness

Protective factors may include

Supportive relationships
Responsibility to dependants
Religious or personal beliefs

Engagement in treatment
Future-oriented goals
Restricted access to lethal means

Immediate management principles

Do not leave the patient alone
Arrange emergency assessment
Reduce access to lethal means
Treat intoxication or withdrawal
Involve supports when clinically appropriate
Document the assessment and actions carefully
Develop a structured safety plan after immediate danger is addressed

Psychology: Use empathic, direct, nonjudgmental communication.

Botanical and pharmacologic safety: Avoid relying on supplements or newly initiated medication to control imminent risk. Antidepressants require follow-up and do not provide immediate protection during an acute suicidal crisis.

Clinical Pearl: Asking directly about suicide does not increase suicidal behaviour.

NPLEX Trap: A “no-suicide contract” does not replace risk assessment, supervision, safety planning, or emergency intervention.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 51

Acute Exacerbation of COPDClinical Case 51

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 69-year-old man with severe chronic obstructive pulmonary disease presents with three days of worsening shortness of breath, increased cough, and increased sputum production. His sputum has changed from clear to yellow-green. Medical history:

COPD
Hypertension
Tobacco use: 50 pack-years
Two COPD hospitalizations during the previous year Medications:
Tiotropium
Budesonide/formoterol
Salbutamol as needed Vital signs:
BP: 146/84 mmHg
HR: 112/min
RR: 30/min
Temperature: 38.1°C
SpO₂: 82% on room air Physical examination:
Speaks in short sentences
Uses accessory respiratory muscles
Diffuse wheezing
Reduced bilateral air entry
No unilateral leg swelling Arterial blood gas after controlled oxygen:
pH: 7.27
PaCO₂: 68 mmHg
PaO₂: 58 mmHg
Bicarbonate: 30 mmol/L

Q1

What is the most likely diagnosis?

AStable COPDBAcute COPD exacerbation with acute-on-chronic hypercapnic respiratory failureCAcute pulmonary embolism confirmed by examinationDPanic disorderEIsolated bacterial sinusitis

Reveal answer and rationale

✓Correct answer: B. Acute COPD exacerbation with acute-on-chronic hypercapnic respiratory failure

The patient has an acute worsening of dyspnea, cough, and sputum production accompanied by hypoxemia, respiratory acidosis, and carbon-dioxide retention. The elevated bicarbonate suggests chronic CO₂ retention, while the low pH indicates an acute decompensation.

Q2

What oxygen-saturation target is generally appropriate while blood gases are monitored?

Reveal answer and rationale

✓Correct answer: B. Approximately 88–92%

Controlled oxygen is generally used in COPD patients at risk of hypercapnic respiratory failure. Excessive oxygen administration may worsen carbon-dioxide retention in susceptible patients. Oxygen must not be withheld from a hypoxemic patient; it should be carefully titrated and reassessed with blood gases.

Q3

Which treatment combination is most appropriate?

AShort-acting inhaled bronchodilators, systemic corticosteroid, and antibiotics when bacterial features are presentBLong-acting beta₂-agonist monotherapy onlyCCough suppressant and dischargeDBotanical expectorants onlyEHigh-flow uncontrolled oxygen without reassessment

Reveal answer and rationale

✓Correct answer: A. Short-acting inhaled bronchodilators, systemic corticosteroid, and antibiotics when bacterial features are present

Initial treatment commonly includes short-acting bronchodilation and a short course of systemic corticosteroid. Antibiotics are considered when bacterial infection is suggested by purulent sputum, increased sputum volume, increased dyspnea, or a need for ventilatory support. The 2026 GOLD report defines COPD exacerbation as worsening dyspnea and/or cough and sputum over fewer than 14 days and provides current assessment and management recommendations.

Q4

Which finding most strongly supports noninvasive ventilation?

AMild cough with normal blood gasesBRespiratory acidosis with increased work of breathingCStable oxygen saturation without distressDChronic sputum production onlyENormal respiratory rate

Reveal answer and rationale

✓Correct answer: B. Respiratory acidosis with increased work of breathing

Noninvasive ventilation is strongly considered when a COPD exacerbation causes acute or acute-on-chronic respiratory acidosis and significant respiratory distress, provided there is no immediate indication for intubation. Contraindications or Failure Features

Inability to protect the airway
Severe facial trauma
Respiratory arrest
Hemodynamic instability
Severe agitation or inability to cooperate
Worsening gas exchange despite treatment

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Diagnosis: Acute COPD exacerbation with hypercapnic respiratory failure

Common triggers

Viral respiratory infection
Bacterial respiratory infection
Air pollution
Medication interruption
Heart failure
Pulmonary embolism
Pneumothorax

Key investigations

Oxygen saturation
Arterial or venous blood gas
Chest radiograph
ECG
CBC
Electrolytes and renal function
Viral testing when appropriate
Sputum testing in selected severe cases

Treatment principles

Controlled oxygen
Short-acting bronchodilators
Systemic corticosteroid
Antibiotics when indicated
Noninvasive ventilation for appropriate respiratory failure
Treatment of the precipitating condition

Botanical safety: Sedating herbs and essential-oil inhalation should not delay respiratory support. Ephedra can worsen tachycardia and cardiovascular risk.

Clinical Pearl: A patient with chronic CO₂ retention may have an elevated bicarbonate at baseline.

NPLEX Trap: Do not withhold oxygen from a severely hypoxemic COPD patient because of fear of CO₂ retention.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 52

Hyperosmolar Hyperglycemic StateClinical Case 52

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 78-year-old woman with type 2 diabetes is brought to the emergency department because of progressive confusion and weakness. She has had fever, cough, and reduced oral intake for five days. Medications:

Metformin
Sitagliptin Vital signs:
BP: 86/52 mmHg
HR: 124/min
RR: 22/min
Temperature: 38.7°C Physical examination:
Profoundly dehydrated
Lethargic
No Kussmaul respirations
No major abdominal tenderness Laboratory findings:
Glucose: 48 mmol/L
Effective serum osmolality: markedly elevated
Sodium: 151 mmol/L
Potassium: 4.8 mmol/L

Bicarbonate: 21 mmol/L
Venous pH: 7.36
Ketones: minimal
Creatinine: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Hyperosmolar hyperglycemic state

Extreme hyperglycemia, severe dehydration, hyperosmolality, neurologic dysfunction, minimal ketonemia, and absence of substantial acidosis are characteristic of hyperosmolar hyperglycemic state.

Q2

What is the initial treatment priority?

AImmediate large-dose insulin before fluidsBIntravenous isotonic fluid resuscitation with cardiovascular monitoringCSodium bicarbonateDFluid restrictionEOral glucose

Reveal answer and rationale

✓Correct answer: B. Intravenous isotonic fluid resuscitation with cardiovascular monitoring

Fluid loss is often profound in HHS. Initial management prioritizes restoration of circulation and tissue perfusion. Older patients may have heart or kidney disease, so fluid administration must be reassessed frequently.

Q3

Which precipitating factor is most likely in this case?

APneumonia or another infectionBExcessive insulin administrationCPrimary adrenal insufficiencyDCalcium supplementationEHyperthyroidism without illness

Reveal answer and rationale

✓Correct answer: A. Pneumonia or another infection

Infection is a common precipitant of hyperglycemic crises. Other triggers include myocardial infarction, stroke, medication interruption, glucocorticoids, and inadequate access to fluid.

Q4

Why must glucose and osmolality be corrected gradually?

ARapid shifts may contribute to serious neurologic complicationsBInsulin never lowers glucoseCSodium must always remain elevatedDKetones increase when osmolality fallsESlow treatment prevents all hypokalemia

Reveal answer and rationale

✓Correct answer: A. Rapid shifts may contribute to serious neurologic complications

Treatment requires careful correction of glucose, sodium, water deficit, and osmolality. Excessively rapid osmotic change may contribute to cerebral edema or other neurologic complications. The ADA 2026 Standards and the adult hyperglycemic-crisis consensus report emphasize fluids, electrolyte monitoring, insulin, precipitant treatment, and controlled correction of hyperosmolality.

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Diagnosis: Hyperosmolar hyperglycemic state precipitated by infection

Typical findings

Severe hyperglycemia
Marked dehydration
Increased serum osmolality
Altered mental status
Minimal ketosis
Little or no severe metabolic acidosis

Key investigations

Glucose
Electrolytes
Measured or calculated osmolality
Ketones
Venous pH and bicarbonate
Renal function
ECG
Infection evaluation
Cardiac and neurologic assessment when indicated

Treatment principles

Restore circulating volume.
Monitor and replace potassium appropriately.
Administer insulin after initial fluid and potassium assessment.
Correct osmolality gradually.
Treat the precipitating illness.
Monitor neurologic status and urine output.

Botanical medicine: Cinnamon, berberine, or other glucose-lowering supplements cannot treat HHS.

Clinical Pearl: HHS and DKA may overlap.

NPLEX Trap: A normal or elevated initial potassium does not exclude substantial total-body potassium depletion.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 53

Unstable Atrial Fibrillation with Rapid Ventricular ResponseClinical Case 53

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 72-year-old man presents with palpitations, chest pressure, severe dyspnea, and dizziness. Medical history:

Hypertension
Heart failure with reduced ejection fraction
Previous paroxysmal atrial fibrillation Vital signs:
BP: 74/42 mmHg
HR: 184/min and irregular
RR: 30/min
SpO₂: 88% Physical examination:
Diaphoretic and confused
Elevated jugular venous pressure
Bilateral crackles
Cool extremities ECG demonstrates an irregularly irregular narrow-complex tachycardia without identifiable P waves.

Q1

What is the most likely rhythm?

ASinus tachycardiaBAtrial fibrillation with rapid ventricular responseCComplete heart blockDVentricular fibrillationESinus bradycardia

Reveal answer and rationale

✓Correct answer: B. Atrial fibrillation with rapid ventricular response

An irregularly irregular rhythm, absent discrete P waves, and rapid ventricular rate indicate atrial fibrillation with rapid ventricular response.

Q2

What is the most appropriate immediate treatment?

AOral rate-control medication and dischargeBSynchronized electrical cardioversionCExercise to restore sinus rhythmDAspirin aloneEObservation until the rate slows naturally

Reveal answer and rationale

✓Correct answer: B. Synchronized electrical cardioversion

The patient has hypotension, altered mental status, ischemic chest discomfort, pulmonary edema, and shock. These are signs of hemodynamic instability requiring immediate synchronized cardioversion. The 2025 AHA adult advanced-life-support guidance recommends synchronized cardioversion for unstable tachyarrhythmias.

Q3

If the patient were stable, which general treatment goals would need to be considered?

ARate or rhythm control and stroke preventionBAntibiotics and bronchoscopyCCalcium replacement onlyDLong-term corticosteroidsENo follow-up if symptoms resolve

Reveal answer and rationale

✓Correct answer: A. Rate or rhythm control and stroke prevention

Atrial fibrillation management includes:

Symptom control through rate or rhythm management
Assessment of thromboembolic risk
Anticoagulation when indicated
Treatment of contributing conditions Current AHA/ACC guidance emphasizes stroke-risk assessment, symptom management, and modification of associated cardiovascular risks.

Q4

Which botanical product is concerning because it may increase bleeding risk if anticoagulation is prescribed?

Reveal answer and rationale

✓Correct answer: A. Ginkgo biloba

Ginkgo may influence platelet activity and should be documented when antiplatelet or anticoagulant therapy is being considered.

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Diagnosis: Hemodynamically unstable atrial fibrillation with rapid ventricular response

Potential precipitants

Infection
Myocardial ischemia
Heart failure
Hyperthyroidism
Alcohol
Electrolyte abnormalities
Pulmonary embolism
Medication interruption

Key investigations after immediate stabilization

ECG
Electrolytes and magnesium
CBC
Renal function
Troponin
Thyroid testing
Chest imaging
Echocardiography
Stroke-risk and bleeding-risk assessment

Treatment principles

Immediate synchronized cardioversion when unstable
Rate or rhythm control when stable
Anticoagulation assessment
Treatment of the precipitating cause
Long-term cardiovascular risk management

Clinical Pearl: Instability is determined by the patient’s clinical condition, not by heart rate alone.

NPLEX Trap: Do not delay cardioversion in an unstable patient while calculating a stroke-risk score.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 54

Placental AbruptionClinical Case 54

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 35-year-old woman at 34 weeks’ gestation presents with sudden severe abdominal pain and vaginal bleeding. Medical history:

Chronic hypertension
Tobacco use
Previous preeclampsia Vital signs:
BP: 92/58 mmHg
HR: 124/min
RR: 24/min Physical examination:
Uterus is firm, tender, and frequently contracting
Vaginal bleeding is moderate
Fetal heart tracing shows recurrent late decelerations
The patient appears pale and distressed Laboratory findings:
Hemoglobin: decreased
Platelets: 94 × 10⁹/L
Fibrinogen: decreased

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Placental abruption

Painful vaginal bleeding, uterine tenderness, increased uterine tone, frequent contractions, fetal distress, and maternal instability are characteristic of placental abruption. Placenta previa more commonly causes painless bleeding and a soft, nontender uterus.

Q2

What is the most appropriate management?

ADischarge with pelvic restBImmediate maternal resuscitation, continuous fetal assessment, obstetric activation, and expedited delivery when indicatedCPerform repeated digital vaginal examinationsDBegin an herbal uterine relaxantEDelay intervention until ultrasound confirms the diagnosis

Reveal answer and rationale

✓Correct answer: B. Immediate maternal resuscitation, continuous fetal assessment, obstetric activation, and expedited delivery when indicated

Management depends on maternal stability, fetal condition, gestational age, and bleeding severity. Maternal shock and fetal compromise require urgent resuscitation and delivery planning. Placental abruption is a potentially life-threatening obstetric emergency associated with hemorrhage and fetal compromise. ACOG identifies hypertension as an important associated risk and recognizes placental complications as indications for urgent obstetric care.

Q3

Which coagulation abnormality may develop in severe abruption?

ADisseminated intravascular coagulationBIsolated vitamin B12 deficiencyCPolycythemia onlyDFactor VIII excessEEssential thrombocythemia

Reveal answer and rationale

✓Correct answer: A. Disseminated intravascular coagulation

Severe abruption can release tissue factor and cause consumptive coagulopathy. Falling fibrinogen and platelets are concerning.

Q4

Which statement about visible bleeding is most accurate?

AVisible bleeding always reflects the total blood lossBSignificant blood may remain concealed behind the placentaCAbsence of external bleeding excludes abruptionDBleeding occurs only after membrane ruptureEMaternal vital signs remain normal in severe abruption

Reveal answer and rationale

✓Correct answer: B. Significant blood may remain concealed behind the placenta

External bleeding can underestimate the severity because blood may be trapped behind the placenta. Maternal instability may therefore appear disproportionate to visible blood loss.

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Diagnosis: Severe placental abruption with maternal hemorrhage, fetal compromise, and evolving coagulopathy

Risk factors

Hypertension
Preeclampsia
Previous abruption
Tobacco or cocaine exposure
Abdominal trauma
Premature membrane rupture
Multiple pregnancy
Sudden uterine decompression

Key assessments

Maternal airway and circulation
Fetal heart monitoring
CBC and platelets
Coagulation profile
Fibrinogen
Type and crossmatch
Renal and hepatic function
Ultrasound for supportive information

Treatment principles

Obstetric emergency activation
Intravenous access and blood-product preparation
Maternal resuscitation
Continuous fetal monitoring
Correction of coagulopathy
Delivery when maternal or fetal status requires it

Botanical safety: Uterine-stimulating or anticoagulant herbs are contraindicated.

Clinical Pearl: Ultrasound can be normal despite clinically significant abruption.

NPLEX Trap: Do not rule out abruption because vaginal bleeding appears limited.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 55

Acute EpiglottitisClinical Case 55

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 6-year-old child presents with rapidly progressive fever, severe sore throat, drooling, and difficulty breathing. The child is sitting upright, leaning forward, and refuses to lie down. Vital signs:

Temperature: 39.4°C
HR: 142/min
RR: 34/min
SpO₂: 90% Physical examination from a distance:
Muffled voice
Inspiratory stridor
Drooling
Marked anxiety
Minimal cough Vaccination history is incomplete.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute epiglottitis

Rapid onset of fever, toxic appearance, drooling, muffled voice, tripod positioning, dysphagia, and stridor strongly suggests epiglottitis. Croup more commonly produces a barking cough, hoarseness, and a less toxic appearance.

Q2

What is the most appropriate immediate action?

AForcefully examine the throat using a tongue depressorBKeep the child calm and upright while activating an expert airway teamCAsk the child to lie flatDObtain a throat swab before arranging helpEAdminister oral fluids

Reveal answer and rationale

✓Correct answer: B. Keep the child calm and upright while activating an expert airway team

Agitation or throat manipulation can precipitate complete airway obstruction. Airway examination and securing should occur in a controlled setting with skilled personnel.

Q3

What treatment is required after the airway has been addressed?

AIntravenous antimicrobial therapyBAntihistamine aloneCInhaled corticosteroid aloneDBotanical throat sprayEOral cough suppressant

Reveal answer and rationale

✓Correct answer: A. Intravenous antimicrobial therapy

Epiglottitis is treated as a serious bacterial upper-airway infection. Antimicrobial selection should cover likely organisms and consider local resistance patterns. Hib can cause invasive disease including epiglottitis, and vaccination substantially reduces the risk of Hib disease in children.

Q4

Which feature is more consistent with epiglottitis than viral croup?

ABarking coughBDrooling and refusal to swallowCGradual onset of mild hoarsenessDSymptoms only at nightEImprovement when crying

Reveal answer and rationale

✓Correct answer: B. Drooling and refusal to swallow

Drooling reflects severe odynophagia and difficulty handling secretions. It is a major warning sign for supraglottic obstruction.

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Diagnosis: Acute epiglottitis with threatened upper-airway obstruction

Possible organisms

Haemophilus influenzae
Streptococcal species
Staphylococcal species
Other bacterial pathogens

Key clinical features

High fever
Severe sore throat

Drooling
Dysphagia
Muffled voice
Tripod positioning
Stridor
Toxic appearance

Treatment principles

Avoid unnecessary agitation
Do not force a throat examination
Activate anesthesia, otolaryngology, and emergency airway support
Administer oxygen as tolerated
Secure the airway when required
Begin intravenous antibiotics
Provide intensive monitoring

Botanical safety: Throat sprays, steam inhalation, or oral remedies must not delay airway protection.

Clinical Pearl: The throat may appear relatively normal when viewed casually because the inflamed epiglottis is deeper in the airway.

NPLEX Trap: Do not use a tongue depressor in an unstable child with suspected epiglottitis outside a controlled airway setting.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 56

Organophosphate PoisoningClinical Case 56

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 43-year-old farm worker is brought to the emergency department after being found confused beside an open pesticide container. Assessment:

BP: 92/54 mmHg
HR: 48/min
RR: 10/min
SpO₂: 84%

Physical examination:

Pinpoint pupils
Profuse salivation
Sweating
Vomiting and diarrhea
Diffuse wheezing
Copious bronchial secretions
Muscle fasciculations
Progressive weakness

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Organophosphate poisoning

Organophosphates inhibit acetylcholinesterase and cause excessive cholinergic activity. Important manifestations include:

Salivation
Lacrimation
Urination
Diarrhea
Gastrointestinal cramping
Emesis
Bronchorrhea
Bradycardia
Miosis
Fasciculations and weakness

Q2

What is the immediate management priority?

AProtect rescuers, remove contaminated clothing, decontaminate appropriately, and support the airway and ventilationBInduce vomitingCGive oral charcoal before airway managementDPerform mouth-to-mouth ventilation without protective equipmentEDelay treatment until cholinesterase levels return

Reveal answer and rationale

✓Correct answer: A. Protect rescuers, remove contaminated clothing, decontaminate appropriately, and support the airway and ventilation

Secondary contamination of healthcare workers is possible. Personal protective equipment, removal from exposure, decontamination, suctioning, oxygenation, and ventilation are immediate priorities.

Q3

Which antidote treats muscarinic manifestations such as bronchorrhea and bradycardia?

Reveal answer and rationale

✓Correct answer: A. Atropine

Atropine competitively blocks muscarinic acetylcholine receptors. Dosing is guided clinically, especially by improvement in bronchial secretions and ventilation—not by pupil size alone.

Q4

What is the purpose of pralidoxime?

AReactivate acetylcholinesterase and improve nicotinic neuromuscular toxicityBReverse opioid receptorsCChelate ironDReduce acetaminophen metabolitesETreat methemoglobinemia

Reveal answer and rationale

✓Correct answer: A. Reactivate acetylcholinesterase and improve nicotinic neuromuscular toxicity

Pralidoxime can reactivate acetylcholinesterase before the enzyme-organophosphate bond permanently “ages.” It is typically used with atropine and is particularly important for weakness and respiratory-muscle dysfunction.

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Diagnosis: Severe organophosphate pesticide poisoning

Muscarinic manifestations

Bronchorrhea
Bronchospasm
Bradycardia
Miosis
Salivation
Vomiting
Diarrhea
Urination

Nicotinic manifestations

Fasciculations
Muscle weakness
Paralysis
Tachycardia or hypertension in some patients

Central manifestations

Confusion
Seizures
Coma
Respiratory depression

Treatment principles

Rescuer protection
Decontamination
Airway suction and ventilation
Atropine
Pralidoxime
Benzodiazepines for seizures
Continuous respiratory monitoring

Clinical Pearl: Respiratory failure may result from bronchorrhea, bronchospasm, central depression, and respiratory-muscle weakness simultaneously.

NPLEX Trap: Atropine treats muscarinic effects but does not adequately reverse skeletal-muscle weakness.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 57

Acute Deep-Vein ThrombosisClinical Case 57

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 58-year-old woman presents with two days of swelling, warmth, and aching of the left leg. History:

Total knee replacement three weeks ago
Reduced mobility
Obesity
Previous estrogen therapy Vital signs:
BP: 128/76 mmHg

HR: 96/min
RR: 18/min
SpO₂: 97% Physical examination:
Left calf circumference is 4 cm larger than the right
Pitting edema
Tenderness along the deep venous system
No chest pain or dyspnea
Pedal pulses are intact

Q1

What is the most likely diagnosis?

AAcute deep-vein thrombosisBAcute limb ischemiaCCellulitis confirmed by examinationDChronic lymphedemaELumbar radiculopathy

Reveal answer and rationale

✓Correct answer: A. Acute deep-vein thrombosis

Recent major orthopedic surgery, reduced mobility, unilateral swelling, pitting edema, and deep venous tenderness indicate a high probability of DVT.

Q2

What is the most appropriate diagnostic test?

Reveal answer and rationale

✓Correct answer: A. Compression venous ultrasonography

Compression ultrasound is the primary imaging test for suspected lower-extremity DVT. Clinical probability should guide testing. D-dimer is most useful for excluding DVT in appropriately selected patients with low clinical probability, not as a stand-alone test in high-probability cases.

Q3

If proximal DVT is confirmed and no contraindication exists, what treatment is generally indicated?

ATherapeutic anticoagulationBAntibiotics onlyCAspirin alone in every patientDVigorous massageEBed rest for several months without medication

Reveal answer and rationale

✓Correct answer: A. Therapeutic anticoagulation

Anticoagulation prevents clot extension, pulmonary embolism, and recurrence. Medication choice depends on renal function, pregnancy, malignancy, bleeding risk, interactions, and other individual factors.

Q4

Which new symptom requires immediate emergency evaluation?

AMild chronic knee stiffnessBSudden dyspnea, pleuritic chest pain, or syncopeCMild skin drynessDStable leg heavinessEToenail thickening

Reveal answer and rationale

✓Correct answer: B. Sudden dyspnea, pleuritic chest pain, or syncope

These symptoms raise concern for pulmonary embolism, a potentially life-threatening complication of DVT.

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Diagnosis: Provoked proximal lower-extremity DVT following orthopedic surgery

Major risk factors

Surgery
Trauma
Immobilization
Active cancer
Pregnancy and postpartum state
Estrogen exposure
Previous VTE
Thrombophilia

Key investigations

Clinical probability assessment
Compression ultrasonography
D-dimer in suitable low-probability patients
CBC
Renal and hepatic function
Pregnancy testing when relevant
Coagulation assessment

Treatment principles

Anticoagulation
Evaluate bleeding risk
Determine whether the event was provoked
Educate about pulmonary-embolism symptoms

Encourage appropriate mobility after treatment begins
Individualize treatment duration

Botanical safety: Ginkgo, high-dose garlic, or other supplements with potential bleeding effects should be reviewed during anticoagulation.

Physical medicine: Avoid vigorous massage over a suspected acute DVT.

Clinical Pearl: A negative Homan sign does not exclude DVT and should not guide diagnosis.

NPLEX Trap: Preserved arterial pulses do not rule out DVT.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 58

Cardiac TamponadeClinical Case 58

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 46-year-old woman with metastatic breast cancer presents with worsening dyspnea, weakness, and chest pressure. Vital signs:

BP: 78/48 mmHg
HR: 132/min
RR: 28/min
SpO₂: 91% Physical examination:
Elevated jugular venous pressure
Muffled heart sounds
Cool extremities
Clear lungs
Systolic blood pressure falls markedly during inspiration ECG demonstrates low-voltage QRS complexes and electrical alternans. Bedside ultrasound shows a large pericardial effusion with right-sided chamber collapse.

Q1

What is the most likely diagnosis?

AAcute left-sided heart failureBCardiac tamponadeCTension pneumothoraxDStable pericardial effusionEUncomplicated pneumonia

Reveal answer and rationale

✓Correct answer: B. Cardiac tamponade

Hypotension, elevated jugular venous pressure, muffled heart sounds, pulsus paradoxus, electrical alternans, and echocardiographic chamber collapse indicate cardiac tamponade.

Q2

What is the definitive emergency treatment?

Reveal answer and rationale

✓Correct answer: A. Urgent pericardial drainage

Hemodynamically significant tamponade requires urgent removal of pericardial fluid, usually by image-guided pericardiocentesis or surgical drainage depending on the cause and clinical setting.

Q3

Which intervention may worsen hemodynamics before drainage?

AAggressive diuresisBCareful intravenous fluid supportCEmergency echocardiographyDOxygen administrationESurgical consultation

Reveal answer and rationale

✓Correct answer: A. Aggressive diuresis

Patients with tamponade depend on adequate venous filling pressure. Diuresis or vasodilation may reduce preload and worsen shock. A cautious fluid bolus may temporarily support circulation while definitive drainage is arranged, but it is not definitive treatment.

Q4

What is pulsus paradoxus?

AAn inspiratory decrease in systolic blood pressure greater than expectedBComplete absence of a pulseCAlternating bradycardia and tachycardiaDIncreased systolic pressure during inspirationEA difference between arm and leg blood pressure

Reveal answer and rationale

✓Correct answer: A. An inspiratory decrease in systolic blood pressure greater than expected

An exaggerated inspiratory fall in systolic blood pressure reflects impaired left-ventricular filling during inspiration and supports the diagnosis of tamponade.

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Diagnosis: Malignant pericardial effusion causing cardiac tamponade

Potential causes

Malignancy
Pericarditis
Trauma
Aortic dissection
Cardiac procedure
Uremia
Tuberculosis
Anticoagulation-associated bleeding

Key investigations

Bedside echocardiography
ECG
Chest imaging
CBC
Renal function
Coagulation studies
Pericardial-fluid analysis when obtained

Treatment principles

Emergency cardiovascular consultation
Oxygen and monitoring
Temporary preload support when appropriate
Urgent pericardial drainage
Treatment of the underlying cause

Clinical Pearl: Beck triad may be incomplete, especially in slowly developing tamponade.

NPLEX Trap: Do not use aggressive diuresis for hypotension and elevated JVP without considering tamponade.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 59

Sustained Ventricular TachycardiaClinical Case 59

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 65-year-old man with previous myocardial infarction develops sudden palpitations, chest pain, and near-syncope. Vital signs:

BP: 76/44 mmHg
HR: 190/min
RR: 28/min
SpO₂: 90% ECG demonstrates a regular wide-complex tachycardia. The patient has a palpable pulse but is confused and diaphoretic.

Q1

What is the most likely diagnosis?

ASinus tachycardiaBSustained ventricular tachycardia with a pulseCAtrial fibrillationDComplete heart blockEVentricular fibrillation

Reveal answer and rationale

✓Correct answer: B. Sustained ventricular tachycardia with a pulse

A regular wide-complex tachycardia in a patient with structural heart disease should be treated as ventricular tachycardia unless clearly proven otherwise.

Q2

What is the most appropriate immediate treatment?

ASynchronized cardioversionBUnscheduled defibrillation while the patient has an organized pulseCOral beta-blocker and dischargeDVagal manoeuvres onlyEExercise stress testing

Reveal answer and rationale

✓Correct answer: A. Synchronized cardioversion

Hypotension, altered mental status, ischemic chest pain, and shock indicate an unstable tachyarrhythmia. Synchronized cardioversion is indicated. The 2025 AHA guidance recommends synchronized cardioversion for hemodynamically unstable wide-complex tachycardia with a pulse.

Q3

If the patient becomes pulseless, what is required?

AImmediate defibrillation and cardiac-arrest managementBSynchronized cardioversionCOral amiodaroneDCarotid massageEObservation for spontaneous conversion

Reveal answer and rationale

✓Correct answer: A. Immediate defibrillation and cardiac-arrest management

Pulseless ventricular tachycardia is a shockable cardiac-arrest rhythm and requires immediate CPR and unsynchronized defibrillation.

Q4

Which electrolyte disturbances can increase ventricular-arrhythmia risk?

AHypokalemia and hypomagnesemiaBMild hypernatremia onlyCIsolated elevated bicarbonateDMild hypophosphatemia onlyEHigh vitamin B12

Reveal answer and rationale

✓Correct answer: A. Hypokalemia and hypomagnesemia

Low potassium and magnesium can promote ventricular ectopy, QT-related arrhythmia, and treatment resistance. Electrolytes should be measured and corrected.

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Diagnosis: Hemodynamically unstable sustained ventricular tachycardia

Potential causes

Previous myocardial infarction and scar
Acute ischemia
Cardiomyopathy
Electrolyte disturbance
Drug-induced QT prolongation
Myocarditis
Inherited channelopathy

Treatment principles

Synchronized cardioversion when unstable with a pulse
Defibrillation and CPR if pulseless
Correct potassium and magnesium
Investigate ischemia
Antiarrhythmic medication when indicated
Evaluate for implantable defibrillator or ablation after stabilization

Botanical safety: Stimulants and products that prolong the QT interval should be reviewed.

Clinical Pearl: A wide-complex tachycardia in a patient with previous MI is ventricular tachycardia until proven otherwise.

NPLEX Trap: Do not give AV-nodal-blocking medication to an undifferentiated unstable wide-complex tachycardia.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 60

Severe HypokalemiaClinical Case 60

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 57-year-old woman presents with muscle weakness, constipation, palpitations, and difficulty walking. Medical history:

Hypertension
Chronic edema
Eating disorder history Medications and supplements:
Furosemide
Hydrochlorothiazide
Frequent stimulant-laxative use
Licorice-root extract Laboratory findings:
Potassium: 2.1 mmol/L
Magnesium: low
Bicarbonate: 34 mmol/L
Creatinine: normal ECG demonstrates:
Flattened T waves
ST depression
Prominent U waves
Frequent premature ventricular complexes

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Severe hypokalemia with cardiac electrical instability

Markedly reduced potassium with weakness, ileus-type symptoms, U waves, and ventricular ectopy indicates severe symptomatic hypokalemia.

Q2

What is the most appropriate management?

AMonitored potassium replacement, magnesium correction, and discontinuation of contributing agentsBReassure and repeat testing in one monthCAdminister insulin and glucoseDBegin a potassium-restricted dietEIncrease both diuretics

Reveal answer and rationale

✓Correct answer: A. Monitored potassium replacement, magnesium correction, and discontinuation of contributing agents

Severe symptomatic hypokalemia with ECG abnormalities requires urgent monitored replacement. The route and rate depend on symptom severity, ECG findings, renal function, and ability to take oral medication.

Q3

Why should magnesium deficiency be corrected?

AHypomagnesemia can cause ongoing renal potassium loss and make hypokalemia difficult to correctBMagnesium always directly raises sodiumCMagnesium prevents all medication interactionsDPotassium cannot enter the stomach without magnesiumEMagnesium eliminates the need for potassium replacement

Reveal answer and rationale

✓Correct answer: A. Hypomagnesemia can cause ongoing renal potassium loss and make hypokalemia difficult to correct

Low magnesium promotes renal potassium wasting and increases arrhythmia risk. Potassium replacement may remain ineffective until magnesium is corrected.

Q4

How can licorice contribute to this presentation?

AIt may cause an apparent mineralocorticoid effect with hypertension and renal potassium lossBIt directly causes adrenal failureCIt prevents sodium absorptionDIt produces metabolic acidosisEIt blocks all diuretic effects

Reveal answer and rationale

✓Correct answer: A. It may cause an apparent mineralocorticoid effect with hypertension and renal potassium loss

Glycyrrhizin-containing licorice can inhibit cortisol metabolism in the kidney, allowing cortisol to stimulate mineralocorticoid receptors. This may cause sodium retention, hypertension, metabolic alkalosis, and hypokalemia. Cases of licorice-containing supplements causing severe potassium depletion have been documented.

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Diagnosis: Severe hypokalemia caused by diuretics, laxative use, magnesium deficiency, and licorice exposure

Potential causes

Loop or thiazide diuretics
Vomiting
Diarrhea
Laxative abuse
Hyperaldosteronism
Licorice
Insulin or beta₂-agonist-related intracellular shift
Renal tubular disorders

Clinical features

Weakness
Cramps
Constipation or ileus
Rhabdomyolysis
Palpitations
Ventricular arrhythmia
Respiratory-muscle weakness

Key investigations

Repeat potassium
Magnesium
Renal function
Bicarbonate and acid-base status
ECG
Urinary potassium when the cause is uncertain
Medication, supplement, vomiting, and laxative history

Treatment principles

Cardiac monitoring for severe cases
Potassium replacement
Magnesium correction
Stop contributing medications or products
Treat the underlying cause

Recheck potassium frequently

Clinical Pearl: Serum potassium may fall further after insulin, beta₂-agonists, or correction of acidosis.

NPLEX Trap: Never administer concentrated intravenous potassium as a direct IV push.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 61

Symptomatic Complete Heart BlockClinical Case 61

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 78-year-old man presents with dizziness, weakness, chest discomfort, and near-syncope. Medications:

Metoprolol
Digoxin
Ramipril Vital signs:
BP: 76/44 mmHg
HR: 32/min
RR: 22/min
SpO₂: 93% ECG shows regular P waves and regular QRS complexes, but no consistent relationship between them.

Q1

What is the most likely diagnosis?

ASinus bradycardiaBComplete third-degree atrioventricular blockCAtrial fibrillationDFirst-degree AV blockEVentricular tachycardia

Reveal answer and rationale

✓Correct answer: B. Complete third-degree atrioventricular block

Independent atrial and ventricular activity with no consistent PR relationship indicates complete AV dissociation.

Q2

What is the immediate management priority?

AOutpatient cardiology referralBSupport airway and circulation while preparing transcutaneous pacingCExercise to increase the heart rateDAdminister a beta-blockerERecommend hawthorn

Reveal answer and rationale

✓Correct answer: B. Support airway and circulation while preparing transcutaneous pacing

The patient has hypotension, ischemic symptoms, and near-syncope from symptomatic bradycardia. Immediate pacing and emergency cardiovascular management are required.

Q3

Which medication may be attempted while pacing is prepared?

Reveal answer and rationale

✓Correct answer: A. Atropine

Atropine may be attempted in symptomatic bradycardia, but it is often ineffective in advanced infranodal complete heart block. Pacing must not be delayed. The 2025 AHA adult bradycardia algorithm recommends atropine initially, followed by transcutaneous pacing or epinephrine or dopamine infusion when atropine is ineffective.

Q4

Which medications require immediate review?

Reveal answer and rationale

✓Correct answer: A. Metoprolol and digoxin

Beta-blockers and digoxin can worsen AV nodal conduction and bradycardia.

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Diagnosis: Hemodynamically unstable complete heart block

Potential causes

Myocardial ischemia
Degenerative conduction disease
Beta-blockers
Calcium-channel blockers
Digoxin
Hyperkalemia
Myocarditis
Lyme carditis

Key investigations

ECG
Electrolytes and magnesium
Renal function
Cardiac biomarkers
Digoxin level when relevant
Thyroid testing
Echocardiography

Treatment principles

ABC stabilization
Atropine trial when appropriate
Transcutaneous pacing
Epinephrine or dopamine infusion when needed
Transvenous pacing
Definitive pacemaker assessment

NPLEX Trap: Do not delay pacing in an unstable patient because atropine has not yet been fully trialed.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 62

EclampsiaClinical Case 62

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 29-year-old woman at 37 weeks’ gestation develops a generalized tonic-clonic seizure. Before the seizure, she reported severe headache, flashing lights, and epigastric pain. Vital signs after the seizure:

BP: 184/118 mmHg
HR: 110/min
SpO₂: 90% Laboratory findings:
Platelets: 82 × 10⁹/L
AST: elevated
Creatinine: elevated
Urine protein: markedly elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Eclampsia

A new generalized seizure in a pregnant patient with severe hypertension and preeclamptic organ dysfunction is eclampsia until proven otherwise.

Q2

What is the first-line medication for seizure treatment and prevention of recurrence?

Reveal answer and rationale

✓Correct answer: A. Magnesium sulfate

Magnesium sulfate is the treatment of choice for eclamptic seizures and recurrence prevention.

Q3

Which additional issue requires urgent treatment?

Reveal answer and rationale

✓Correct answer: A. Severe persistent hypertension

Severe hypertension increases maternal stroke risk and requires prompt treatment with an appropriate rapid-acting antihypertensive.

Q4

What is the definitive treatment?

ADelivery after maternal stabilizationBBed rest until 40 weeksCHerbal diuretic therapyDLong-term anticonvulsant therapy without deliveryESodium restriction alone

Reveal answer and rationale

✓Correct answer: A. Delivery after maternal stabilization

Maternal stabilization comes first. Delivery is then arranged because placental delivery is the definitive treatment for eclampsia.

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Diagnosis: Eclampsia with severe preeclampsia and possible HELLP syndrome

Immediate management

Protect the airway
Position laterally when feasible
Provide oxygen
Administer magnesium sulfate
Treat severe hypertension
Assess maternal and fetal status
Arrange delivery after stabilization

Magnesium toxicity signs

Loss of deep-tendon reflexes
Respiratory depression
Reduced urine output
Cardiac conduction disturbance

Antidote: Intravenous calcium gluconate.

NPLEX Trap: Do not use benzodiazepines or phenytoin as routine first-line therapy when magnesium is available and appropriate.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 63

Rabies ExposureClinical Case 63

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A previously unvaccinated 34-year-old camper awakens and finds a bat flying in the bedroom. He is unsure whether he was bitten. The bat escapes and cannot be tested.

There is a small unexplained scratch on his forearm.

Q1

What is the most appropriate action?

ANo action because there is no confirmed biteBImmediate public-health risk assessment for rabies post-exposure prophylaxisCWait for symptomsDBegin oral antibiotics onlyEObtain rabies antibody testing before treatment

Reveal answer and rationale

✓Correct answer: B. Immediate public-health risk assessment for rabies post-exposure prophylaxis

Bat exposures may involve small, unrecognized bites. Public-health authorities should assess whether post-exposure prophylaxis is indicated.

Q2

What should initial wound care include?

AThorough washing with soap and waterBImmediate tight closure without cleaningCApplication of an herbal poulticeDVigorous massageENo cleaning because it spreads virus

Reveal answer and rationale

✓Correct answer: A. Thorough washing with soap and water

Immediate thorough wound cleansing reduces viral contamination and is an essential part of rabies exposure care.

Q3

For a previously unvaccinated immunocompetent person, standard post-exposure prophylaxis includes:

AVaccine onlyBRabies immune globulin plus a rabies-vaccine seriesCImmune globulin onlyDAntibiotics and tetanus vaccine onlyEObservation until neurologic symptoms occur

Reveal answer and rationale

✓Correct answer: B. Rabies immune globulin plus a rabies-vaccine series

Post-exposure prophylaxis generally includes wound care, human rabies immune globulin infiltrated around the wound when feasible, and vaccine on the recommended schedule.

Q4

Why must treatment occur before symptoms begin?

ASymptomatic rabies is almost always fatalBThe vaccine causes infection after symptoms startCRabies affects only the skinDAntibiotics become ineffectiveEImmune globulin becomes toxic

Reveal answer and rationale

✓Correct answer: A. Symptomatic rabies is almost always fatal

Rabies is preventable through timely post-exposure care, but once clinical neurologic disease appears, survival is exceptionally rare.

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Potential exposures

Bites
Scratches contaminated with saliva
Saliva contacting mucous membranes
Certain bat exposures without a recognized bite

Post-exposure principles

Immediate wound cleansing
Public-health consultation
Rabies immune globulin for eligible unvaccinated patients
Rabies vaccination
Tetanus and bacterial-wound assessment

NPLEX Trap: Do not wait for symptoms or for rabies antibody testing before initiating indicated prophylaxis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 64

Bacterial KeratitisClinical Case 64

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 25-year-old contact-lens user presents with severe right-eye pain, photophobia, redness, and reduced vision. She slept in her contact lenses and rinses them with tap water. Examination:

Diffuse conjunctival injection
Corneal opacity
Focal corneal ulcer
Purulent discharge
Reduced visual acuity

Q1

What is the most likely diagnosis?

AAllergic conjunctivitisBBacterial keratitis with corneal ulcerationCSubconjunctival hemorrhageDDry-eye syndromeEUncomplicated blepharitis

Reveal answer and rationale

✓Correct answer: B. Bacterial keratitis with corneal ulceration

Severe pain, photophobia, reduced vision, contact-lens exposure, and a corneal infiltrate indicate infectious keratitis.

Q2

What is the most appropriate next step?

ARoutine eye examination next monthBSame-day emergency ophthalmologic assessmentCPatch the eye and observeDBegin a topical corticosteroid aloneEContinue wearing the contact lens

Reveal answer and rationale

✓Correct answer: B. Same-day emergency ophthalmologic assessment

Corneal infection can progress rapidly to perforation, scarring, and permanent visual loss.

Q3

Which organism is particularly associated with contact-lens-related keratitis?

Reveal answer and rationale

✓Correct answer: A. Pseudomonas aeruginosa

Contact-lens use, especially overnight wear and poor hygiene, increases the risk of aggressive gram-negative keratitis.

Q4

Which treatment should be avoided before ophthalmologic evaluation?

ATopical corticosteroid monotherapyBRemoving the contact lensCMeasuring visual acuityDAvoiding eye rubbingEUrgent referral

Reveal answer and rationale

✓Correct answer: A. Topical corticosteroid monotherapy

Corticosteroids can worsen uncontrolled bacterial, fungal, or herpetic corneal infections and should not be started without specialist direction.

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Red flags in a red eye

Reduced vision
Severe pain

Photophobia
Corneal opacity
Irregular pupil
Contact-lens use
Recent surgery or trauma

Treatment principles

Stop contact-lens use
Urgent slit-lamp assessment
Corneal cultures in selected cases
Intensive topical antimicrobial treatment
Close follow-up

NPLEX Trap: Conjunctivitis generally does not cause marked photophobia or significant reduction in visual acuity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 65

Rapidly Progressive GlomerulonephritisClinical Case 65

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 48-year-old man presents with fatigue, dark urine, reduced urine output, shortness of breath, and coughing up blood. Laboratory findings:

Creatinine: rapidly rising
Hemoglobin: decreased
Urinalysis: dysmorphic red cells and red-cell casts
Urine protein: moderate
Chest imaging: bilateral pulmonary infiltrates

Q1

What is the most likely clinical syndrome?

ANephrotic syndrome onlyBPulmonary-renal syndrome with rapidly progressive glomerulonephritisCUncomplicated cystitisDPrerenal dehydrationEKidney stone

Reveal answer and rationale

✓Correct answer: B. Pulmonary-renal syndrome with rapidly progressive glomerulonephritis

Hemoptysis, pulmonary infiltrates, acute kidney injury, dysmorphic red cells, and red-cell casts indicate pulmonary hemorrhage with glomerular inflammation.

Q2

Which urinary finding most strongly supports glomerulonephritis?

Reveal answer and rationale

✓Correct answer: A. Red-cell casts

Red-cell casts indicate bleeding arising within the nephron and strongly support glomerular inflammation.

Q3

Which tests are important in the etiologic evaluation?

Reveal answer and rationale

✓Correct answer: A. ANCA and anti-glomerular-basement-membrane antibodies

Important causes include ANCA-associated vasculitis and anti-GBM disease. Complement levels, ANA, infection testing, and kidney biopsy may also be required.

Q4

What is the appropriate management?

AEmergency nephrology assessment and rapid immunosuppressive treatment when confirmed or strongly suspectedBOral antibiotics onlyCHigh-protein dietDHerbal diureticsEObservation for several weeks

Reveal answer and rationale

✓Correct answer: A. Emergency nephrology assessment and rapid immunosuppressive treatment when confirmed or strongly suspected

Untreated rapidly progressive glomerulonephritis can cause irreversible kidney failure and fatal pulmonary hemorrhage.

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Potential causes

ANCA-associated vasculitis
Anti-GBM disease

Lupus nephritis
Infection-associated glomerulonephritis
Immune-complex disease

Key investigations

Urinalysis and microscopy
Creatinine and electrolytes
CBC
Complement
ANCA
Anti-GBM antibodies
ANA and related serology
Chest imaging
Kidney biopsy

NPLEX Trap: Hemoptysis plus hematuria is not automatically pulmonary embolism; consider pulmonary-renal vasculitis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 66

Toxic MegacolonClinical Case 66

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 39-year-old woman with ulcerative colitis presents with fever, severe abdominal pain, bloody diarrhea, and progressive distension. Vital signs:

BP: 88/54 mmHg
HR: 132/min
Temperature: 39.2°C Examination:
Distended, tender abdomen
Reduced bowel sounds
Guarding Abdominal imaging demonstrates marked colonic dilation.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Toxic megacolon

Systemic toxicity, severe colitis, abdominal distension, and nonobstructive colonic dilation indicate toxic megacolon.

Q2

What is the most appropriate management?

AHospitalization with bowel rest, intravenous therapy, and urgent gastroenterology and surgical consultationBStimulant laxativeCColonoscopy with full bowel preparationDAntidiarrheal medication and dischargeEHigh-fibre diet

Reveal answer and rationale

✓Correct answer: A. Hospitalization with bowel rest, intravenous therapy, and urgent gastroenterology and surgical consultation

The patient requires intensive monitoring, fluid and electrolyte correction, treatment of severe colitis, infection evaluation, and early surgical involvement.

Q3

Which medication should be avoided?

ALoperamideBAppropriate intravenous corticosteroid when inflammatory colitis is the causeCIntravenous fluidDVenous-thromboembolism prophylaxis when appropriateEBroad infection assessment

Reveal answer and rationale

✓Correct answer: A. Loperamide

Antimotility medications can worsen colonic dilation and increase perforation risk.

Q4

Which finding requires immediate surgery?

AColonic perforation or uncontrolled deteriorationBMild anemiaCOne additional loose stoolDImproved heart rateEReduced abdominal distension

Reveal answer and rationale

✓Correct answer: A. Colonic perforation or uncontrolled deterioration

Perforation, peritonitis, uncontrolled hemorrhage, shock, or failure of intensive medical treatment requires urgent colectomy assessment.

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Potential triggers

Severe ulcerative colitis
Crohn colitis
C. difficile
Other infectious colitis
Antimotility drugs
Opioids

Treatment principles

Bowel rest
Intravenous fluids and electrolyte correction
Stop antimotility agents and opioids
Treat inflammatory or infectious cause
Serial examinations and imaging
Early surgical involvement

NPLEX Trap: Do not perform routine colonoscopy or bowel preparation in toxic megacolon because of perforation risk.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 67

Acute Bacterial Prostatitis with SepsisClinical Case 67

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 66-year-old man presents with fever, chills, dysuria, pelvic pain, and inability to urinate. Vital signs:

BP: 84/50 mmHg
HR: 126/min
Temperature: 39.5°C Examination:
Distended bladder
Prostate is markedly tender and boggy on gentle examination
Patient appears confused

Q1

What is the most likely diagnosis?

ABenign prostatic hyperplasia onlyBAcute bacterial prostatitis with sepsis and urinary retentionCProstate cancerDChronic pelvic pain syndromeEUncomplicated cystitis

Reveal answer and rationale

✓Correct answer: B. Acute bacterial prostatitis with sepsis and urinary retention

Acute febrile urinary symptoms, pelvic pain, a tender prostate, retention, hypotension, and confusion indicate severe bacterial prostatitis with systemic infection.

Q2

Which procedure should be avoided?

Reveal answer and rationale

✓Correct answer: A. Vigorous prostatic massage

Prostatic massage can cause severe pain and may promote bacteremia.

Q3

What is the most appropriate treatment?

AIntravenous antibiotics, sepsis resuscitation, and urinary-drainage assessmentBSaw palmetto onlyCOral fluids and dischargeDPelvic massageEObservation until cultures return

Reveal answer and rationale

✓Correct answer: A. Intravenous antibiotics, sepsis resuscitation, and urinary-drainage assessment

Hemodynamic instability requires hospitalization, rapid antimicrobial treatment, and management of urinary obstruction.

Q4

Which drainage method may be preferred when urethral catheterization is difficult or risks worsening prostatic trauma?

ASuprapubic catheterizationBRepeated forceful urethral catheter attemptsCNo drainage despite retentionDProstatic massageENephrectomy

Reveal answer and rationale

✓Correct answer: A. Suprapubic catheterization

Urology may use suprapubic drainage when significant retention is present and urethral instrumentation is unsafe or unsuccessful.

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Common organisms

Enteric gram-negative bacteria
Escherichia coli
Other urinary pathogens

Potential complications

Sepsis
Prostatic abscess
Urinary retention
Chronic bacterial prostatitis
Epididymo-orchitis

NPLEX Trap: Saw palmetto is not treatment for acute bacterial prostatitis or septic shock.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 68

Acute Chest SyndromeClinical Case 68

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 22-year-old man with sickle cell disease presents with fever, chest pain, cough, and shortness of breath. Vital signs:

Temperature: 39.0°C
HR: 124/min
RR: 30/min
SpO₂: 86% Chest imaging shows a new right-lower-lobe infiltrate. Hemoglobin is below his baseline.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Acute chest syndrome

A new pulmonary infiltrate with fever, chest symptoms, hypoxemia, or respiratory findings in a person with sickle cell disease indicates acute chest syndrome.

Q2

What is the appropriate management?

AHospitalization, oxygen, pain control, antibiotics, and respiratory supportBDischarge with oral fluidsCHigh-dose opioid without monitoringDIron supplementation onlyEVigorous exercise

Reveal answer and rationale

✓Correct answer: A. Hospitalization, oxygen, pain control, antibiotics, and respiratory support

Acute chest syndrome can progress rapidly to respiratory failure. Incentive spirometry, cautious fluid management, and transfusion assessment may also be required.

Q3

Which treatment may be required in severe or rapidly progressive disease?

Reveal answer and rationale

✓Correct answer: A. Red-cell transfusion or exchange transfusion

Transfusion reduces the proportion of sickled erythrocytes and improves oxygen-carrying capacity.

Q4

Which analgesic-related complication can worsen the condition?

AOpioid-induced hypoventilationBAcetaminophen-related bronchodilationCAspirin-induced polycythemiaDIbuprofen-induced increased oxygenationELidocaine-induced hemolysis in all patients

Reveal answer and rationale

✓Correct answer: A. Opioid-induced hypoventilation

Pain must be treated, but excessive sedation and hypoventilation can worsen atelectasis and hypoxemia.

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Potential triggers

Infection
Pulmonary infarction
Fat embolism
Hypoventilation

Atelectasis
Postoperative state

Treatment principles

Oxygen
Antibiotics
Analgesia with respiratory monitoring
Incentive spirometry
Transfusion assessment
Venous-thromboembolism assessment
Intensive care when deteriorating

NPLEX Trap: Do not label chest pain as an uncomplicated vaso-occlusive crisis when hypoxemia and a new infiltrate are present.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 69

Infant BronchiolitisClinical Case 69

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 4-month-old infant presents with nasal congestion, cough, poor feeding, and increasing respiratory difficulty. Vital signs:

RR: 62/min
SpO₂: 88%
Temperature: 38.0°C Examination:
Nasal flaring
Subcostal retractions
Diffuse crackles and wheezing
Reduced oral intake
Fewer wet diapers

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Viral bronchiolitis

An infant with an upper-respiratory prodrome followed by wheezing, crackles, tachypnea, and feeding difficulty most likely has bronchiolitis.

Q2

What is the primary treatment?

ASupportive care with oxygen and hydration when requiredBRoutine antibioticsCRoutine systemic corticosteroidsDRoutine salbutamol for every infantECodeine cough syrup

Reveal answer and rationale

✓Correct answer: A. Supportive care with oxygen and hydration when required

Treatment is mainly supportive: nasal suctioning, hydration, oxygen for significant hypoxemia, and respiratory monitoring.

Q3

Which feature supports hospitalization?

Reveal answer and rationale

✓Correct answer: A. Hypoxemia and poor feeding

Young age, apnea, dehydration, significant retractions, hypoxemia, and underlying cardiopulmonary disease increase risk.

Q4

Which treatment should be avoided?

AHoney for cough in this four-month-old infantBNasal suctioningCOxygen when indicatedDHydration assessmentEMonitoring for apnea

Reveal answer and rationale

✓Correct answer: A. Honey for cough in this four-month-old infant

Honey should not be given to infants younger than 12 months because of infant botulism risk.

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Common cause: Respiratory syncytial virus, although several viruses may cause bronchiolitis.

Red flags

Apnea

Cyanosis
Exhaustion
Dehydration
Persistent hypoxemia
Reduced consciousness

NPLEX Trap: Wheezing in an infant with bronchiolitis does not automatically mean asthma or require routine bronchodilator therapy.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 70

Moderate-to-Severe Viral CroupClinical Case 70

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 2-year-old child develops a barking cough, hoarse voice, and noisy breathing after two days of mild upper-respiratory symptoms. Examination:

Inspiratory stridor at rest
Suprasternal retractions
Agitation
No drooling
No tripod position

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Viral croup

A barking cough, hoarseness, and inspiratory stridor after a viral prodrome are typical of croup.

Q2

Which medication is indicated?

Reveal answer and rationale

✓Correct answer: A. Dexamethasone

A corticosteroid reduces upper-airway edema and is beneficial across croup severity levels.

Q3

Which treatment is appropriate for stridor at rest with significant retractions?

ANebulized epinephrineBOral decongestantCChest physiotherapyDThroat examination with a tongue depressorECough suppressant

Reveal answer and rationale

✓Correct answer: A. Nebulized epinephrine

Nebulized epinephrine rapidly reduces airway swelling but has a temporary effect, so observation for recurrence is required.

Q4

Which finding suggests an alternative diagnosis such as epiglottitis?

Reveal answer and rationale

✓Correct answer: A. Drooling and refusal to swallow

Drooling, tripod posture, toxic appearance, and minimal cough are more concerning for epiglottitis.

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Treatment principles

Keep the child calm
Dexamethasone
Nebulized epinephrine for moderate or severe disease
Oxygen when required
Observation after epinephrine
Airway escalation when exhaustion develops

NPLEX Trap: Improvement immediately after epinephrine does not always permit immediate discharge because symptoms can recur.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 71

Neonatal SepsisClinical Case 71

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 10-day-old infant presents with poor feeding, lethargy, temperature instability, and episodes of apnea. Vital signs:

Temperature: 35.7°C
HR: 178/min
RR: irregular
SpO₂: 89% Examination:
Weak cry
Reduced tone
Delayed capillary refill
Mottled skin

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Neonatal sepsis

Poor feeding, lethargy, hypothermia, apnea, poor perfusion, and respiratory instability in a neonate strongly suggest serious infection.

Q2

What is the appropriate management?

AImmediate hospital evaluation, cultures, and empiric intravenous antibioticsBObserve at homeCHerbal immune supportDOral water supplementationEDelay treatment until culture results return

Reveal answer and rationale

✓Correct answer: A. Immediate hospital evaluation, cultures, and empiric intravenous antibiotics

Neonatal sepsis can deteriorate rapidly. Cultures should be obtained promptly when feasible, but antimicrobial treatment must not be dangerously delayed.

Q3

Which organisms are important causes of early neonatal sepsis?

AGroup B streptococcus and gram-negative enteric organismsBH. pylori onlyCDermatophytesDC. difficile onlyEBorrelia only

Reveal answer and rationale

✓Correct answer: A. Group B streptococcus and gram-negative enteric organisms

Group B streptococcus and organisms such as E. coli are important neonatal pathogens.

Q4

Which statement is most accurate?

ANeonates with serious infection may be hypothermic rather than febrileBFever is always presentCNormal crying excludes infectionDPoor feeding is never significantEApnea indicates uncomplicated reflux

Reveal answer and rationale

✓Correct answer: A. Neonates with serious infection may be hypothermic rather than febrile

Temperature instability, including hypothermia, is a major neonatal infection warning sign.

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Key investigations

Blood cultures
CBC
Glucose and electrolytes
Urine culture
Lumbar puncture when appropriate
Chest imaging when respiratory symptoms are present

Treatment principles

ABC stabilization
Glucose correction
Empiric intravenous antibiotics
Respiratory support
Treatment adjusted to cultures

NPLEX Trap: Do not dismiss poor feeding and temperature instability as nonspecific newborn behaviour.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 72

Testicular TorsionClinical Case 72

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 16-year-old boy presents with sudden severe left testicular pain and vomiting. Examination:

Left testicle is high-riding
Testicle lies horizontally
Cremasteric reflex is absent
Marked tenderness
No urinary symptoms

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Testicular torsion

Sudden severe pain, vomiting, a high-riding transverse testicle, and absent cremasteric reflex are classic for torsion.

Q2

What is the most appropriate next step?

AImmediate surgical explorationBWait for urine-culture resultsCOral antibiotics and follow-upDMassage the testicleEBed rest for 48 hours

Reveal answer and rationale

✓Correct answer: A. Immediate surgical exploration

Testicular viability decreases as ischemia continues. Surgery must not be delayed when clinical suspicion is high.

Q3

What is the role of Doppler ultrasound?

AIt may support diagnosis when it does not delay surgeryBIt must always be performed before consultationCNormal flow permanently excludes torsionDIt treats the torsionEIt is useful only after orchiectomy

Reveal answer and rationale

✓Correct answer: A. It may support diagnosis when it does not delay surgery

Ultrasound may assess blood flow, but high clinical suspicion warrants immediate surgical action.

Q4

What additional procedure is generally performed during surgery?

Reveal answer and rationale

✓Correct answer: A. Fixation of both testes

The contralateral testis is usually fixed because the underlying anatomic predisposition is often bilateral.

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Differentials

Epididymitis
Torsion of appendix testis
Incarcerated hernia
Trauma
Tumour

NPLEX Trap: Do not delay surgery for imaging when the presentation is classic.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 73

Tubo-Ovarian AbscessClinical Case 73

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 31-year-old woman presents with fever, lower abdominal pain, purulent vaginal discharge, nausea, and dyspareunia. Vital signs:

Temperature: 39.1°C
HR: 122/min
BP: 98/60 mmHg Examination:
Cervical-motion tenderness
Bilateral adnexal tenderness
Tender left adnexal mass Ultrasound shows a complex tubo-ovarian collection.

Q1

What is the most likely diagnosis?

AUncomplicated bacterial vaginosisBPelvic inflammatory disease with tubo-ovarian abscessCEndometriosis onlyDCystitisEMittelschmerz

Reveal answer and rationale

✓Correct answer: B. Pelvic inflammatory disease with tubo-ovarian abscess

Fever, pelvic pain, cervical-motion tenderness, adnexal tenderness, discharge, and a complex adnexal collection indicate PID complicated by abscess.

Q2

What is the appropriate management?

AHospitalization and broad-spectrum intravenous antibioticsBRoutine outpatient follow-up onlyCVaginal douchingDHerbal suppositoriesENo treatment until cultures return

Reveal answer and rationale

✓Correct answer: A. Hospitalization and broad-spectrum intravenous antibiotics

A tubo-ovarian abscess requires broad anaerobic and sexually transmitted pathogen coverage, close monitoring, and possible drainage or surgery.

Q3

Which complication is most immediately life-threatening?

Reveal answer and rationale

✓Correct answer: A. Abscess rupture with peritonitis and sepsis

Rupture can produce rapid septic deterioration and requires emergency surgical management.

Q4

Which longer-term complication can follow PID?

Reveal answer and rationale

✓Correct answer: A. Infertility and ectopic pregnancy

Tubal inflammation and scarring increase infertility, chronic pelvic pain, and ectopic-pregnancy risk.

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Treatment principles

Pregnancy testing
STI testing
Broad antimicrobial treatment
Partner evaluation and treatment
Abstinence until therapy is complete
Drainage or surgery when necessary

NPLEX Trap: Negative cervical STI testing does not exclude upper-genital-tract infection.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 74

Neuroleptic Malignant SyndromeClinical Case 74

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 45-year-old man with schizophrenia develops fever, confusion, generalized rigidity, and diaphoresis three days after receiving a high-potency antipsychotic injection. Vital signs:

Temperature: 40.2°C
HR: 138/min
BP: fluctuating
RR: 28/min Laboratory findings:
Creatine kinase: 14,000 U/L
Creatinine: elevated
WBC: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Neuroleptic malignant syndrome

Recent dopamine-antagonist exposure with severe hyperthermia, altered consciousness, autonomic instability, lead-pipe rigidity, and elevated CK indicates NMS.

Q2

What is the first management step?

AStop the antipsychotic and begin intensive supportive careBGive another antipsychoticCBegin an SSRIDDischarge after acetaminophenEApply physical restraints continuously

Reveal answer and rationale

✓Correct answer: A. Stop the antipsychotic and begin intensive supportive care

The offending drug must be discontinued immediately. Cooling, fluids, electrolyte management, and treatment of complications are essential.

Q3

Which complication is suggested by the elevated CK?

Reveal answer and rationale

✓Correct answer: A. Rhabdomyolysis

Severe muscular rigidity can cause muscle breakdown, hyperkalemia, and acute kidney injury.

Q4

Which finding favours serotonin syndrome rather than NMS?

AClonus and hyperreflexiaBLead-pipe rigidityCRecent antipsychotic exposureDSlowly developing rigidityEMarkedly elevated CK

Reveal answer and rationale

✓Correct answer: A. Clonus and hyperreflexia

Serotonin syndrome usually produces hyperreflexia and clonus; NMS more commonly causes generalized rigidity and reduced or normal reflexes.

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Potential treatments in severe cases

Benzodiazepines
Bromocriptine
Dantrolene
Intensive care
Dialysis for severe renal complications when indicated

NPLEX Trap: Antipyretics alone do not correct drug-induced hyperthermia and muscular rigidity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 75

Lithium ToxicityClinical Case 75

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 60-year-old woman taking lithium for bipolar disorder develops vomiting, coarse tremor, slurred speech, confusion, and unsteady gait. She recently developed gastroenteritis and started ibuprofen. Laboratory findings:

Lithium: markedly elevated
Creatinine: elevated
Sodium: mildly reduced

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Lithium toxicity

Gastrointestinal symptoms, coarse tremor, dysarthria, ataxia, confusion, kidney injury, and elevated lithium indicate toxicity.

Q2

Which factors likely precipitated toxicity?

ADehydration, kidney dysfunction, and NSAID useBIncreased dietary fibreCVitamin B12DCalcium carbonateETopical moisturizer

Reveal answer and rationale

✓Correct answer: A. Dehydration, kidney dysfunction, and NSAID use

Volume depletion increases renal lithium reabsorption. NSAIDs can reduce renal lithium clearance.

Q3

What is the appropriate initial treatment?

AStop lithium and provide isotonic intravenous fluids with close monitoringBGive another lithium doseCFluid restrictionDInduce vomitingEAdminister activated charcoal routinely

Reveal answer and rationale

✓Correct answer: A. Stop lithium and provide isotonic intravenous fluids with close monitoring

Lithium is not effectively bound by activated charcoal. Hydration improves renal elimination when cardiac and renal status allow.

Q4

Which treatment may be required for severe neurologic toxicity or impaired clearance?

Reveal answer and rationale

✓Correct answer: A. Hemodialysis

Lithium is dialyzable. Severe neurologic manifestations, dangerous concentrations, or poor renal elimination may warrant hemodialysis.

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Interacting medications

NSAIDs
ACE inhibitors
ARBs
Thiazide diuretics

NPLEX Trap: Serum concentration does not always correlate perfectly with clinical severity, especially in chronic toxicity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 76

Digoxin ToxicityClinical Case 76

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

An 81-year-old woman taking digoxin presents with nausea, poor appetite, confusion, and yellow-green visual disturbances. Vital signs:

HR: 42/min

BP: 88/54 mmHg Laboratory findings:
Potassium: 6.1 mmol/L
Creatinine: elevated
Digoxin level: elevated ECG demonstrates bradycardia with AV block and ventricular ectopy.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Digoxin toxicity

Gastrointestinal symptoms, confusion, colour-vision changes, bradyarrhythmia, ventricular ectopy, kidney impairment, and hyperkalemia indicate severe digoxin toxicity.

Q2

Which treatment is indicated for life-threatening toxicity?

Reveal answer and rationale

✓Correct answer: A. Digoxin-specific antibody fragments

Digoxin immune Fab binds circulating digoxin and is used for severe arrhythmia, hemodynamic instability, significant hyperkalemia, or major overdose.

Q3

Which electrolyte deficiency increases susceptibility to digoxin toxicity?

Reveal answer and rationale

✓Correct answer: A. Hypokalemia

Hypokalemia increases digoxin binding to the sodium-potassium ATPase and raises arrhythmia risk.

Q4

Which patient factor contributed to toxicity?

Reveal answer and rationale

✓Correct answer: A. Reduced kidney function

Digoxin is substantially cleared by the kidneys, so reduced renal function increases accumulation.

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Possible manifestations

Nausea
Vomiting
Confusion
Visual colour changes
Bradycardia
AV block
Atrial or ventricular arrhythmias

NPLEX Trap: Do not rely only on the serum digoxin level; treat the patient’s clinical toxicity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 77

Beta-Blocker OverdoseClinical Case 77

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 36-year-old man is found after ingesting a large amount of propranolol. Vital signs:

BP: 66/38 mmHg
HR: 34/min
RR: 14/min Clinical findings:
Confusion
Cool extremities
Hypoglycemia
Wide QRS complexes
Generalized seizure

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Beta-blocker toxicity

Profound bradycardia, hypotension, hypoglycemia, seizure, and wide-complex conduction disturbance after propranolol ingestion indicate severe beta-blocker poisoning.

Q2

What is the immediate priority?

Reveal answer and rationale

✓Correct answer: A. ABC stabilization and poison-centre consultation

Airway, ventilation, perfusion, glucose, seizures, and conduction abnormalities must be treated immediately.

Q3

Which antidotal treatment can increase cardiac cyclic AMP independently of beta receptors?

Reveal answer and rationale

✓Correct answer: A. Glucagon

Glucagon may increase heart rate and contractility, although vomiting is common and airway protection is important.

Q4

Which therapy is often used in severe refractory cardiogenic shock?

Reveal answer and rationale

✓Correct answer: A. High-dose insulin with glucose and intensive monitoring

High-dose insulin supports myocardial energy use and contractility. Glucose and potassium require frequent monitoring.

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Additional therapies may include

Atropine
Vasopressors
Sodium bicarbonate for propranolol-associated QRS widening
Intravenous lipid emulsion in selected cases
Extracorporeal support

NPLEX Trap: Glucagon is not a substitute for full resuscitation and intensive hemodynamic support.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 78

Tricyclic Antidepressant OverdoseClinical Case 78

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 28-year-old woman is found confused beside an empty amitriptyline bottle. Vital signs:

BP: 78/46 mmHg
HR: 138/min
Temperature: 38.3°C Clinical findings:
Dilated pupils
Dry skin
Urinary retention
Seizure ECG:
QRS duration: 148 milliseconds
Terminal R wave in aVR

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Tricyclic-antidepressant toxicity

Anticholinergic findings, hypotension, seizure, QRS widening, and characteristic aVR changes indicate TCA sodium-channel blockade.

Q2

What is the primary treatment for QRS widening and hypotension?

Reveal answer and rationale

✓Correct answer: A. Intravenous sodium bicarbonate

Sodium bicarbonate narrows the QRS, improves blood pressure, and reduces ventricular-arrhythmia risk.

Q3

Which medication is appropriate for seizures?

Reveal answer and rationale

✓Correct answer: A. Benzodiazepine

Benzodiazepines are preferred. Phenytoin can worsen sodium-channel blockade and is generally avoided.

Q4

Which antiarrhythmic should be avoided?

AProcainamideBSodium bicarbonateCLidocaine in selected refractory casesDMagnesium for torsades when indicatedESupportive vasopressor therapy

Reveal answer and rationale

✓Correct answer: A. Procainamide

Class IA and IC antiarrhythmics can worsen sodium-channel blockade and conduction delay.

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Major toxic effects

Anticholinergic syndrome
Seizures
Hypotension

QRS widening
Ventricular arrhythmia
Coma

NPLEX Trap: A mildly elevated TCA blood level is less useful than ECG findings and clinical toxicity.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 79

Methanol PoisoningClinical Case 79

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 44-year-old man presents with headache, vomiting, abdominal pain, blurred “snowfield” vision, and confusion after drinking homemade alcohol. Laboratory findings:

Severe high-anion-gap metabolic acidosis
Elevated osmolar gap
Bicarbonate: 8 mmol/L
Creatinine: normal

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Methanol poisoning

Visual symptoms, severe anion-gap acidosis, elevated osmolar gap, and ingestion of illicit alcohol indicate methanol toxicity.

Q2

Which toxic metabolite causes ocular and metabolic injury?

Reveal answer and rationale

✓Correct answer: A. Formic acid

Methanol is metabolized to formaldehyde and then formic acid, which damages the optic nerve and causes severe acidosis.

Q3

Which antidote blocks alcohol dehydrogenase?

Reveal answer and rationale

✓Correct answer: A. Fomepizole

Fomepizole prevents conversion of methanol into its toxic metabolites.

Q4

Which additional treatment may be required in severe toxicity?

Reveal answer and rationale

✓Correct answer: A. Hemodialysis

Dialysis removes methanol and formate and corrects severe acidosis, especially when visual symptoms or major metabolic abnormalities are present.

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Key investigations

Blood gas
Electrolytes
Anion gap
Osmolar gap
Methanol concentration
Renal function
Glucose
Toxicology consultation

Additional treatments

Sodium bicarbonate
Folinic or folic acid
Intensive supportive care

NPLEX Trap: A normal osmolar gap later in the course does not exclude methanol poisoning after toxic metabolites have accumulated.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 80

Salicylate ToxicityClinical Case 80

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 70-year-old woman presents with nausea, vomiting, tinnitus, sweating, rapid breathing, and confusion. She has been taking large amounts of aspirin for arthritis. Vital signs:

Temperature: 38.4°C
HR: 122/min
RR: 34/min Laboratory findings:
Mixed respiratory alkalosis and high-anion-gap metabolic acidosis
Potassium: low
Glucose: normal
Salicylate concentration: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: A. Salicylate toxicity

Tinnitus, vomiting, diaphoresis, hyperventilation, fever, confusion, and a mixed acid-base disorder are characteristic.

Q2

Why is the patient hyperventilating?

ASalicylates directly stimulate the respiratory centre and metabolic acidosis further increases ventilationBThe patient has opioid respiratory depressionCAspirin causes airway obstructionDHyperventilation is unrelatedEThe patient has isolated anxiety

Reveal answer and rationale

✓Correct answer: A. Salicylates directly stimulate the respiratory centre and metabolic acidosis further increases ventilation

Early toxicity causes respiratory alkalosis; metabolic acidosis develops as toxicity progresses.

Q3

What treatment enhances salicylate elimination?

AIntravenous sodium bicarbonate with potassium correctionBFluid restrictionCUrine acidificationDNaloxoneECalcium supplementation

Reveal answer and rationale

✓Correct answer: A. Intravenous sodium bicarbonate with potassium correction

Serum and urine alkalinization reduces tissue penetration and increases renal salicylate excretion. Hypokalemia must be corrected for effective urine alkalinization.

Q4

Which condition supports emergency hemodialysis?

ASevere neurologic symptoms, pulmonary edema, kidney failure, severe acidosis, or clinical deteriorationBMild tinnitus onlyCA normal mental statusDOne therapeutic aspirin doseEMild chronic arthritis

Reveal answer and rationale

✓Correct answer: A. Severe neurologic symptoms, pulmonary edema, kidney failure, severe acidosis, or clinical deterioration

Dialysis rapidly removes salicylate and corrects metabolic and fluid complications.

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Major manifestations

Tinnitus
Nausea and vomiting
Hyperventilation
Fever
Hypokalemia
Hypoglycemia within the CNS despite normal serum glucose
Pulmonary edema
Confusion or seizure

Airway warning: Intubation can worsen toxicity if the patient’s high minute ventilation is not maintained.

NPLEX Trap: Do not delay dialysis solely because the serum concentration is declining when the patient is clinically deteriorating.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 81

Meningococcemia with Septic ShockClinical Case 81

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 19-year-old university learner presents with fever, severe headache, vomiting, confusion, and a rapidly spreading rash. Vital signs:

BP: 76/42 mmHg
HR: 138/min
RR: 30/min
Temperature: 40.0°C
SpO₂: 91% Physical examination:
Nuchal rigidity
Cool extremities
Delayed capillary refill
Nonblanching petechiae and purpura over the trunk and legs

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Meningococcal meningitis with meningococcemia

Fever, meningismus, altered mental status, shock, and a rapidly progressive nonblanching rash strongly suggest invasive meningococcal disease.

Q2

What is the most appropriate immediate management?

AWait for lumbar-puncture resultsBEmergency stabilization and immediate intravenous antimicrobial therapyCOral antibiotics and home observationDAntihistamine treatmentEBotanical antimicrobial therapy

Reveal answer and rationale

✓Correct answer: B. Emergency stabilization and immediate intravenous antimicrobial therapy

This is a rapidly fatal infection. Blood cultures should be obtained promptly when feasible, but treatment must not be delayed for lumbar puncture or imaging.

Q3

Which infection-control precaution is initially required?

Reveal answer and rationale

✓Correct answer: B. Droplet precautions

Respiratory droplets transmit meningococcal infection. Appropriate precautions are required until effective antimicrobial treatment has substantially reduced transmission risk.

Q4

What should be offered to appropriate close contacts?

APost-exposure antimicrobial prophylaxisBAspirinCAntifungal therapyDNo intervention unless symptoms appearEVitamin C only

Reveal answer and rationale

✓Correct answer: A. Post-exposure antimicrobial prophylaxis

Household members and other qualifying close contacts require prompt public-health assessment and chemoprophylaxis.

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Diagnosis: Invasive meningococcal disease causing meningitis, septic shock, and purpura

Key investigations

Blood cultures
CBC
Electrolytes and renal function
Lactate
Coagulation profile
Lumbar puncture when safe
Evaluation for disseminated intravascular coagulation

Treatment principles

ABC stabilization
Immediate intravenous antibiotics
Fluid and vasopressor support
Droplet precautions
Public-health notification

Contact prophylaxis

Clinical Pearl: A nonblanching rash in a febrile, unwell patient is a medical emergency.

NPLEX Trap: Do not delay antibiotics while waiting for lumbar puncture.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 82

Acute Severe Ulcerative ColitisClinical Case 82

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 32-year-old woman with ulcerative colitis presents with eight bloody bowel movements daily, abdominal pain, fever, and weakness. Vital signs:

BP: 96/60 mmHg
HR: 118/min
Temperature: 38.5°C Laboratory findings:
Hemoglobin: decreased
CRP: markedly elevated
Albumin: low
Potassium: low Abdominal examination shows diffuse tenderness without marked distension.

Q1

What is the most likely diagnosis?

AIrritable bowel syndromeBAcute severe ulcerative colitisCUncomplicated hemorrhoidsDViral gastroenteritisEFunctional diarrhea

Reveal answer and rationale

✓Correct answer: B. Acute severe ulcerative colitis

Frequent bloody stools combined with systemic toxicity, anemia, inflammation, and electrolyte disturbance indicate a severe inflammatory-colitis flare.

Q2

What is the most appropriate management?

AHospital admission and intravenous corticosteroid treatment after infection assessmentBOral loperamide and dischargeCHigh-fibre supplementationDStimulant laxativeERoutine outpatient colonoscopy

Reveal answer and rationale

✓Correct answer: A. Hospital admission and intravenous corticosteroid treatment after infection assessment

Acute severe ulcerative colitis requires inpatient care, infection exclusion, intravenous treatment, thrombosis prevention, and early surgical involvement.

Q3

Which investigation is important before escalating immunosuppression?

AStool testing for infectious causes, including C. difficileBExercise stress testingCPulmonary-function testingDSerum uric acidESkin-prick testing

Reveal answer and rationale

✓Correct answer: A. Stool testing for infectious causes, including C. difficile

Infection can mimic or worsen inflammatory colitis and may alter treatment.

Q4

Which medication should generally be avoided?

ALoperamideBIntravenous fluidCElectrolyte replacementDVenous-thromboembolism prophylaxisECorticosteroid therapy when indicated

Reveal answer and rationale

✓Correct answer: A. Loperamide

Antimotility therapy may increase the risk of toxic megacolon in severe inflammatory colitis.

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Potential complications

Toxic megacolon
Perforation
Massive hemorrhage
Venous thromboembolism
Malnutrition
Sepsis

Treatment principles

Hospitalization
Infection assessment
Intravenous corticosteroids

Fluid and electrolyte correction
Thrombosis prophylaxis
Rescue biologic or calcineurin-inhibitor therapy when appropriate
Surgery for deterioration or treatment failure

NPLEX Trap: Severe bloody diarrhea should not be treated with routine antidiarrheal medication.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 83

Perforated Peptic UlcerClinical Case 83

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 58-year-old man develops sudden severe epigastric pain that rapidly spreads throughout the abdomen. History:

Frequent naproxen use
Tobacco use
Previous peptic ulcer disease Vital signs:
BP: 88/52 mmHg
HR: 124/min
Temperature: 38.2°C Physical examination:
Rigid, board-like abdomen
Diffuse guarding
Rebound tenderness
Absent bowel sounds

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Perforated peptic ulcer with peritonitis

Sudden severe pain, rigid abdomen, diffuse peritoneal signs, shock, and NSAID exposure suggest perforation.

Q2

Which imaging finding supports the diagnosis?

AFree intraperitoneal airBEnlarged cardiac silhouetteCPleural effusion onlyDNormal bowel gas patternEIntracranial hemorrhage

Reveal answer and rationale

✓Correct answer: A. Free intraperitoneal air

Free air beneath the diaphragm or on CT indicates perforation of a hollow viscus.

Q3

What is the most appropriate treatment?

AEmergency resuscitation, intravenous antibiotics, acid suppression, and surgical consultationBAntacid and dischargeCOral ironDAbdominal massageEHigh-fibre diet

Reveal answer and rationale

✓Correct answer: A. Emergency resuscitation, intravenous antibiotics, acid suppression, and surgical consultation

Perforation causes chemical and bacterial peritonitis and generally requires urgent surgical management.

Q4

Which intervention should be avoided?

AOral food and medicationBIntravenous accessCBroad antimicrobial therapyDNasogastric decompression when appropriateESurgical assessment

Reveal answer and rationale

✓Correct answer: A. Oral food and medication

The patient should remain fasting because emergency surgery and gastrointestinal decompression may be required.

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Risk factors

NSAIDs
H. pylori
Tobacco use
Previous ulcer disease

Corticosteroid and anticoagulant combinations

Treatment principles

ABC stabilization
Fasting
IV fluids
Antibiotics
Proton-pump inhibitor
Surgical source control
Later H. pylori testing and eradication

NPLEX Trap: Sudden pain relief after severe ulcer pain may indicate perforation rather than recovery.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 84

Pheochromocytoma CrisisClinical Case 84

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 42-year-old woman presents with severe headache, sweating, palpitations, chest pain, and vomiting. Vital signs fluctuate dramatically:

BP: 248/136 mmHg, later 88/54 mmHg
HR: 142/min
Temperature: 38.3°C She has a known adrenal mass and recently received metoclopramide.

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Pheochromocytoma crisis

An adrenal mass with episodic headache, diaphoresis, palpitations, extreme blood-pressure instability, and catecholamine-triggering medication exposure suggests crisis.

Q2

Which initial pharmacologic principle is correct?

AEstablish alpha-adrenergic blockade before beta-blockadeBGive a beta-blocker alone firstCUse ephedraDBegin stimulant medicationERestrict all fluid

Reveal answer and rationale

✓Correct answer: A. Establish alpha-adrenergic blockade before beta-blockade

Unopposed alpha stimulation after isolated beta-blockade can worsen vasoconstriction and hypertension.

Q3

Which test is used for biochemical assessment after stabilization?

Reveal answer and rationale

✓Correct answer: A. Plasma-free or urinary fractionated metanephrines

Metanephrines are sensitive markers of catecholamine-producing tumours.

Q4

What is the definitive treatment?

ASurgical removal after appropriate preoperative preparationBLong-term beta-blocker monotherapyCHerbal adrenal supportDRadiation in every patientEObservation only

Reveal answer and rationale

✓Correct answer: A. Surgical removal after appropriate preoperative preparation

Tumour removal is definitive, but careful alpha blockade, volume preparation, and multidisciplinary planning are required first.

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Potential triggers

Surgery
Anesthesia
Metoclopramide
Glucocorticoids
Certain antidepressants
Stimulants
Tumour manipulation

Clinical Pearl: Blood pressure may alternate between extreme hypertension and shock.

NPLEX Trap: Never begin isolated beta-blockade before adequate alpha blockade.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 85

Myxedema ComaClinical Case 85

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 76-year-old woman with longstanding hypothyroidism is brought in during winter because of progressive confusion and reduced responsiveness. She stopped levothyroxine several months ago. Vital signs:

BP: 82/48 mmHg
HR: 42/min
RR: 8/min
Temperature: 32.8°C Laboratory findings:
Sodium: 119 mmol/L
Glucose: low
TSH: markedly elevated
Free T4: very low
PaCO₂: elevated

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Myxedema coma

Severe hypothyroidism with hypothermia, bradycardia, hypoventilation, hyponatremia, hypotension, and altered consciousness indicates myxedema coma.

Q2

What is the most appropriate treatment?

AIntravenous thyroid hormone, stress-dose glucocorticoid, and supportive critical careBOral levothyroxine at homeCAspirin and dischargeDCooling blanketsEBeta-blocker

Reveal answer and rationale

✓Correct answer: A. Intravenous thyroid hormone, stress-dose glucocorticoid, and supportive critical care

Treatment includes thyroid-hormone replacement, empiric glucocorticoid until adrenal insufficiency is excluded, ventilatory support, glucose correction, and treatment of the precipitant.

Q3

How should hypothermia generally be managed?

AGentle passive rewarmingBAggressive external heating immediatelyCIce-water immersionDAntipyreticsENo temperature monitoring

Reveal answer and rationale

✓Correct answer: A. Gentle passive rewarming

Aggressive peripheral warming may cause vasodilation and worsen cardiovascular instability.

Q4

Which common precipitating factor should be investigated?

Reveal answer and rationale

✓Correct answer: A. Infection

Infection, cold exposure, medication interruption, sedatives, stroke, and cardiac events may precipitate decompensation.

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Treatment principles

Airway and ventilatory support
Intravenous thyroid hormone
Stress-dose corticosteroid
Gentle rewarming
Correct glucose and sodium carefully
Treat infection or another precipitant

NPLEX Trap: The term “coma” is historical; the patient may be severely confused without being fully unconscious.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 86

Guillain-Barré SyndromeClinical Case 86

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 38-year-old man develops tingling in the feet followed by progressive ascending weakness one week after diarrheal illness. Examination:

Symmetric leg weakness
Reduced arm strength
Absent deep-tendon reflexes
Mild facial weakness
Difficulty taking a deep breath

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Guillain-Barré syndrome

Acute ascending symmetric weakness with areflexia after infection is characteristic.

Q2

What is the immediate priority?

AMonitor respiratory function and autonomic statusBBegin exercise therapyCPerform spinal manipulationDDischarge with reassuranceEGive magnesium

Reveal answer and rationale

✓Correct answer: A. Monitor respiratory function and autonomic status

Respiratory failure and autonomic instability may develop rapidly.

Q3

Which treatment is appropriate for significant progressive disease?

AIntravenous immunoglobulin or plasma exchangeBLong-term corticosteroid monotherapyCAntibiotics in every caseDOral ironEAspirin

Reveal answer and rationale

✓Correct answer: A. Intravenous immunoglobulin or plasma exchange

Both treatments can shorten recovery when used appropriately. Corticosteroids alone are not effective standard therapy.

Q4

Which cerebrospinal-fluid pattern is typical?

AElevated protein with relatively few white cellsBLow protein with marked neutrophiliaCRed-cell castsDMalignant cellsEVery low glucose in every case

Reveal answer and rationale

✓Correct answer: A. Elevated protein with relatively few white cells

Albuminocytologic dissociation supports the diagnosis, although early CSF may be normal.

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Potential complications

Respiratory failure
Arrhythmia
Blood-pressure instability
Urinary retention
Venous thrombosis
Neuropathic pain

NPLEX Trap: Normal oxygen saturation does not exclude impending ventilatory failure.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 87

Foodborne BotulismClinical Case 87

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 47-year-old woman develops blurred vision, diplopia, dry mouth, difficulty swallowing, and descending weakness after eating home-canned vegetables. She is alert and afebrile. Examination:

Bilateral ptosis
Dilated poorly reactive pupils
Weak gag reflex
Descending symmetric paralysis

Reduced respiratory effort
Sensation is intact

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Foodborne botulism

Cranial-nerve dysfunction followed by descending flaccid paralysis after home-canned food exposure is characteristic.

Q2

What is the immediate management priority?

ARespiratory monitoring and antitoxin administrationBOral antibiotics onlyCExerciseDSpinal manipulationEInduce vomiting

Reveal answer and rationale

✓Correct answer: A. Respiratory monitoring and antitoxin administration

Antitoxin neutralizes circulating toxin but does not reverse established paralysis. It should be administered promptly based on clinical suspicion.

Q3

Which function is typically preserved?

Reveal answer and rationale

✓Correct answer: A. Sensation

Botulism is primarily a motor and autonomic disorder; sensory examination is usually normal.

Q4

What is the mechanism?

ABlockade of acetylcholine release at presynaptic nerve terminalsBDestruction of dopamine neuronsCExcess serotonin releaseDSodium-channel activationEAntibody-mediated demyelination only

Reveal answer and rationale

✓Correct answer: A. Blockade of acetylcholine release at presynaptic nerve terminals

Botulinum toxin prevents acetylcholine release, causing flaccid paralysis and autonomic dysfunction.

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Key features

Diplopia
Ptosis
Dysarthria
Dysphagia
Dry mouth
Descending weakness
Respiratory failure

NPLEX Trap: The patient may remain fully alert despite profound paralysis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 88

Generalized TetanusClinical Case 88

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 56-year-old gardener develops jaw stiffness, painful muscle spasms, and difficulty swallowing one week after puncturing his foot on a rusty nail. Vaccination history is unknown. Examination:

Trismus
Risus sardonicus
Generalized rigidity
Painful spasms triggered by noise and touch
Autonomic instability

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Generalized tetanus

Trismus, stimulus-induced painful spasms, generalized rigidity, and a contaminated wound suggest tetanus.

Q2

Which therapy neutralizes unbound toxin?

Reveal answer and rationale

✓Correct answer: A. Human tetanus immune globulin

Immune globulin neutralizes toxin that has not yet bound to nerve tissue.

Q3

What additional treatment is required?

AWound debridement and antimicrobial therapyBNo wound careCOral ironDCorticosteroid injection into the woundEMassage therapy

Reveal answer and rationale

✓Correct answer: A. Wound debridement and antimicrobial therapy

Source control reduces ongoing toxin production.

Q4

Does recovery from tetanus provide reliable immunity?

ANo; vaccination is still requiredBYes; no vaccine is neededCOnly in childrenDOnly after severe diseaseEOnly if antibodies are measured

Reveal answer and rationale

✓Correct answer: A. No; vaccination is still required

The amount of toxin causing disease may be too small to generate protective immunity.

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Treatment principles

Airway support
Minimize stimulation
Immune globulin
Wound debridement
Antibiotics
Spasm control
Autonomic management
Vaccination

NPLEX Trap: Rust itself does not cause tetanus; contaminated anaerobic puncture wounds create risk.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 89

Malignant Otitis ExternaClinical Case 89

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 72-year-old man with poorly controlled diabetes presents with severe persistent ear pain, purulent discharge, and headache. The pain is worse at night. Examination:

Granulation tissue in the external auditory canal
Marked canal tenderness
Facial weakness on the affected side

Q1

What is the most likely diagnosis?

ASimple otitis externaBMalignant otitis externa with skull-base osteomyelitisCOtitis media onlyDCerumen impactionETemporomandibular-joint dysfunction

Reveal answer and rationale

✓Correct answer: B. Malignant otitis externa with skull-base osteomyelitis

Severe nocturnal pain, diabetes, granulation tissue, persistent drainage, and cranial-nerve involvement indicate invasive infection.

Q2

Which organism is most commonly associated?

Reveal answer and rationale

✓Correct answer: A. Pseudomonas aeruginosa

Pseudomonas is the classic pathogen, particularly in older adults with diabetes.

Q3

What is the appropriate management?

AUrgent ENT assessment and systemic antipseudomonal treatmentBEar candlingCTopical herbal oil onlyDRoutine follow-up in one monthEForceful irrigation

Reveal answer and rationale

✓Correct answer: A. Urgent ENT assessment and systemic antipseudomonal treatment

The infection may invade bone and cranial nerves, requiring prolonged systemic treatment and imaging.

Q4

Which intervention should be avoided?

AEar candling or unsterile oil instillationBGlucose managementCCulture of drainageDCranial-nerve examinationEImaging assessment

Reveal answer and rationale

✓Correct answer: A. Ear candling or unsterile oil instillation

These measures can worsen injury and delay treatment of an invasive infection.

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Red flags

Severe pain out of proportion
Granulation tissue
Diabetes or immunosuppression
Cranial neuropathy
Failure of routine topical therapy

NPLEX Trap: Facial weakness in apparent otitis externa suggests invasive skull-base disease.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 90

Orbital CellulitisClinical Case 90

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

An 11-year-old child presents with fever, swollen eyelids, severe eye pain, and reduced vision following bacterial sinusitis. Examination:

Proptosis
Painful restricted eye movements

Reduced visual acuity
Relative afferent pupillary defect
Fever and toxic appearance

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Orbital cellulitis

Proptosis, painful ophthalmoplegia, reduced vision, and pupillary abnormality indicate infection behind the orbital septum.

Q2

What is the appropriate management?

AHospitalization, intravenous antibiotics, and urgent ophthalmology and ENT consultationBOral antihistamine and dischargeCWarm compress onlyDTopical steroid aloneEEye patching

Reveal answer and rationale

✓Correct answer: A. Hospitalization, intravenous antibiotics, and urgent ophthalmology and ENT consultation

Orbital cellulitis can cause blindness, cavernous-sinus thrombosis, intracranial infection, and abscess.

Q3

Which imaging study is commonly required?

AContrast-enhanced CT of the orbits and sinusesBRoutine skull radiographCAbdominal ultrasoundDKnee MRIEEchocardiography

Reveal answer and rationale

✓Correct answer: A. Contrast-enhanced CT of the orbits and sinuses

Imaging assesses orbital extension, sinus disease, and abscess formation.

Q4

Which feature distinguishes orbital from preseptal cellulitis?

Reveal answer and rationale

✓Correct answer: A. Painful restricted extraocular movement

Ophthalmoplegia, proptosis, visual impairment, and pupillary changes indicate orbital involvement.

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Potential complications

Vision loss
Subperiosteal abscess
Orbital abscess
Cavernous-sinus thrombosis
Meningitis
Brain abscess

NPLEX Trap: Eyelid swelling with normal vision and painless full eye movement is more consistent with preseptal disease.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 91

Peritonsillar AbscessClinical Case 91

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 24-year-old man presents with severe unilateral sore throat, fever, drooling, and difficulty opening his mouth. Examination:

Muffled “hot-potato” voice
Trismus
Swelling above the right tonsil
Uvula deviated toward the left

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Peritonsillar abscess

Unilateral swelling, uvular deviation, trismus, drooling, and muffled voice are classic.

Q2

What is the appropriate treatment?

Reveal answer and rationale

✓Correct answer: A. Drainage plus antimicrobial therapy

Needle aspiration or incision and drainage is commonly required along with antimicrobial treatment.

Q3

What is the immediate safety priority?

AAssess the airwayBPerform vigorous throat manipulationCEncourage solid foodDDelay treatment for culture resultsEApply external heat only

Reveal answer and rationale

✓Correct answer: A. Assess the airway

Severe swelling, drooling, respiratory symptoms, or inability to handle secretions may signal threatened airway obstruction.

Q4

Which finding suggests spread to a deeper neck space?

ANeck swelling, stiffness, or respiratory distressBMild sore throatCNormal voiceDNormal swallowingEIsolated nasal congestion

Reveal answer and rationale

✓Correct answer: A. Neck swelling, stiffness, or respiratory distress

Deep-neck infection may spread rapidly and compromise the airway or mediastinum.

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Common organisms: Mixed aerobic and anaerobic oral flora.

NPLEX Trap: A muffled voice and uvular deviation indicate more than uncomplicated tonsillitis.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 92

Ludwig AnginaClinical Case 92

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 49-year-old man with a recent infected lower molar presents with fever, neck swelling, drooling, and difficulty swallowing. Examination:

Firm bilateral submandibular swelling
Elevated tongue
Floor of the mouth is tense
Muffled voice
Stridor is beginning

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Ludwig angina

Bilateral cellulitis of the submandibular and sublingual spaces with tongue elevation after dental infection is diagnostic.

Q2

What is the immediate priority?

ASecure the airway with expert assistanceBPerform routine oral examination for several minutesCGive oral fluidsDDelay until CT is completedEBegin throat lozenges

Reveal answer and rationale

✓Correct answer: A. Secure the airway with expert assistance

Airway obstruction can develop rapidly. Airway planning precedes diagnostic imaging when the patient is deteriorating.

Q3

What additional treatment is required?

AIntravenous broad-spectrum antibiotics and dental or surgical source controlBAntihistamine aloneCOral analgesic onlyDHerbal mouthwashEObservation

Reveal answer and rationale

✓Correct answer: A. Intravenous broad-spectrum antibiotics and dental or surgical source control

Treatment must cover oral aerobic and anaerobic flora and address the dental source.

Q4

Which finding is particularly dangerous?

Reveal answer and rationale

✓Correct answer: A. Tongue elevation and stridor

These findings indicate progressive upper-airway obstruction.

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Potential complications

Airway obstruction
Deep-neck abscess
Mediastinitis
Sepsis

NPLEX Trap: Do not send a patient with floor-of-mouth swelling home with oral antibiotics alone.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 93

Kawasaki DiseaseClinical Case 93

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 4-year-old child has had fever for six days. Examination:

Bilateral nonpurulent conjunctival injection
Red cracked lips
Strawberry tongue
Polymorphous rash
Swollen red hands and feet
Enlarged cervical lymph node

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Kawasaki disease

Prolonged fever plus conjunctivitis, oral changes, rash, extremity changes, and cervical lymphadenopathy is classic.

Q2

What is the major feared complication?

Reveal answer and rationale

✓Correct answer: A. Coronary-artery aneurysm

Medium-vessel vasculitis can damage the coronary arteries and cause aneurysm, thrombosis, or myocardial ischemia.

Q3

What is the standard acute treatment?

AIntravenous immunoglobulin and aspirin under specialist careBAntibiotics onlyCCorticosteroid creamDAntihistamine onlyENo treatment

Reveal answer and rationale

✓Correct answer: A. Intravenous immunoglobulin and aspirin under specialist care

Prompt treatment reduces coronary complications. Additional anti-inflammatory therapy may be used in higher-risk disease.

Q4

Which investigation is essential?

Reveal answer and rationale

✓Correct answer: A. Echocardiography

Echocardiography evaluates coronary arteries and cardiac function.

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Diagnostic features

Fever for at least five days
Bilateral conjunctivitis
Oral changes

Rash
Extremity changes
Cervical lymphadenopathy

NPLEX Trap: Aspirin is generally avoided in children, but Kawasaki disease is an important specialist-managed exception.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 94

IntussusceptionClinical Case 94

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 9-month-old infant has intermittent episodes of severe crying, drawing the knees toward the chest, and vomiting. Between episodes, the infant becomes quiet and lethargic. Examination:

Sausage-shaped abdominal mass
Bloody mucus stool described as “currant jelly”

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Intussusception

Intermittent colicky pain, vomiting, lethargy, abdominal mass, and bloody mucus stool are classic.

Q2

Which imaging study is usually first-line?

Reveal answer and rationale

✓Correct answer: A. Abdominal ultrasound

Ultrasound may demonstrate a target or doughnut sign.

Q3

What treatment is commonly both diagnostic and therapeutic in a stable patient without perforation?

Reveal answer and rationale

✓Correct answer: A. Air or contrast enema

Image-guided enema reduction is commonly attempted when there is no perforation, peritonitis, or severe instability.

Q4

Which finding requires surgery rather than enema reduction?

Reveal answer and rationale

✓Correct answer: A. Peritonitis or perforation

Perforation, shock, peritonitis, or failed enema reduction requires surgery.

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Potential lead points

Often idiopathic in infants
Meckel diverticulum
Polyp
Lymphoma
Henoch-Schönlein purpura

NPLEX Trap: The complete classic triad is not present in every child.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 95

Hypertrophic Pyloric StenosisClinical Case 95

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 5-week-old infant presents with progressive forceful vomiting after feeding.

The vomit is nonbilious. The infant remains hungry after vomiting. Examination:

Dehydration
Visible gastric peristalsis
Small firm “olive” mass in the upper abdomen Laboratory findings:
Hypochloremic metabolic alkalosis
Low potassium

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Hypertrophic pyloric stenosis

Progressive projectile nonbilious vomiting, persistent hunger, an olive-like mass, and metabolic alkalosis are classic.

Q2

Which investigation confirms the diagnosis?

Reveal answer and rationale

✓Correct answer: A. Abdominal ultrasound

Ultrasound demonstrates thickening and elongation of the pyloric muscle.

Q3

What must occur before surgery?

ACorrect dehydration and electrolyte abnormalitiesBImmediate feedingCGive a stimulant laxativeDBegin antibiotics in every caseENo stabilization is required

Reveal answer and rationale

✓Correct answer: A. Correct dehydration and electrolyte abnormalities

Pyloric stenosis is a medical stabilization problem before it becomes a surgical correction problem.

Q4

What is the definitive treatment?

Reveal answer and rationale

✓Correct answer: A. Pyloromyotomy

Surgical division of the hypertrophied pyloric muscle relieves the obstruction.

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Clinical Pearl: Bilious vomiting suggests obstruction distal to the stomach and is not typical of pyloric stenosis.

NPLEX Trap: Do not rush to surgery before correcting significant alkalosis and dehydration.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 96

Postpartum EndometritisClinical Case 96

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 30-year-old woman develops fever, lower abdominal pain, and foul-smelling lochia three days after cesarean delivery. Vital signs:

BP: 102/64 mmHg
HR: 116/min
Temperature: 39.0°C Examination:
Uterine tenderness
Foul vaginal discharge
Incision appears intact

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Postpartum endometritis

Postpartum fever, uterine tenderness, pelvic pain, and foul lochia after cesarean delivery indicate uterine infection.

Q2

What is the appropriate treatment?

Reveal answer and rationale

✓Correct answer: A. Broad-spectrum intravenous antibiotics

Treatment must cover mixed aerobic and anaerobic genital-tract organisms.

Q3

Which risk factor is strongest in this case?

Reveal answer and rationale

✓Correct answer: A. Cesarean delivery

Cesarean birth substantially increases postpartum endometritis risk compared with uncomplicated vaginal delivery.

Q4

Which complication should be considered if fever persists despite appropriate therapy?

ARetained products, pelvic abscess, or septic pelvic thrombophlebitisBSeasonal allergyCMigraineDAsthmaEIron deficiency only

Reveal answer and rationale

✓Correct answer: A. Retained products, pelvic abscess, or septic pelvic thrombophlebitis

Persistent fever requires reassessment for inadequate source control or another infectious process.

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Treatment principles

Intravenous antibiotics
Blood cultures in severe illness
Ultrasound when retained tissue is suspected
Sepsis management when unstable

NPLEX Trap: Postpartum fever with uterine tenderness is not normal postpartum recovery.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 97

Ovarian Hyperstimulation SyndromeClinical Case 97

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 33-year-old woman undergoing fertility treatment presents with abdominal distension, nausea, shortness of breath, and reduced urine output. Examination:

Enlarged tender ovaries
Ascites
Rapid weight gain
Bilateral pleural effusions Laboratory findings:
Hematocrit: elevated
Creatinine: increased
Sodium: low
Albumin: low

Q1

What is the most likely diagnosis?

AEctopic pregnancyBOvarian hyperstimulation syndromeCPelvic inflammatory diseaseDSimple ovarian cystENormal medication response

Reveal answer and rationale

✓Correct answer: B. Ovarian hyperstimulation syndrome

Fertility treatment followed by enlarged ovaries, third spacing, hemoconcentration, ascites, pleural effusion, and kidney dysfunction is characteristic.

Q2

What causes the fluid shift?

AIncreased vascular permeabilityBSevere dehydration from sweating onlyCReduced insulin secretionDPrimary heart-valve failureEExcess thyroid hormone

Reveal answer and rationale

✓Correct answer: A. Increased vascular permeability

Vasoactive mediators increase capillary permeability, moving fluid into the abdomen and pleural spaces.

Q3

Which complication is particularly important?

Reveal answer and rationale

✓Correct answer: A. Venous thromboembolism

Hemoconcentration and reduced mobility increase thrombosis risk.

Q4

What is the appropriate management for severe disease?

AHospital monitoring, careful fluid management, thrombosis assessment, and fertility-specialist careBRoutine exerciseCHerbal diuretic therapyDFluid restriction without assessmentEOutpatient massage

Reveal answer and rationale

✓Correct answer: A. Hospital monitoring, careful fluid management, thrombosis assessment, and fertility-specialist care

Severe disease may cause respiratory compromise, kidney injury, thrombosis, and ovarian complications.

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NPLEX Trap: Apparent edema and ascites coexist with reduced effective circulating volume, so indiscriminate diuretic use can worsen perfusion.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 98

Ischemic PriapismClinical Case 98

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 27-year-old man with sickle cell disease presents with a painful erection lasting six hours without sexual stimulation. Examination:

Rigid corpora cavernosa
Soft glans
Severe penile pain

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Ischemic priapism

A prolonged painful rigid erection with a soft glans indicates low-flow ischemic priapism.

Q2

What is the appropriate action?

AEmergency urologic managementBObserve for 24 hoursCApply a tight constriction bandDBegin an oral herbal aphrodisiacEExercise vigorously

Reveal answer and rationale

✓Correct answer: A. Emergency urologic management

Ischemic priapism is a compartment-like emergency that can cause permanent erectile dysfunction.

Q3

What is the standard initial procedural treatment?

ACorporal aspiration and irrigation with intracavernosal sympathomimetic therapyBCircumcisionCVasectomyDProstate massageEBladder catheterization only

Reveal answer and rationale

✓Correct answer: A. Corporal aspiration and irrigation with intracavernosal sympathomimetic therapy

Aspiration reduces pressure and removes hypoxic blood; phenylephrine is commonly used under monitoring.

Q4

Which medication history is relevant?

Reveal answer and rationale

✓Correct answer: A. Trazodone or antipsychotic use

Several medications can precipitate priapism through adrenergic blockade or vascular effects.

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Potential causes

Sickle cell disease
Medications
Leukemia
Pelvic malignancy
Intracavernosal medication
Idiopathic disease

NPLEX Trap: A painful erection lasting longer than four hours is an emergency, not a condition for watchful waiting.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 99

Disseminated Intravascular CoagulationClinical Case 99

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 63-year-old woman with septic shock develops bleeding from IV sites, widespread bruising, and reduced urine output. Laboratory findings:

Platelets: 32 × 10⁹/L
PT and aPTT: prolonged
Fibrinogen: low
D-dimer: markedly elevated
Schistocytes on blood smear

Q1

What is the most likely diagnosis?

Reveal answer and rationale

✓Correct answer: B. Disseminated intravascular coagulation

Consumptive thrombocytopenia, prolonged clotting times, low fibrinogen, elevated fibrin degradation products, and bleeding in severe sepsis indicate DIC.

Q2

What is the treatment priority?

Reveal answer and rationale

✓Correct answer: A. Treat the underlying cause

DIC is secondary to another severe disorder, such as sepsis, trauma, malignancy, or obstetric catastrophe.

Q3

When are blood products generally used?

ASignificant bleeding or high-risk procedures with documented deficiencyBIn every patient regardless of bleedingCNeverDOnly after dischargeEFor mild bruising alone

Reveal answer and rationale

✓Correct answer: A. Significant bleeding or high-risk procedures with documented deficiency

Platelets, plasma, cryoprecipitate, or fibrinogen replacement are individualized based on bleeding and laboratory abnormalities.

Q4

Which process occurs simultaneously in DIC?

APathologic clot formation and bleedingBOnly bleedingCOnly arterial vasodilationDOnly platelet overproductionEOnly hemolysis

Reveal answer and rationale

✓Correct answer: A. Pathologic clot formation and bleeding

Widespread coagulation activation causes microvascular thrombosis while consuming platelets and clotting factors.

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Common causes

Sepsis
Placental abruption
Amniotic-fluid embolism
Major trauma

Malignancy
Severe transfusion reaction

NPLEX Trap: DIC can cause thrombosis and organ ischemia even when external bleeding is prominent.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

NPLEX Part II • Phase 1 • Clinical Case 100

Febrile NeutropeniaClinical Case 100

4 questions•Answers + rationales•Disease overview + exam traps

Case Presentation

A 55-year-old woman receiving chemotherapy for acute leukemia presents with chills and weakness. Vital signs:

BP: 88/54 mmHg
HR: 124/min
Temperature: 38.5°C
RR: 24/min Laboratory findings:
Absolute neutrophil count: 0.2 × 10⁹/L
Lactate: elevated
Creatinine: increased She has no obvious localizing symptoms.

Q1

What is the most likely diagnosis?

AUncomplicated viral illnessBHigh-risk febrile neutropenia with sepsisCMedication-induced fever onlyDStable chemotherapy effectEAllergic reaction

Reveal answer and rationale

✓Correct answer: B. High-risk febrile neutropenia with sepsis

Fever with profound neutropenia, hypotension, elevated lactate, and kidney dysfunction indicates a life-threatening infection even without localizing signs.

Q2

What is the most appropriate management?

AImmediate broad-spectrum intravenous antipseudomonal antibiotics and sepsis resuscitationBWait for culture resultsCOral antibiotics at homeDHerbal immune stimulantEAntipyretic only

Reveal answer and rationale

✓Correct answer: A. Immediate broad-spectrum intravenous antipseudomonal antibiotics and sepsis resuscitation

Treatment must begin urgently because neutropenic patients can deteriorate rapidly and may not produce typical inflammatory findings.

Q3

Which cultures should be obtained when feasible without delaying treatment?

ABlood cultures from peripheral and central-line sites when presentBStool culture onlyCSkin scraping onlyDNo culturesEThroat culture only

Reveal answer and rationale

✓Correct answer: A. Blood cultures from peripheral and central-line sites when present

Multiple cultures improve identification of bloodstream and catheter-related infection.

Q4

Which examination finding may be absent despite serious infection?

Reveal answer and rationale

✓Correct answer: A. Pus or marked local inflammation

Profound neutropenia limits the ability to form pus and may produce deceptively subtle examination findings.

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High-risk features

Profound or prolonged neutropenia
Hypotension
Organ dysfunction
Pneumonia
Abdominal symptoms
Neurologic change
Significant comorbidity
Hematologic malignancy

Treatment principles

Immediate cultures
Broad antipseudomonal antibiotics

Fluid and vasopressor resuscitation
Source assessment
Central-line evaluation
Antifungal assessment when fever persists
Protective infection-prevention measures

Botanical safety: Immune-stimulating supplements may interact with chemotherapy and must not delay antimicrobial treatment.

Clinical Pearl: Serious infection may be present without redness, swelling, or pus.

NPLEX Trap: Do not wait for the absolute neutrophil count to fall below zero or for cultures to become positive before treating.

Educational exam-preparation content. Emergency findings in these cases require urgent medical assessment and should not be managed solely with complementary care.

Hemoglobin	Female 120–160 g/L; Male 135–175 g/L
Hematocrit	Female 0.36–0.46; Male 0.40–0.52
WBC count	4.0–11.0 × 10⁹/L
Platelets	150–400 × 10⁹/L
MCV	80–100 fL
Reticulocytes	0.5–2.5%
PT / INR	INR 0.8–1.2 when not anticoagulated
aPTT	Approximately 25–35 seconds

Sodium	135–145 mmol/L
Potassium	3.5–5.0 mmol/L
Chloride	98–106 mmol/L
Bicarbonate	22–29 mmol/L
Urea / BUN	Urea 2.5–7.1 mmol/L
Creatinine	Female ~45–90 µmol/L; Male ~60–110 µmol/L
Serum osmolality	275–295 mOsm/kg
Urine specific gravity	1.005–1.030

Fasting glucose	3.9–5.5 mmol/L
Calcium, total	2.15–2.55 mmol/L
Magnesium	0.70–1.00 mmol/L
Phosphate	0.80–1.50 mmol/L
TSH	Approximately 0.4–4.0 mIU/L
Free T4	Approximately 10–23 pmol/L
Morning cortisol	Assay- and time-dependent; interpret with local range
HbA1c	Normal <5.7% (<39 mmol/mol)

AST	Approximately 10–40 U/L
ALT	Approximately 7–56 U/L
Alkaline phosphatase	Approximately 40–130 U/L
Total bilirubin	3–21 µmol/L
Albumin	35–50 g/L
GGT	Assay- and sex-dependent
Lipase	Assay-dependent; pancreatitis often ≥3× upper limit
Ammonia	Assay- and specimen-handling dependent

pH	7.35–7.45
PaCO₂	35–45 mm Hg
PaO₂	80–100 mm Hg at sea level
HCO₃⁻	22–26 mmol/L
Base excess	−2 to +2 mmol/L
Lactate	Approximately 0.5–2.0 mmol/L
Oxygen saturation	Usually 95–100%

CSF opening pressure	Approximately 10–20 cm H₂O
CSF WBC	0–5 cells/µL
CSF protein	0.15–0.45 g/L
CSF glucose	~60–70% of simultaneous serum glucose
Glucose conversion	mg/dL ÷ 18 = mmol/L
Creatinine conversion	mg/dL × 88.4 = µmol/L
Bilirubin conversion	mg/dL × 17.1 = µmol/L
Calcium conversion	mg/dL × 0.25 = mmol/L

No matching content found

Case Presentation

What is the most likely diagnosis?

What is the most appropriate immediate action?

Which medication is generally administered early when acute coronary syndrome is suspected and no contraindication is present?

The patient reports taking high-dose garlic extract and ginkgo. What is the most important concern?

Disease Review & Exam Traps

Key differentials

Key investigations

Treatment principles

Nutrition and lifestyle after stabilization

Case Presentation

What is the most likely diagnosis?

What is the most appropriate immediate management?

Which finding suggests impending respiratory failure?

Which botanical product is most concerning in this patient because of additive sympathomimetic effects?

Disease Review & Exam Traps

Key differentials

Key assessments

Treatment principles

Long-term management

Nutrition and lifestyle

Case Presentation

What is the most likely diagnosis?

What is the most appropriate initial treatment priority?

Why can the initial serum potassium be elevated despite a total-body potassium deficit?

Which statement represents appropriate sick-day counseling?

Disease Review & Exam Traps

Common triggers

Key investigations

Treatment principles

Case Presentation

What is the most likely diagnosis?

What is the first-line medication?

What is the best response if symptoms persist after the initial epinephrine dose?

Which medication may reduce the response to epinephrine and complicate anaphylaxis treatment?

Disease Review & Exam Traps

Potential triggers

Clinical features

Treatment principles

Nutrition and prevention

Case Presentation

What is the most likely diagnosis?

What is the most appropriate immediate management?

Which finding best indicates acute organ dysfunction?

Which statement regarding cranberry is most appropriate?

Disease Review & Exam Traps

Key differentials

Key investigations

Treatment principles

Case Presentation

What is the most likely diagnosis?

What is the most appropriate immediate action?

What is the priority brain investigation?

Which supplement is especially important to document because of potential bleeding concerns?

Disease Review & Exam Traps

Key differentials

Key investigations

Treatment principles

Nutrition and rehabilitation

Case Presentation

What is the most likely diagnosis?

What is the immediate management priority?

Which medication most likely contributed to the underlying mucosal injury?

Which botanical supplement would raise additional concern regarding bleeding?

Disease Review & Exam Traps

Key differentials

Key investigations

Treatment principles

Case Presentation

What is the most likely diagnosis?

What is the most appropriate next step?

Which investigation is central to evaluation in a stable patient with suspected ectopic pregnancy?

Which treatment would be inappropriate in this unstable patient?

Disease Review & Exam Traps

Key differentials

Key investigations

Treatment principles

Case Presentation

What is the most likely diagnosis?