Laboratory & Imaging Diagnosis

1

Clinical Case Cluster 1

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 38-year-old patient presents with progressive fatigue, exertional dyspnea, headaches and a craving for ice. Menstrual periods last 8–9 days and require changing a saturated pad every 1–2 hours during the first 3 days. There is no melena, hematochezia or abdominal pain. Physical examination shows conjunctival pallor and brittle nails. Test Result Hemoglobin 9.1 g/dL Hematocrit 29% MCV 69 fL MCHC Decreased RDW 18.9% Platelets 468 × 10⁹/L WBC 7.2 × 10⁹/L

Question 1 of 4NPLEX-LAB-001

Diagnosis Foundational

Which diagnosis best explains the CBC pattern?

A Vitamin B12 deficiency B Iron-deficiency anemia C Beta-thalassemia trait D Anemia of chronic inflammation

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Question 2 of 4NPLEX-LAB-002

Test selection and interpretation Intermediate

Which test is most appropriate to confirm depleted iron stores?

A Direct antiglobulin test B Haptoglobin C Serum ferritin D Serum folate

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Question 3 of 4NPLEX-LAB-003

Test selection and interpretation Intermediate

Which additional iron-study pattern is most likely?

A High iron, low TIBC, high transferrin saturation B Low iron, low TIBC, high transferrin saturation C High iron, high TIBC, low transferrin saturation D Low iron, high TIBC, low transferrin saturation

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Question 4 of 4NPLEX-LAB-004

Clinical application Intermediate–advanced

What is the most appropriate next clinical step?

A Begin iron replacement and evaluate the uterine bleeding B Arrange immediate bone-marrow transplantation assessment C Reassure the patient that the thrombocytosis is malignant D Begin folic acid without further investigation

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2

Clinical Case Cluster 2

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 67-year-old patient reports fatigue, tongue soreness, numbness of both feet and increasing difficulty walking in the dark. The patient has autoimmune thyroid disease and eats a mixed diet. Examination shows glossitis, reduced vibration sensation and an unsteady gait. Test Result Hemoglobin 9.8 g/dL MCV 113 fL WBC 3.3 × 10⁹/L Platelets 118 × 10⁹/L Vitamin B12 Borderline low Folate Normal The peripheral smear demonstrates macro-ovalocytes and hypersegmented neutrophils.

Question 1 of 4NPLEX-LAB-005

Diagnosis Foundational

Which diagnosis is most likely?

A Alpha-thalassemia trait B Vitamin B12–deficiency megaloblastic anemia C Acute blood-loss anemia D Iron-deficiency anemia

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Question 2 of 4NPLEX-LAB-006

Test selection and interpretation Intermediate

Which test is most useful when the vitamin B12 result is indeterminate?

A D-dimer B Haptoglobin C Serum ferritin D Methylmalonic acid

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Question 3 of 4NPLEX-LAB-007

Test selection and interpretation Intermediate

Which test would best evaluate the suspected cause in this patient?

A Anti-intrinsic-factor antibody B Antinuclear antibody C Direct antiglobulin test D Hemoglobin electrophoresis

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Question 4 of 4NPLEX-LAB-008

Clinical application Intermediate–advanced

What is the most appropriate immediate management principle?

A Give folate alone until testing is complete B Delay treatment until bone-marrow biopsy C Begin vitamin B12 replacement promptly D Treat initially with oral iron alone

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3

Clinical Case Cluster 3

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 29-year-old patient with systemic lupus erythematosus presents with worsening fatigue, jaundice, dark urine and shortness of breath. Test Result Hemoglobin 8.2 g/dL MCV 98 fL Reticulocytes 9.4% LDH Elevated Indirect bilirubin Elevated Haptoglobin Undetectable Platelets 212 × 10⁹/L The peripheral smear shows polychromasia and spherocytes.

Question 1 of 4NPLEX-LAB-009

Diagnosis Foundational

Which process best explains these findings?

A Impaired DNA synthesis B Reduced erythropoietin production C Increased red-cell destruction D Reduced iron absorption

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Question 2 of 4NPLEX-LAB-010

Test selection and interpretation Intermediate

Which test best determines whether the hemolysis is immune mediated?

A Serum ferritin B Direct antiglobulin test C Prothrombin time D Hemoglobin A1c

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Question 3 of 4NPLEX-LAB-011

Test selection and interpretation Intermediate

Why is the MCV near the upper end of normal?

A Bilirubin directly enlarges erythrocytes B Spherocytes contain excess nuclear material C Haptoglobin causes erythrocyte swelling D Reticulocytes are larger than mature erythrocytes

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Question 4 of 4NPLEX-LAB-012

Clinical application Intermediate–advanced

The patient has a heart rate of 118/min and dyspnea at rest. What is the best next step?

A Arrange urgent hospital and hematology assessment B Reassure the patient that hemolysis is self-limited C Repeat the CBC in three months D Begin iron replacement without referral

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4

Clinical Case Cluster 4

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 72-year-old patient presents with fatigue, spontaneous bruising, recurrent oral ulcers and two recent respiratory infections. There is no current chemotherapy use. Test Result Hemoglobin 8.4 g/dL MCV 103 fL WBC 2.0 × 10⁹/L Absolute neutrophil count 0.4 × 10⁹/L Platelets 48 × 10⁹/L Reticulocyte count Decreased

Question 1 of 4NPLEX-LAB-013

Diagnosis Foundational

Which term best describes the CBC?

A Pancytopenia B Erythrocytosis C Reactive leukocytosis D Isolated thrombocytopenia

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Question 2 of 4NPLEX-LAB-014

Test selection and interpretation Intermediate

Which initial investigation is most appropriate?

A D-dimer without repeating the blood count B Fasting glucose and hemoglobin A1c C Serum lipase and abdominal radiograph D Repeat CBC with differential and peripheral smear

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Question 3 of 4NPLEX-LAB-015

Test selection and interpretation Intermediate

The smear demonstrates circulating blasts and dysplastic neutrophils. Which test is most likely to establish the diagnosis?

A Oral glucose-tolerance testing B Fecal occult-blood testing C Bone-marrow aspiration and biopsy D Serum ferritin alone

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Question 4 of 4NPLEX-LAB-016

Clinical application Intermediate–advanced

The patient develops a temperature of 38.4°C. What is the best action?

A Routine review after one month B Emergency assessment for neutropenic infection C Repeat the temperature the following day D Begin oral iron and observe

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5

Clinical Case Cluster 5

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 76-year-old patient taking warfarin for atrial fibrillation presents with melena, dizziness and weakness. Trimethoprim-sulfamethoxazole was started 5 days ago. Test Result Hemoglobin 8.1 g/dL Platelets 224 × 10⁹/L PT Markedly prolonged INR 7.2 aPTT Mildly prolonged Creatinine Normal Blood pressure is 92/58 mm Hg.

Question 1 of 4NPLEX-LAB-017

Diagnosis Foundational

Which test is primarily used to monitor warfarin therapy?

A Thrombin time B Platelet-function analysis C Bleeding time D PT expressed as INR

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Question 2 of 4NPLEX-LAB-018

Test selection and interpretation Intermediate

How should the findings be classified?

A Isolated platelet dysfunction B Major bleeding with excessive anticoagulation C Congenital factor VIII deficiency D Therapeutic anticoagulation without bleeding

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Question 3 of 4NPLEX-LAB-019

Test selection and interpretation Intermediate

What is the most appropriate next step?

A Begin oral iron without changing anticoagulation B Add aspirin and arrange outpatient endoscopy C Emergency transfer for reversal and hemorrhage management D Continue warfarin and repeat INR next month

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Question 4 of 4NPLEX-LAB-020

Clinical application Intermediate–advanced

Which factor most likely contributed to the elevated INR?

A Recent interacting antimicrobial therapy B Elevated serum ferritin C Increased dietary vitamin K intake D Isolated thrombocytosis

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6

Clinical Case Cluster 6

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 63-year-old patient is hospitalized with septic shock secondary to pneumonia. The patient develops bleeding from venipuncture sites, widespread ecchymoses and reduced urine output. Test Result Platelets 39 × 10⁹/L PT Prolonged aPTT Prolonged Fibrinogen Decreased D-dimer Markedly elevated Hemoglobin Decreasing Smear Occasional schistocytes

Question 1 of 4NPLEX-LAB-021

Diagnosis Foundational

Which diagnosis best explains the laboratory pattern?

A Disseminated intravascular coagulation B Hemophilia A C Immune thrombocytopenia D Vitamin B12 deficiency

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Question 2 of 4NPLEX-LAB-022

Test selection and interpretation Intermediate

Which finding most strongly distinguishes DIC from isolated immune thrombocytopenia?

A Mucocutaneous bleeding B Reduced platelet count C Presence of ecchymoses D Prolonged PT with decreased fibrinogen

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Question 3 of 4NPLEX-LAB-023

Test selection and interpretation Intermediate

What is the central management principle?

A Treat only the low platelet count B Treat the underlying sepsis while providing supportive care C Delay treatment until every coagulation study normalizes D Begin oral iron as the primary intervention

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Question 4 of 4NPLEX-LAB-024

Clinical application Intermediate–advanced

Which laboratory set is most useful for monitoring progression?

A Ferritin, B12 and folate B TSH, free T4 and thyroid antibodies C Platelets, PT, aPTT, fibrinogen and D-dimer D Lipase, amylase and fecal elastase

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7

Clinical Case Cluster 7

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 70-year-old patient taking escitalopram presents with nausea, headache, confusion and unsteadiness. Examination suggests euvolemia. Test Result Sodium 118 mmol/L Potassium 4.1 mmol/L Glucose Normal Serum osmolality 258 mOsm/kg Urine osmolality 510 mOsm/kg Urine sodium 52 mmol/L TSH Normal Morning cortisol Normal

Question 1 of 4NPLEX-LAB-025

Diagnosis Foundational

How should the sodium disorder be classified?

A Hypotonic hyponatremia B Hypertonic hyponatremia C Isotonic pseudohyponatremia D Hypernatremic dehydration

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Question 2 of 4NPLEX-LAB-026

Test selection and interpretation Intermediate

Which diagnosis best fits the overall pattern?

A Primary hyperaldosteronism B Syndrome of inappropriate antidiuresis C Diabetes insipidus D Osmotic diuresis from hyperglycemia

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Question 3 of 4NPLEX-LAB-027

Test selection and interpretation Intermediate

What is the most appropriate next step?

A Routine dietary counseling alone B Encourage unrestricted free-water intake C Repeat sodium in six months D Emergency monitored treatment

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Question 4 of 4NPLEX-LAB-028

Clinical application Intermediate–advanced

Which complication is associated with overly rapid correction?

A Disseminated intravascular coagulation B Acute hemolytic anemia C Osmotic demyelination syndrome D Iron-overload cardiomyopathy

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8

Clinical Case Cluster 8

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 65-year-old patient with chronic kidney disease takes lisinopril and spironolactone. Routine testing reports potassium of 6.5 mmol/L, but the laboratory marks the sample as significantly hemolyzed. The patient reports mild weakness.

Question 1 of 4NPLEX-LAB-029

Diagnosis Foundational

What is the most appropriate initial response?

A Ignore the result because the sample was hemolyzed B Repeat the potassium at the next annual examination C Obtain an urgent repeat potassium and ECG D Diagnose primary hyperaldosteronism

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Question 2 of 4NPLEX-LAB-030

Test selection and interpretation Intermediate

Which intervention has the most immediate cardiac-stabilizing effect?

A Oral iron replacement B Intravenous calcium C Dietary potassium restriction D Oral sodium bicarbonate alone

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Question 3 of 4NPLEX-LAB-031

Test selection and interpretation Intermediate

What is the principal effect of insulin with glucose in hyperkalemia?

A It shifts potassium into cells B It removes potassium through the bowel C It increases intestinal potassium absorption D It directly replaces calcium

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Question 4 of 4NPLEX-LAB-032

Clinical application Intermediate–advanced

The patient becomes oliguric and potassium remains elevated despite temporizing treatment. Which intervention provides definitive potassium removal?

A Insulin alone B Continuous ECG monitoring alone C Intravenous calcium alone D Urgent dialysis

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9

Clinical Case Cluster 9

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 62-year-old patient presents after 4 days of vomiting and diarrhea. Medications include losartan and frequent ibuprofen use. Test Current Baseline Creatinine 2.1 mg/dL 0.9 mg/dL BUN 46 mg/dL 14 mg/dL Sodium 137 mmol/L 139 mmol/L Potassium 5.1 mmol/L 4.3 mmol/L Urinalysis is bland. Urine specific gravity is elevated, and urine sodium is 12 mmol/L.

Question 1 of 4NPLEX-LAB-033

Diagnosis Foundational

Which mechanism most likely explains the kidney injury?

A Immune-complex glomerulonephritis B Postrenal obstruction C Chronic nephrotic syndrome D Reduced renal perfusion

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Question 2 of 4NPLEX-LAB-034

Test selection and interpretation Intermediate

What is the most appropriate initial management?

A Restore volume and stop contributing nephrotoxic medications B Restrict all fluid despite volume depletion C Begin long-term dialysis without reassessment D Continue ibuprofen to improve renal perfusion

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Question 3 of 4NPLEX-LAB-035

Test selection and interpretation Intermediate

Which finding would instead suggest glomerular injury?

A Low urine sodium after volume loss B Improvement after volume restoration C Dysmorphic erythrocytes and red-cell casts D Bland sediment and concentrated urine

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Question 4 of 4NPLEX-LAB-036

Clinical application Intermediate–advanced

How should the persistent findings be classified?

A Acute kidney injury without CKD B Chronic kidney disease G3aA2 C Chronic kidney disease G1A1 D Nephrotic-range proteinuria

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10

Clinical Case Cluster 10

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 55-year-old patient presents with right-upper-quadrant discomfort, jaundice, dark urine, pale stools and generalized pruritus. Test Result AST 88 U/L ALT 102 U/L Alkaline 642 U/L phosphatase GGT 410 U/L Total bilirubin 5.4 mg/dL Direct bilirubin 4.6 mg/dL Albumin 4.0 g/dL INR 1.0

Question 1 of 4NPLEX-LAB-037

Diagnosis Foundational

Which liver-test pattern is present?

A Predominantly hepatocellular injury B Isolated unconjugated hyperbilirubinemia C Isolated synthetic failure D Cholestatic injury

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Question 2 of 4NPLEX-LAB-038

Test selection and interpretation Intermediate

Which investigation is most appropriate initially?

A Right-upper-quadrant ultrasonography B Pulmonary-function testing C Bone-marrow biopsy D Electroencephalography

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Question 3 of 4NPLEX-LAB-039

Test selection and interpretation Intermediate

Which tests most directly help assess hepatic synthetic function?

A Alkaline phosphatase and GGT B Albumin and PT/INR C Amylase and lipase D AST and ALT

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Question 4 of 4NPLEX-LAB-040

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Routine follow-up after three months B Reassure the patient that the findings are physiologic C Emergency hospital referral for suspected ascending cholangitis D Begin oral iron and repeat bilirubin annually

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11

Clinical Case Cluster 11

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 44-year-old patient presents with fatigue, constipation, cold intolerance, dry skin and an 8-kg weight gain over the past year. Examination shows bradycardia, delayed relaxation of the ankle reflexes and a mildly enlarged, firm thyroid gland. Test Result TSH 18.6 mIU/L Free T4 0.5 ng/dL Hemoglobin 11.4 g/dL Sodium 134 mmol/L LDL cholesterol Elevated

Question 1 of 4NPLEX-LAB-041

Diagnosis Foundational

Which diagnosis best explains the thyroid results?

A Subclinical hyperthyroidism B Central hypothyroidism C Primary hypothyroidism D Euthyroid sick syndrome

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Question 2 of 4NPLEX-LAB-042

Test selection and interpretation Intermediate

Which test best supports autoimmune thyroiditis as the underlying cause?

A Calcitonin B TSH-receptor antibody C Serum thyroglobulin alone D Thyroid peroxidase antibody

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Question 3 of 4NPLEX-LAB-043

Test selection and interpretation Intermediate

After levothyroxine is initiated, when should TSH usually be reassessed following a dose change?

A Approximately 6–8 weeks later B The following morning C Only when symptoms recur D After one year

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Question 4 of 4NPLEX-LAB-044

Clinical application Intermediate–advanced

Which development requires immediate emergency referral?

A Mild constipation B Hypothermia, bradycardia and altered consciousness C Mildly elevated LDL cholesterol D Gradual weight gain

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12

Clinical Case Cluster 12

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 27-year-old patient presents with palpitations, heat intolerance, frequent bowel movements, anxiety and unintentional weight loss. Examination shows a diffuse goitre, fine tremor, lid retraction and mild proptosis. Test Result TSH <0.01 mIU/L Free T4 Elevated Free T3 Elevated ECG Sinus tachycardia

Question 1 of 4NPLEX-LAB-045

Diagnosis Foundational

Which diagnosis is most likely?

A Graves disease B Central hyperthyroidism C Subacute thyroiditis D Toxic multinodular goitre

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Question 2 of 4NPLEX-LAB-046

Test selection and interpretation Intermediate

Which laboratory test most specifically supports Graves disease?

A Thyroid peroxidase antibody alone B Parathyroid hormone C TSH-receptor antibody D Serum calcitonin

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Question 3 of 4NPLEX-LAB-047

Test selection and interpretation Intermediate

The patient is found to be pregnant. Which investigation should be avoided?

A TSH-receptor antibody testing B Radioactive iodine uptake scanning C Repeat free T4 measurement D Thyroid ultrasonography

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Question 4 of 4NPLEX-LAB-048

Clinical application Intermediate–advanced

The patient later develops a temperature of 40°C, severe agitation, vomiting and atrial fibrillation with a ventricular rate of 170/min. What is the best next step?

A Repeat the thyroid tests in six weeks B Routine outpatient follow-up C Begin dietary iodine without referral D Emergency transfer for suspected thyroid storm

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13

Clinical Case Cluster 13

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 35-year-old patient reports progressive fatigue, weight loss, nausea and salt craving. Examination shows postural hypotension and hyperpigmentation of the palmar creases. Test Result Sodium 126 mmol/L Potassium 5.8 mmol/L Glucose 61 mg/dL 8 a.m. cortisol Markedly low ACTH Markedly elevated

Question 1 of 4NPLEX-LAB-049

Diagnosis Foundational

Which diagnosis best explains the findings?

A Secondary adrenal insufficiency B Primary adrenal insufficiency C Primary hyperaldosteronism D Cushing syndrome

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Question 2 of 4NPLEX-LAB-050

Test selection and interpretation Intermediate

Which dynamic test is commonly used to assess adrenal cortisol reserve?

A Dexamethasone suppression test B Oral glucose-tolerance test C Cosyntropin stimulation test D Water-deprivation test

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Question 3 of 4NPLEX-LAB-051

Test selection and interpretation Intermediate

Which renin and aldosterone pattern is most likely?

A Low renin and high aldosterone B Low renin and low ACTH C High aldosterone and low potassium D High renin and low aldosterone

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Question 4 of 4NPLEX-LAB-052

Clinical application Intermediate–advanced

The patient develops vomiting, severe hypotension and confusion. What is the most appropriate management?

A Administer emergency glucocorticoids and isotonic saline B Restrict intravenous fluids C Give oral thyroid hormone alone D Delay treatment until the cosyntropin test is completed

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14

Clinical Case Cluster 14

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 28-year-old patient presents with fatigue, photosensitive facial rash, oral ulcers, joint pain and ankle edema. Blood pressure is 154/96 mm Hg. Test Result ANA Positive Anti-dsDNA Markedly elevated C3 and C4 Decreased Creatinine Increasing Urinalysis Blood 3+, protein 3+ Microscopy Dysmorphic RBCs and RBC casts

Question 1 of 4NPLEX-LAB-053

Diagnosis Foundational

Which complication is most likely?

A Diabetic nephropathy B Lupus nephritis C Nephrolithiasis D Lower urinary-tract infection

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Question 2 of 4NPLEX-LAB-054

Test selection and interpretation Intermediate

Which antibody is relatively specific for systemic lupus erythematosus and may correlate with renal activity?

A Anti-double-stranded DNA antibody B Anti-centromere antibody C Antimitochondrial antibody D Rheumatoid factor

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Question 3 of 4NPLEX-LAB-055

Test selection and interpretation Intermediate

Which laboratory trend most strongly suggests increasing lupus activity?

A Falling anti-dsDNA with rising complement B Isolated elevation of alkaline phosphatase C Rising anti-dsDNA with falling complement D Stable ANA titre alone

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Question 4 of 4NPLEX-LAB-056

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Oral iron treatment alone B Repeat urinalysis after one year C Reassurance without further testing D Urgent nephrology assessment and consideration of renal biopsy

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15

Clinical Case Cluster 15

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 32-year-old patient presents with dysuria, urinary frequency, fever, nausea and left flank pain. Examination shows left costovertebral-angle tenderness. Urinalysis Result component Leukocyte esterase Positive Nitrites Positive WBCs Numerous Bacteria Numerous WBC casts Present

Question 1 of 4NPLEX-LAB-057

Diagnosis Foundational

Which diagnosis is most likely?

A Acute cystitis B Interstitial cystitis C Nephrotic syndrome D Acute pyelonephritis

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Question 2 of 4NPLEX-LAB-058

Test selection and interpretation Intermediate

Which specimen is most appropriate for urine culture in a stable patient able to void?

A Midstream clean-catch urine collected before antibiotics B A random unlabelled container C Urine collected from the drainage bag of an old catheter D Twenty-four-hour urine collection

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Question 3 of 4NPLEX-LAB-059

Test selection and interpretation Intermediate

What do the WBC casts indicate?

A Contamination by vaginal secretions B Isolated bladder inflammation C Inflammation involving the renal tubules or interstitium D Glomerular bleeding

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Question 4 of 4NPLEX-LAB-060

Clinical application Intermediate–advanced

The culture reports mixed growth of several organisms, and microscopy shows abundant squamous epithelial cells. What is the best interpretation?

A Nephritic syndrome B Probable contamination requiring repeat collection C Confirmed polymicrobial pyelonephritis D Renal tuberculosis

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16

Clinical Case Cluster 16

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 24-year-old patient presents with fever, sore throat, generalized lymphadenopathy and a diffuse maculopapular rash. The patient reports a new sexual exposure approximately three weeks earlier.

Question 1 of 4NPLEX-LAB-061

Diagnosis Foundational

Which test is the preferred initial laboratory screening investigation?

A HIV Western blot alone B CD4 count alone C Fourth-generation HIV-1/2 antigen-antibody assay D Routine bacterial throat culture alone

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Question 2 of 4NPLEX-LAB-062

Test selection and interpretation Intermediate

Which test should be performed next?

A Serum ferritin B Antinuclear antibody C Repeat CBC in six months D HIV-1 nucleic-acid testing

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Question 3 of 4NPLEX-LAB-063

Test selection and interpretation Intermediate

HIV-1 RNA is strongly positive. How should the overall pattern be interpreted?

A Acute HIV infection before full antibody development B Laboratory evidence of hepatitis B C Successful vaccination against HIV D Resolved HIV infection

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Question 4 of 4NPLEX-LAB-064

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Recommend herbal monotherapy B Arrange prompt HIV specialist care and transmission-prevention counselling C Wait until the antibody differentiation test becomes positive D Reassure the patient that no follow-up is needed

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17

Clinical Case Cluster 17

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 30-year-old patient presents with fatigue, nausea, jaundice and right-upper-quadrant discomfort. Hepatitis B marker Result HBsAg Positive Total anti-HBc Positive IgM anti-HBc Positive Anti-HBs Negative

Question 1 of 4NPLEX-LAB-065

Diagnosis Foundational

Which interpretation is most appropriate?

A Immunity due to vaccination B Acute hepatitis B infection C Resolved previous infection D Chronic hepatitis B infection

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Question 2 of 4NPLEX-LAB-066

Test selection and interpretation Intermediate

Which pattern represents immunity from hepatitis B vaccination?

A Anti-HBs positive with HBsAg and anti-HBc negative B HBsAg positive with anti-HBs negative C Anti-HBc positive alone D HBsAg and IgM anti-HBc positive

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Question 3 of 4NPLEX-LAB-067

Test selection and interpretation Intermediate

Which pattern represents resolved natural hepatitis B infection?

A HBsAg positive, anti-HBs positive, anti-HBc negative B HBsAg positive, anti-HBs negative, anti-HBc positive C HBsAg negative, anti-HBs negative, anti-HBc negative D HBsAg negative, anti-HBs positive, anti-HBc positive

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Question 4 of 4NPLEX-LAB-068

Clinical application Intermediate–advanced

The patient also has a reactive hepatitis C antibody test. Which test determines whether active hepatitis C infection is present?

A Anti-HBs titre B Repeat hepatitis C antibody annually C Hepatitis C RNA assay D Serum amylase

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18

Clinical Case Cluster 18

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 19-year-old patient presents with facial swelling, dark cola-coloured urine and decreased urine output. Two weeks earlier, the patient had a severe sore throat. Test Result Creatinine Elevated Urinalysis protein 2+ Urinalysis blood 3+ RBCs Numerous and dysmorphic RBC casts Present C3 Decreased Blood pressure 158/94 mm Hg

Question 1 of 4NPLEX-LAB-069

Diagnosis Foundational

Which renal syndrome is most likely?

A Prerenal azotemia B Nephrotic syndrome C Acute nephritic syndrome D Lower urinary-tract infection

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Question 2 of 4NPLEX-LAB-070

Test selection and interpretation Intermediate

Which urinary finding most strongly localizes bleeding to the glomerulus?

A Nitrites B Red-cell casts C Calcium oxalate crystals D Squamous epithelial cells

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-071

Test selection and interpretation Intermediate

Which combination would support poststreptococcal glomerulonephritis?

A Low complement with evidence of recent streptococcal infection B Positive nitrites with isolated bacteriuria C High C3 with negative streptococcal studies D High urine glucose with normal creatinine

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-072

Clinical application Intermediate–advanced

The patient develops pulmonary edema and rapidly worsening renal function. What is the best next step?

A Reassurance and routine annual follow-up B Treat with oral iron alone C Increase dietary sodium D Urgent hospital and nephrology assessment

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References

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19

Clinical Case Cluster 19

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 68-year-old patient develops eight episodes of watery diarrhea daily after completing clindamycin. The patient has lower abdominal cramping, fever and leukocytosis. There is no visible blood.

Question 1 of 4NPLEX-LAB-073

Diagnosis Foundational

Which diagnosis is most likely?

A Irritable bowel syndrome B Chronic pancreatic insufficiency C Lactose intolerance D Clostridioides difficile infection

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-074

Test selection and interpretation Intermediate

Which specimen is appropriate for laboratory testing?

A Unformed stool from a symptomatic patient B A twenty-four-hour urine specimen C A throat swab D A formed stool from an asymptomatic patient

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-075

Test selection and interpretation Intermediate

Which practice is generally inappropriate after symptoms have resolved?

A Assessing for recurrent diarrhea B Monitoring hydration status C Performing a routine stool test of cure D Reviewing antimicrobial exposure

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-076

Clinical application Intermediate–advanced

Which finding requires urgent hospital assessment?

A Mild transient bloating B Hypotension, ileus and increasing creatinine C Two loose stools without systemic symptoms D Normal hydration and vital signs

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References

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20

Clinical Case Cluster 20

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 52-year-old patient reports that a mole on the upper back has enlarged and changed colour over six months. Examination shows a 10-mm asymmetric lesion with an irregular border, several colours and recent bleeding.

Question 1 of 4NPLEX-LAB-077

Diagnosis Foundational

Which diagnostic procedure is most appropriate?

A Observe the lesion for another year B Serum tumour-marker testing C Full-thickness excisional biopsy with a narrow diagnostic margin D Superficial scraping for fungal microscopy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-078

Test selection and interpretation Intermediate

Which histopathologic measurement is most important for staging and prognosis in invasive melanoma?

A Peripheral eosinophil count B Breslow thickness C Serum LDH alone D Lesion colour count

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-079

Test selection and interpretation Intermediate

Pathology reports melanoma in situ. Which management is generally required?

A No additional treatment after a partial biopsy B Repeat CBC only C Oral antibiotic treatment D Complete surgical excision with an appropriate margin

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-080

Clinical application Intermediate–advanced

Which action is most appropriate while awaiting definitive management?

A Arrange prompt dermatology or surgical referral B Recommend unmonitored topical therapy C Reassure the patient that bleeding excludes malignancy D Delay referral until distant symptoms occur

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References

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21

Clinical Case Cluster 21

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 72-year-old patient presents with fever, productive cough, pleuritic right-sided chest pain and increasing shortness of breath. Examination reveals a temperature of 38.8°C, respiratory rate of 26/min, oxygen saturation of 91% on room air and focal crackles over the right lower lung.

Question 1 of 4NPLEX-LAB-081

Diagnosis Foundational

Which imaging study is most appropriate initially?

A PET-CT B Ventilation-perfusion scan C MRI of the chest D Chest radiograph

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-082

Test selection and interpretation Intermediate

Which interpretation is most appropriate?

A Pulmonary hyperinflation B Lobar consolidation C Diffuse interstitial fibrosis D Pleural pneumothorax

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-083

Test selection and interpretation Intermediate

The radiograph also shows blunting of the right costophrenic angle. What does this finding most likely represent?

A Emphysema B Cardiomegaly C Pleural effusion D Pneumomediastinum

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-084

Clinical application Intermediate–advanced

The patient remains febrile and hypoxemic despite appropriate treatment. Which investigation is most appropriate to evaluate a complicated pleural effusion?

A Thoracic ultrasonography B Bone scan C Thyroid uptake scan D Abdominal radiograph

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22

Clinical Case Cluster 22

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 29-year-old patient develops sudden severe left-sided chest pain and dyspnea after blunt chest trauma. Examination shows respiratory distress, hypotension, distended neck veins and absent breath sounds over the left chest. The trachea appears displaced to the right.

Question 1 of 4NPLEX-LAB-085

Diagnosis Foundational

Which diagnosis is most likely?

A Lobar pneumonia B Cardiac tamponade C Tension pneumothorax D Massive pleural effusion

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-086

Test selection and interpretation Intermediate

What is the most appropriate next step?

A Obtain an outpatient chest radiograph B Immediate decompression without waiting for imaging C Schedule pulmonary-function testing D Order MRI of the thorax

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-087

Test selection and interpretation Intermediate

In a hemodynamically stable patient with suspected simple pneumothorax, which initial study is generally appropriate?

A Chest radiograph B Echocardiography C HIDA scan D PET-CT

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-088

Clinical application Intermediate–advanced

Which bedside ultrasound finding supports pneumothorax?

A Compressible femoral vein B Pericardial fluid surrounding the heart C Increased gallbladder-wall thickness D Absence of normal lung sliding

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23

Clinical Case Cluster 23

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 61-year-old patient with a history of abdominal surgery presents with cramping abdominal pain, vomiting, distension and inability to pass stool or flatus. Examination reveals high-pitched bowel sounds and diffuse tenderness.

Question 1 of 4NPLEX-LAB-089

Diagnosis Foundational

Which diagnosis is most likely?

A Pancreatitis B Acute hepatitis C Uncomplicated diverticulosis D Mechanical small-bowel obstruction

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-090

Test selection and interpretation Intermediate

Which imaging study best identifies the obstruction site and evaluates for ischemia or a closed-loop obstruction?

A CT of the abdomen and pelvis B Screening colonoscopy C MRI of the brain D Thyroid ultrasonography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-091

Test selection and interpretation Intermediate

Which plain-radiograph finding supports small-bowel obstruction?

A A solitary calcified gallstone B Dilated central small-bowel loops with multiple air-fluid levels C Loss of all bowel gas D Bilateral hilar enlargement

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-092

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Begin a high-fibre diet B Repeat imaging in six months C Emergency surgical assessment D Routine outpatient follow-up

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References

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24

Clinical Case Cluster 24

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 46-year-old patient presents with persistent right-upper-quadrant pain, fever and vomiting. The pain began after a fatty meal and radiates to the right scapula. Examination reveals focal tenderness and inspiratory arrest during right-upper-quadrant palpation.

Question 1 of 4NPLEX-LAB-093

Diagnosis Foundational

Which imaging study is most appropriate initially?

A Right-upper-quadrant ultrasonography B Nuclear bone scan C Chest CT D MRI of the spine

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-094

Test selection and interpretation Intermediate

Which ultrasound combination most strongly supports acute cholecystitis?

A Bilateral renal cysts B Gallstones, wall thickening and a sonographic Murphy sign C Isolated fatty liver D Normal gallbladder wall and no stones

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-095

Test selection and interpretation Intermediate

Ultrasonography is equivocal, but clinical suspicion remains high. Which investigation is most appropriate next?

A Mammography B Electroencephalography C DXA scan D Hepatobiliary iminodiacetic acid scan

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-096

Clinical application Intermediate–advanced

The patient develops jaundice, fever, hypotension and confusion. What is the most appropriate action?

A Begin dietary fat restriction alone B Arrange outpatient physiotherapy C Emergency hospital referral for possible ascending cholangitis D Routine repeat ultrasound in one year

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25

Clinical Case Cluster 25

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 30-year-old patient presents with six weeks of amenorrhea, unilateral pelvic pain and light vaginal bleeding. A urine pregnancy test is positive. Blood pressure is 116/72 mm Hg, and the patient is hemodynamically stable.

Question 1 of 4NPLEX-LAB-097

Diagnosis Foundational

Which investigation combination is most appropriate initially?

A Abdominal radiograph and serum progesterone alone B Quantitative serum hCG and transvaginal ultrasonography C Pelvic CT with contrast D Hysteroscopy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-098

Test selection and interpretation Intermediate

Which term best describes the current finding?

A Pregnancy of unknown location B Complete spontaneous abortion C Confirmed ruptured ectopic pregnancy D Confirmed viable intrauterine pregnancy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-099

Test selection and interpretation Intermediate

What is the most appropriate next step in this stable patient?

A Obtain a pelvic radiograph B Reassure the patient that ectopic pregnancy is excluded C Serial quantitative hCG measurements with repeat ultrasonography D Delay all assessment until the second trimester

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-100

Clinical application Intermediate–advanced

What is the most appropriate action?

A Repeat hCG after one week B Arrange routine prenatal care C Perform a screening mammogram D Emergency gynecologic and surgical management

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References

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26

Clinical Case Cluster 26

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 58-year-old patient presents with unilateral calf swelling and pain five days after hip-replacement surgery. The affected calf is 4 cm larger than the opposite side.

Question 1 of 4NPLEX-LAB-101

Diagnosis Foundational

Which imaging study is most appropriate initially?

A Compression ultrasonography B Abdominal CT C MRI of the brain D Plain radiograph of the leg

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-102

Test selection and interpretation Intermediate

Which ultrasound finding supports acute DVT?

A Complete venous collapse with probe pressure B Failure of the vein to compress C Normal arterial pulsation D Normal venous flow augmentation

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-103

Test selection and interpretation Intermediate

Initial proximal ultrasound is negative, but clinical suspicion remains high. What is the most appropriate next step?

A Obtain a routine chest radiograph only B Exclude DVT permanently C Arrange serial or repeat venous ultrasonography D Perform thyroid ultrasonography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-104

Clinical application Intermediate–advanced

Which imaging study is generally preferred to evaluate pulmonary embolism in a stable patient without a major contraindication to contrast?

A Skull radiography B Pelvic MRI C HIDA scanning D CT pulmonary angiography

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27

Clinical Case Cluster 27

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 69-year-old patient develops sudden right-sided weakness, facial droop and expressive aphasia 45 minutes before arrival. Blood glucose is normal.

Question 1 of 4NPLEX-LAB-105

Diagnosis Foundational

Which imaging study should be obtained immediately?

A PET-CT of the brain B Noncontrast CT of the head C MRI of the lumbar spine D Carotid radiograph

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-106

Test selection and interpretation Intermediate

Which study can identify a proximal large-vessel occlusion and help determine eligibility for mechanical thrombectomy?

A Bone scintigraphy B Abdominal ultrasound C CT angiography of the head and neck D Thyroid uptake scan

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-107

Test selection and interpretation Intermediate

Which MRI sequence is especially sensitive for early cerebral ischemia?

A Diffusion-weighted imaging B T1-weighted imaging alone C Proton-density knee imaging D MRCP

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-108

Clinical application Intermediate–advanced

What is the most important management principle?

A Repeat neurologic examination the following week B Wait for MRI before initiating any stroke pathway C Begin long-term rehabilitation before assessing reperfusion eligibility D Do not delay time-sensitive treatment for unnecessary imaging

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28

Clinical Case Cluster 28

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 41-year-old patient presents with sudden severe left-flank pain radiating to the groin, nausea and microscopic hematuria. The patient is not pregnant and has no known kidney disease.

Question 1 of 4NPLEX-LAB-109

Diagnosis Foundational

Which imaging study is most sensitive for detecting a ureteral stone in this patient?

A Noncontrast CT of the abdomen and pelvis B Intravenous pyelography as the only option C MRI of the pelvis D Contrast-enhanced chest CT

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-110

Test selection and interpretation Intermediate

Which imaging method is generally preferred initially when renal colic is suspected during pregnancy?

A Nuclear bone scan B Renal ultrasonography C CT pulmonary angiography D Abdominal radiograph series

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-111

Test selection and interpretation Intermediate

Which ultrasound finding suggests urinary obstruction?

A Free pleural air B Noncompressible femoral vein C Hydronephrosis D Thickened gallbladder wall

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-112

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Routine repeat CT in one year B Begin calcium supplementation C Outpatient hydration alone D Emergency antimicrobial therapy and urinary decompression

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Answer and Diagnostic Rationale

References

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29

Clinical Case Cluster 29

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 48-year-old patient with severe low-back pain develops bilateral leg weakness, saddle anesthesia, urinary retention and reduced anal sphincter tone.

Question 1 of 4NPLEX-LAB-113

Diagnosis Foundational

Which imaging study is most appropriate?

A DXA scan B Bone-age radiograph C Lumbar radiograph only D Emergency MRI of the lumbosacral spine

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-114

Test selection and interpretation Intermediate

Why is a plain lumbar radiograph insufficient?

A It does not adequately evaluate nerve-root or soft-tissue compression B It cannot demonstrate vertebral alignment C It cannot identify any fractures D It always exposes the patient to excessive radiation

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-115

Test selection and interpretation Intermediate

Which alternative may be considered when MRI is absolutely contraindicated or unavailable?

A Thyroid ultrasound B CT myelography C Screening mammography D HIDA scan

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-116

Clinical application Intermediate–advanced

What is the most appropriate next step after imaging confirms cauda equina compression?

A Repeat imaging in six months B Routine physiotherapy referral only C Emergency spinal surgical consultation D Bed rest without specialist assessment

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30

Clinical Case Cluster 30

4 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 66-year-old patient with a 45-pack-year smoking history presents with persistent cough, hemoptysis and unintentional weight loss. Chest radiography shows a right-upper-lobe opacity. CT demonstrates a 3.8-cm spiculated mass with enlarged mediastinal lymph nodes.

Question 1 of 4NPLEX-LAB-117

Diagnosis Foundational

Which interpretation is most appropriate?

A No further evaluation is required B Findings are diagnostic of benign pneumonia C The lesion represents a simple pneumothorax D The lesion is highly suspicious for pulmonary malignancy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 4NPLEX-LAB-118

Test selection and interpretation Intermediate

What is the primary role of PET-CT in this situation?

A Assess metabolic activity and identify possible metastatic disease B Provide definitive histologic diagnosis C Replace all tissue sampling D Measure pulmonary-function values

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 4NPLEX-LAB-119

Test selection and interpretation Intermediate

Which investigation is required to establish the definitive diagnosis?

A Serum tumour markers alone B Repeat chest radiography alone C Tissue biopsy with histopathologic examination D Pulmonary-function testing alone

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 4NPLEX-LAB-120

Clinical application Intermediate–advanced

The patient develops new headaches and focal weakness. Which imaging study is most appropriate to evaluate possible brain metastases?

A Plain skull radiograph B Contrast-enhanced MRI of the brain C Abdominal ultrasonography D HIDA scan

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31

Clinical Case Cluster 31

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 58-year-old patient presents with 45 minutes of crushing substernal chest pressure, diaphoresis, nausea and weakness. Blood pressure is 86/58 mm Hg, pulse is 54/min and oxygen saturation is 95% on room air. The jugular venous pressure is elevated, but the lungs are clear. The ECG demonstrates: ● ST-segment elevation in leads II, III and aVF ● Reciprocal ST depression in leads I and aVL ● ST elevation in lead III greater than lead II

Question 1 of 6NPLEX-LAB-121

Diagnosis Foundational

Which ECG diagnosis is most likely?

A Acute anterior STEMI B Left bundle-branch block C Acute inferior STEMI D Acute pericarditis

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-122

Test selection and interpretation Intermediate

Which coronary artery is most likely involved, given the hypotension, elevated jugular venous pressure and clear lungs?

A First diagonal artery B Right coronary artery C Left main coronary artery D Left anterior descending artery

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-123

Test selection and interpretation Intermediate

Which additional ECG investigation is most appropriate?

A Twenty-four-hour Holter monitoring B Signal-averaged ECG C Right-sided precordial leads, particularly V4R D Exercise stress testing

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-124

Clinical application Intermediate–advanced

The first high-sensitivity troponin result is within the laboratory reference interval. What is the best interpretation?

A The patient should undergo outpatient stress testing B The ECG changes are probably benign C Myocardial infarction is excluded D An early normal troponin does not exclude acute STEMI

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-125

Clinical application Intermediate–advanced

Which medication requires particular caution in this patient?

A A P2Y12 inhibitor B Nitroglycerin C Unfractionated heparin D Aspirin

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-126

Safety and escalation Advanced

What is the most appropriate next step?

A Activate emergency reperfusion management B Arrange outpatient echocardiography C Schedule exercise testing within one week D Repeat the ECG in three months

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32

Clinical Case Cluster 32

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 67-year-old patient reports sudden episodes of rapid, irregular palpitations lasting between 30 minutes and 4 hours. Episodes occur approximately twice weekly. There is associated fatigue and mild dyspnea but no syncope. During one episode, a 12-lead ECG shows: ● Ventricular rate: 138/min ● Irregularly irregular R–R intervals ● No consistent P waves ● Narrow QRS complexes

Question 1 of 6NPLEX-LAB-127

Diagnosis Foundational

Which rhythm is present?

A Atrial flutter with fixed conduction B Monomorphic ventricular tachycardia C Atrial fibrillation D Sinus tachycardia

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-128

Test selection and interpretation Intermediate

Which test is most appropriate for evaluating cardiac structure and function?

A Pulmonary-function testing B Noncontrast head CT C Carotid ultrasonography D Transthoracic echocardiography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-129

Test selection and interpretation Intermediate

Which monitoring method is most likely to capture episodes occurring twice weekly?

A Extended ambulatory patch or event monitor B Routine annual ECG C Exercise ECG only D Implantable monitor as the mandatory first test

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-130

Clinical application Intermediate–advanced

Which laboratory combination is appropriate when evaluating a newly identified atrial arrhythmia?

A Ferritin and hemoglobin electrophoresis B Rheumatoid factor and ANA C Amylase and lipase D Electrolytes and thyroid-function tests

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-131

Clinical application Intermediate–advanced

The patient has hypertension, diabetes and a previous transient ischemic attack. What additional assessment is essential?

A Child-Pugh classification B Thromboembolic and bleeding-risk assessment C Fracture-risk calculation D Pulmonary-embolism severity score

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-132

Safety and escalation Advanced

During a later episode, the patient develops hypotension, pulmonary edema and altered mental status. What is the immediate intervention?

A Synchronized electrical cardioversion B Repeat ambulatory monitoring C Oral rate-control treatment followed by discharge D Routine outpatient echocardiography

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33

Clinical Case Cluster 33

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 78-year-old patient presents after syncope. The patient reports several days of fatigue and exertional dizziness. Pulse is 32/min and blood pressure is 84/52 mm Hg. The ECG demonstrates: ● Regular P waves at 82/min ● Regular QRS complexes at 31/min ● No consistent relationship between P waves and QRS complexes ● Wide ventricular escape complexes

Question 1 of 6NPLEX-LAB-133

Diagnosis Foundational

Which conduction disorder is present?

A First-degree AV block B Mobitz type I second-degree AV block C Sinus bradycardia D Third-degree AV block

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-134

Test selection and interpretation Intermediate

Which ECG feature establishes the diagnosis?

A An irregularly irregular ventricular rhythm B A constant prolonged PR interval C Atrioventricular dissociation D Gradual PR prolongation before a dropped beat

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-135

Test selection and interpretation Intermediate

Which evaluation is appropriate for potentially reversible causes?

A Pulmonary-function testing B Medication review, electrolytes and ischemia assessment C Stool culture and calprotectin D Serum ferritin only

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-136

Clinical application Intermediate–advanced

What is the most appropriate immediate intervention in this unstable patient?

A Initiate emergency pacing while providing resuscitative support B Repeat the ECG after one week C Arrange routine Holter monitoring D Begin an exercise program

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-137

Clinical application Intermediate–advanced

No reversible cause is identified. Which long-term treatment is generally indicated?

A Implantable loop recorder alone B Catheter ablation of the atrium C Long-term anticoagulation alone D Permanent pacemaker placement

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-138

Safety and escalation Advanced

Which monitoring is most appropriate while awaiting definitive treatment?

A Annual resting ECG B Continuous cardiac telemetry C Peak expiratory-flow monitoring D Home blood-pressure diary only

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34

Clinical Case Cluster 34

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 54-year-old patient taking sotalol is prescribed a macrolide antibiotic. After three days of vomiting, the patient develops recurrent dizziness and syncope. Test Result Potassium 2.9 mmol/L Magnesium 1.3 mg/dL Creatinine Elevated QTc 560 milliseconds Telemetry records bursts of polymorphic wide-complex tachycardia in which the QRS axis appears to rotate around the baseline.

Question 1 of 6NPLEX-LAB-139

Diagnosis Foundational

Which abnormality predisposed this patient to the ventricular arrhythmia?

A Acquired QT-interval prolongation B Early repolarization C Short PR interval D First-degree AV block

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-140

Test selection and interpretation Intermediate

Which rhythm is demonstrated on telemetry?

A Atrial fibrillation with aberrancy B Monomorphic ventricular tachycardia C Torsades de pointes D Supraventricular tachycardia

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-141

Test selection and interpretation Intermediate

Which action is most appropriate after immediate stabilization?

A Continue all medications and repeat the ECG in one year B Restrict dietary magnesium C Increase the sotalol dose D Stop contributing medications and correct potassium and magnesium

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-142

Clinical application Intermediate–advanced

The patient becomes pulseless during sustained polymorphic ventricular tachycardia. What is the immediate treatment?

A Immediate unsynchronized defibrillation B Synchronized cardioversion C Oral magnesium D Carotid massage

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-143

Clinical application Intermediate–advanced

Which medication is specifically used for recurrent torsades associated with prolonged QT?

A Intravenous calcium gluconate B Adenosine C Intravenous magnesium D Oral digoxin

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-144

Safety and escalation Advanced

Which studies should be followed after treatment?

A Lipase and fecal elastase B Serial ECGs, QTc and electrolyte levels C ESR and CRP D Urine albumin-to-creatinine ratio only

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35

Clinical Case Cluster 35

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 36-year-old patient presents with sharp central chest pain that worsens with inspiration and lying flat and improves while sitting forward. A pericardial friction rub is present. The ECG shows: ● Diffuse concave ST-segment elevation ● PR-segment depression ● No localized reciprocal changes except in aVR

Question 1 of 6NPLEX-LAB-145

Diagnosis Foundational

Which diagnosis best explains the initial findings?

A Acute posterior myocardial infarction B Pulmonary embolism C Early repolarization without symptoms D Acute pericarditis

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-146

Test selection and interpretation Intermediate

Which ECG feature most strongly distinguishes this pattern from a typical STEMI?

A Sinus tachycardia B Diffuse rather than coronary-territory ST changes C Presence of any ST elevation D A shortened QT interval

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-147

Test selection and interpretation Intermediate

Which imaging investigation should be performed to evaluate for an effusion?

A Transthoracic echocardiography B Carotid Doppler ultrasonography C CT pulmonary angiography D Coronary calcium scoring

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-148

Clinical application Intermediate–advanced

Which echocardiographic finding most strongly supports tamponade physiology?

A A calcified aortic valve B Isolated left-ventricular hypertrophy C Mild mitral regurgitation D Right-atrial or right-ventricular chamber collapse

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-149

Clinical application Intermediate–advanced

Which ECG finding may occur with a large pericardial effusion?

A Persistent delta waves B Electrical alternans C Shortened PR interval D Isolated pathologic Q waves

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-150

Safety and escalation Advanced

The patient remains hypotensive with echocardiographic evidence of tamponade. What is the most appropriate next step?

A Exercise stress testing B Repeat ECG after six weeks C Emergency pericardial drainage D Routine outpatient follow-up

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36

Clinical Case Cluster 36

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 64-year-old patient presents with progressive exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea and bilateral ankle edema. Examination reveals elevated jugular venous pressure, pulmonary crackles and an S3 heart sound. Chest radiography shows cardiomegaly and pulmonary vascular congestion. BNP is elevated.

Question 1 of 6NPLEX-LAB-151

Diagnosis Foundational

Which investigation is most appropriate for evaluating cardiac structure and systolic function?

A Transthoracic echocardiography B Ventilation-perfusion scanning C Holter monitoring D Coronary calcium scoring

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-152

Test selection and interpretation Intermediate

How should the ventricular dysfunction be classified?

A Heart failure with preserved ejection fraction B Normal ventricular function C Heart failure with reduced ejection fraction D Isolated right-heart failure

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-153

Test selection and interpretation Intermediate

What does the ejection fraction represent?

A The percentage of total blood volume passing through the heart hourly B The proportion of end-diastolic ventricular volume ejected per beat C The percentage of blood remaining in the ventricle after contraction D The pressure inside the left atrium

Reveal Answer Flag

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References

Question 4 of 6NPLEX-LAB-154

Clinical application Intermediate–advanced

Which echocardiographic finding would more strongly suggest an ischemic cause?

A A small physiologic pericardial effusion B Normal right-ventricular size C Regional wall-motion abnormalities D Mild left-atrial enlargement

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Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-155

Clinical application Intermediate–advanced

A different patient has heart-failure symptoms but an ejection fraction of 60%. Which statement is correct?

A Heart failure is completely excluded B Echocardiography has no further role C The symptoms must be pulmonary in origin D Preserved ejection fraction does not exclude heart failure

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References

Question 6 of 6NPLEX-LAB-156

Safety and escalation Advanced

When is repeat echocardiography most appropriate?

A After a major clinical change or treatment period when the result may alter management B Never after the initial diagnosis C Every week regardless of symptoms D Only after cardiac arrest

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37

Clinical Case Cluster 37

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 24-year-old patient reports episodic wheezing, chest tightness and cough triggered by exercise, cold air and exposure to cats. Symptoms vary substantially from week to week. Spirometry demonstrates: Measurement Before bronchodilator After bronchodilator FEV₁ Reduced Substantially improved FVC Near normal Near normal FEV₁/FVC Below lower limit of normal Improved

Question 1 of 6NPLEX-LAB-157

Diagnosis Foundational

Which ventilatory pattern is present before bronchodilator administration?

A Normal spirometry B Isolated diffusion impairment C Obstructive ventilatory defect D Restrictive defect

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-158

Test selection and interpretation Intermediate

Which diagnosis is most strongly supported by the clinical history and bronchodilator response?

A Asthma B Pleural effusion C Idiopathic pulmonary fibrosis D Neuromuscular respiratory weakness

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-159

Test selection and interpretation Intermediate

Which spirometric measurement is most useful for identifying airflow obstruction?

A Diffusing capacity alone B Residual volume alone C Total lung capacity alone D FEV₁/FVC ratio

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-160

Clinical application Intermediate–advanced

Spirometry is normal during an asymptomatic period, but clinical suspicion remains high. Which study may help demonstrate variable airway hyperresponsiveness?

A Bronchoprovocation testing B Chest PET scan C Pleural biopsy D Pulmonary angiography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-161

Clinical application Intermediate–advanced

Which home measurement may help document variability over time?

A Twenty-four-hour urine volume B Resting ECG interval C Daily oxygen-tank weight D Serial peak expiratory-flow measurements

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Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-162

Safety and escalation Advanced

The patient presents with severe respiratory distress, inability to speak full sentences and oxygen saturation of 85%. What is the priority?

A Arrange routine follow-up in one month B Begin emergency stabilization and treatment C Perform elective bronchoprovocation testing D Delay treatment until complete spirometry is obtained

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38

Clinical Case Cluster 38

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 62-year-old patient presents with progressive exertional dyspnea and dry cough. Examination reveals digital clubbing and fine inspiratory crackles at both lung bases. Pulmonary-function testing shows: Measurement Result FEV₁ Reduced FVC Reduced FEV₁/FVC Normal to elevated Total lung capacity Reduced DLCO Reduced

Question 1 of 6NPLEX-LAB-163

Diagnosis Foundational

Which ventilatory pattern is present?

A Restrictive ventilatory defect B Obstructive ventilatory defect C Normal pulmonary function D Isolated upper-airway obstruction

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-164

Test selection and interpretation Intermediate

Which measurement confirms true pulmonary restriction?

A Respiratory rate B Total lung capacity C Peak expiratory flow D FEV₁ alone

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-165

Test selection and interpretation Intermediate

What does the reduced DLCO suggest?

A Isolated upper-airway disease B Normal alveolar-capillary function C Impaired transfer of gas across the alveolar-capillary interface D Increased pulmonary capillary gas transfer

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-166

Clinical application Intermediate–advanced

Which imaging study is most appropriate for characterizing suspected interstitial lung disease?

A Routine abdominal CT B Plain radiography of the lumbar spine C Ventilation-perfusion scanning as the only study D High-resolution CT of the chest

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Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-167

Clinical application Intermediate–advanced

Which pattern is more consistent with restriction caused by obesity rather than intrinsic interstitial lung disease?

A Isolated prolonged expiratory time B Reduced lung volumes with a relatively preserved DLCO C Markedly increased TLC D Severe obstruction with bronchodilator reversibility

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Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-168

Safety and escalation Advanced

The patient has rapidly progressive dyspnea and severe exertional desaturation. What is the most appropriate next step?

A Begin unsupervised exercise without further evaluation B Repeat spirometry after one year C Urgent pulmonary assessment and oxygenation evaluation D Reassure the patient that restriction is benign

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39

Clinical Case Cluster 39

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 34-year-old patient experiences sudden loss of consciousness followed by generalized tonic-clonic movements lasting approximately two minutes. There is post-event confusion for 25 minutes. Blood glucose and electrolytes are normal. Noncontrast head CT shows no acute abnormality.

Question 1 of 6NPLEX-LAB-169

Diagnosis Foundational

Which neurodiagnostic investigation is appropriate after stabilization?

A Electroencephalography B Lumbar-spine MRI C Carotid ultrasonography only D Nerve-conduction studies

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Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-170

Test selection and interpretation Intermediate

Which EEG finding is associated with a higher risk of another seizure?

A Eye-blink artifact B Epileptiform discharges C Normal posterior dominant rhythm D Muscle artifact during movement

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-171

Test selection and interpretation Intermediate

The routine EEG is normal. What is the best interpretation?

A The patient cannot have another seizure B Brain imaging is unnecessary C The event was definitely psychogenic D A normal EEG does not exclude epilepsy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-172

Clinical application Intermediate–advanced

Which imaging study is preferred for identifying a subtle structural seizure focus after an unprovoked seizure?

A Brain MRI using an epilepsy-oriented protocol B Carotid Doppler testing C Bone scintigraphy D Plain skull radiography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-173

Clinical application Intermediate–advanced

The patient develops recurrent episodes of uncertain origin despite normal routine studies. Which test best correlates clinical behaviour with cerebral electrical activity?

A Echocardiography B Prolonged video-EEG monitoring C Electromyography of the legs D Twenty-four-hour blood-pressure monitoring

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-174

Safety and escalation Advanced

A later convulsive seizure continues for more than five minutes without recovery. What is the priority?

A Wait for spontaneous resolution B Schedule an outpatient EEG C Initiate emergency treatment for status epilepticus D Arrange routine MRI after one month

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40

Clinical Case Cluster 40

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 49-year-old patient reports nocturnal numbness and tingling involving the thumb, index finger and middle finger of the dominant hand. Shaking the hand temporarily relieves the symptoms. Examination shows reduced thumb-abduction strength and mild thenar wasting.

Question 1 of 6NPLEX-LAB-175

Diagnosis Foundational

Which diagnostic study is most appropriate to localize and assess the severity of the suspected nerve lesion?

A EEG B Nerve-conduction studies with needle electromyography when indicated C Brain PET scan D Lumbar puncture

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-176

Test selection and interpretation Intermediate

Which nerve-conduction pattern most strongly supports median neuropathy at the wrist?

A Isolated slowing across the elbow in the ulnar nerve B Normal median conduction with abnormal tibial conduction only C Diffusely absent responses in every tested nerve D Prolonged median distal latency with relatively normal ulnar conduction

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-177

Test selection and interpretation Intermediate

Which needle-EMG finding suggests axonal loss and more advanced median neuropathy?

A Denervation abnormalities in median-innervated thenar muscles B Isolated paraspinal abnormalities without hand findings C Normal motor-unit recruitment D Normal insertional activity in every muscle

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-178

Clinical application Intermediate–advanced

Which finding would favour cervical radiculopathy rather than an isolated median neuropathy?

A Slowed median conduction across the wrist B Thenar weakness with abnormal median sensory latency C Myotomal EMG abnormalities with relatively preserved sensory nerve responses D Numbness limited to the first three digits at night

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Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-179

Clinical application Intermediate–advanced

Which investigation provides the best anatomic assessment when cervical cord or nerve-root compression is suspected?

A Carotid ultrasound B Hand radiograph C EEG D MRI of the cervical spine

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-180

Safety and escalation Advanced

Which finding warrants prompt specialist referral rather than prolonged conservative observation?

A Symptoms only after sleeping on the hand once B Mild intermittent tingling without weakness C Progressive weakness and thenar muscle atrophy D A normal neurologic examination

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41

Clinical Case Cluster 41

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 35-year-old asymptomatic patient undergoes routine cervical cancer screening. The patient has no history of cervical intraepithelial neoplasia, immunosuppression or cervical cancer. The results show: ● High-risk HPV: Positive ● HPV genotype 16: Positive ● Cervical cytology: Negative for intraepithelial lesion or malignancy

Question 1 of 6NPLEX-LAB-181

Diagnosis Foundational

How should the result be interpreted?

A The patient has metastatic HPV-related cancer B A high-risk screening result requires further evaluation C Cervical cancer has been definitively diagnosed D The result is normal because cytology is negative

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-182

Test selection and interpretation Intermediate

What is the most appropriate next investigation?

A Colposcopy with directed biopsy when indicated B Repeat cytology in ten years C Pelvic CT D Endometrial biopsy

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-183

Test selection and interpretation Intermediate

Which investigation establishes the histologic diagnosis of cervical intraepithelial neoplasia?

A Repeat HPV testing alone B Serum tumour-marker measurement C Cervical tissue biopsy D Pelvic ultrasonography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-184

Clinical application Intermediate–advanced

The patient previously received a complete HPV-vaccine series. How should this affect future screening?

A Routine screening should continue according to risk and age B Only pelvic ultrasound is required C All cervical screening can be permanently discontinued D Screening is needed only when symptoms develop

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Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-185

Clinical application Intermediate–advanced

One year later, the patient reports persistent postcoital bleeding. What is the best approach?

A Wait until the next routine screening interval B Reassure the patient because the previous cytology was negative C Repeat only the HPV vaccine D Perform a diagnostic gynecologic evaluation

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-186

Safety and escalation Advanced

Which patient should not automatically be managed using an average-risk cervical screening schedule?

A A patient using a copper intrauterine device B A patient with significant immunosuppression C A patient with seasonal allergies D A patient with treated iron deficiency

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42

Clinical Case Cluster 42

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 47-year-old patient discovers a new firm mass in the upper outer quadrant of the left breast. Examination confirms a 2.5-cm irregular, poorly mobile mass. There is no fever or recent trauma.

Question 1 of 6NPLEX-LAB-187

Diagnosis Foundational

How should the imaging assessment be classified?

A Diagnostic breast evaluation B Population surveillance C Routine screening D Genetic screening

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-188

Test selection and interpretation Intermediate

Which imaging combination is most appropriate initially?

A PET-CT without breast imaging B Chest radiography and bone scan C Screening mammography in two years D Diagnostic mammography and targeted breast ultrasonography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-189

Test selection and interpretation Intermediate

Imaging reports a BI-RADS 5 irregular spiculated mass. What is the next step?

A Begin antibiotics without tissue testing B Routine screening after two years C Image-guided tissue biopsy D Repeat clinical examination in one year

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-190

Clinical application Intermediate–advanced

Why is core-needle biopsy generally preferred over fine-needle aspiration for a suspicious solid breast mass?

A It eliminates all sampling error B It preserves tissue architecture for histology and biomarker testing C It does not require imaging guidance D It provides complete surgical treatment

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-191

Clinical application Intermediate–advanced

The mammogram is reported as negative, but the hard palpable mass remains clinically concerning. What is the best next step?

A Begin screening stool testing B Permanently exclude malignancy C Wait five years before repeating the examination D Continue targeted evaluation and obtain tissue diagnosis if indicated

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-192

Safety and escalation Advanced

For an average-risk asymptomatic patient, which current USPSTF screening approach is recommended?

A Annual breast MRI from age 20 B Mammography only after age 75 C Biennial mammography from age 40 through 74 D Routine PET-CT every five years

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43

Clinical Case Cluster 43

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 56-year-old asymptomatic patient at average colorectal-cancer risk completes an annual fecal immunochemical test. The result is positive. The patient has no visible rectal bleeding.

Question 1 of 6NPLEX-LAB-193

Diagnosis Foundational

What is the most appropriate next step?

A Begin iron supplementation B Arrange colonoscopy C Repeat the FIT immediately D Order abdominal ultrasonography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-194

Test selection and interpretation Intermediate

Why should the FIT not simply be repeated to determine whether the first result was false positive?

A Colonoscopy is unnecessary after positive FIT B FIT cannot detect blood C FIT always diagnoses colorectal cancer D A positive stool test requires direct colonic evaluation

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-195

Test selection and interpretation Intermediate

Which statement about FIT is correct?

A It visualizes the entire colon B It requires a barium preparation C It uses antibodies to detect human blood in stool D It directly removes polyps

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-196

Clinical application Intermediate–advanced

A different patient presents with iron-deficiency anemia, weight loss and altered bowel habits. Which statement is most accurate?

A Testing should wait until age 65 B The patient requires diagnostic evaluation C Only annual FIT is necessary D This remains routine screening

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-197

Clinical application Intermediate–advanced

Colonoscopy identifies and removes a polyp. Which finding most directly guides the surveillance interval?

A The number, size and histopathology of the polyps B The initial FIT value alone C The patient’s shoe size D The colour of the stool

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-198

Safety and escalation Advanced

Several hours after colonoscopic polypectomy, the patient develops severe abdominal pain, tachycardia, fever and guarding. What is the best next step?

A Begin fibre supplementation B Repeat FIT at home C Emergency assessment for perforation or another procedural complication D Routine review in one year

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44

Clinical Case Cluster 44

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 68-year-old postmenopausal patient undergoes bone-mineral-density testing. There is no previous fragility fracture. DXA results show: Site T-score Lumbar spine −2.7 Total hip −2.3 Femoral neck −2.6

Question 1 of 6NPLEX-LAB-199

Diagnosis Foundational

How should the DXA findings be classified?

A Osteoarthritis B Normal bone density C Osteomalacia confirmed by DXA D Osteoporosis

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-200

Test selection and interpretation Intermediate

What does a T-score compare?

A Current BMD with the same patient’s childhood BMD B BMD with people of the same exact height C BMD with that of a healthy young-adult reference population D Calcium intake with national recommendations

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-201

Test selection and interpretation Intermediate

Which measurement is generally preferred when assessing a premenopausal adult or younger patient?

A Z-score B Peak expiratory flow C INR D Corrected calcium

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-202

Clinical application Intermediate–advanced

Which test is the preferred central measurement for diagnosing osteoporosis?

A Heel ultrasound alone B DXA of the hip and lumbar spine C Whole-body PET imaging D Routine knee radiography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-203

Clinical application Intermediate–advanced

Which laboratory evaluation is appropriate when investigating possible secondary contributors?

A Sputum culture and Gram stain B D-dimer alone C Cardiac troponin alone D Calcium, renal function, vitamin D and selected endocrine studies

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-204

Safety and escalation Advanced

The patient falls and develops severe hip pain with inability to bear weight. Which investigation is most appropriate initially?

A Hip and pelvis radiographs B Routine PET-CT C Bone-density ultrasound D Repeat DXA

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45

Clinical Case Cluster 45

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 69-year-old asymptomatic man has a 35-pack-year smoking history. There is no previous abdominal aortic imaging.

Question 1 of 6NPLEX-LAB-205

Diagnosis Foundational

Which screening investigation is most appropriate?

A Abdominal radiograph B One-time abdominal ultrasonography C Exercise ECG D MRI of the brain

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-206

Test selection and interpretation Intermediate

Which statement is most accurate?

A The patient has a normal age-related finding B Immediate rupture is certain C An aneurysm has been detected and requires vascular follow-up D The result excludes an aneurysm

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-207

Test selection and interpretation Intermediate

What is the principal limitation of screening ultrasonography compared with CT angiography?

A It provides less detailed branch-vessel and operative anatomy B It cannot measure aortic diameter C It always requires iodinated contrast D It produces greater radiation exposure

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-208

Clinical application Intermediate–advanced

Which study is most appropriate when detailed preoperative anatomy is required?

A DXA scanning B HIDA scanning C CT angiography D Plain chest radiography

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-209

Clinical application Intermediate–advanced

The patient suddenly develops severe abdominal and back pain, syncope and hypotension. What is the best next step?

A Activate emergency vascular and resuscitative management B Schedule routine surveillance ultrasonography C Arrange outpatient colonoscopy D Repeat screening in one year

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-210

Safety and escalation Advanced

For which population does the USPSTF recommend against routine AAA screening?

A Men aged 65–75 who have ever smoked B Men with a strong family history C Symptomatic patients with abdominal pain D Women who have never smoked and have no family history of AAA

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46

Clinical Case Cluster 46

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 39-year-old patient at 11 weeks’ gestation completes cell-free DNA screening. The report indicates a high probability of trisomy 21. Ultrasonography confirms a viable intrauterine pregnancy.

Question 1 of 6NPLEX-LAB-211

Diagnosis Foundational

How should the cell-free DNA result be interpreted?

A The fetus has no other possible abnormalities B It is a screening result, not a definitive fetal diagnosis C No further discussion is required D Trisomy 21 has been confirmed

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-212

Test selection and interpretation Intermediate

What is the most appropriate next step?

A Terminate the pregnancy without confirmation B Repeat cell-free DNA every week C Obtain an abdominal radiograph D Genetic counselling and an offer of diagnostic testing

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Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-213

Test selection and interpretation Intermediate

Which specimen is obtained during chorionic villus sampling?

A Placental chorionic tissue B Maternal liver tissue C Fetal bone marrow D Amniotic fluid only

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Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-214

Clinical application Intermediate–advanced

Which procedure obtains amniotic fluid containing fetal cells?

A Endometrial biopsy B Hysteroscopy C Colposcopy D Amniocentesis

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-215

Clinical application Intermediate–advanced

Cell-free DNA screening is negative. Which statement is correct?

A An anatomy ultrasound is no longer needed B Diagnostic certainty is 100% C Routine structural fetal assessment remains necessary D All fetal disorders are excluded

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-216

Safety and escalation Advanced

Which principle is most appropriate before making an irreversible pregnancy-management decision after a positive screening result?

A Treat the screening result as definitive pathology B Obtain diagnostic confirmation whenever feasible C Base the decision on maternal age alone D Ignore the patient’s preferences

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47

Clinical Case Cluster 47

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A healthy-appearing newborn undergoes routine dried-blood-spot screening. The screen reports markedly elevated TSH. The infant has mild prolonged jaundice and feeds slowly.

Question 1 of 6NPLEX-LAB-217

Diagnosis Foundational

How should the newborn screening result be interpreted?

A The result confirms pituitary disease B The infant definitely has permanent hypothyroidism C No follow-up is needed because the infant appears well D The abnormal screen requires urgent confirmatory testing

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-218

Test selection and interpretation Intermediate

Which confirmatory laboratory tests are most appropriate?

A Serum cortisol alone B Serum TSH and free T4 C Urine iodine alone D Serum calcium and phosphate

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-219

Test selection and interpretation Intermediate

Which diagnosis is most likely?

A Normal physiologic adaptation B Neonatal Graves disease C Primary congenital hypothyroidism D Central hyperthyroidism

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-220

Clinical application Intermediate–advanced

What is the most appropriate next step?

A Begin iodine supplementation without evaluating the cause B Begin prompt levothyroxine treatment with specialist follow-up C Repeat testing after one year D Wait until symptoms become more obvious

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-221

Clinical application Intermediate–advanced

Which tests are used to monitor replacement therapy?

A Serial TSH and free T4 B PT and INR C Ferritin and reticulocyte count D AST and ALT

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 6 of 6NPLEX-LAB-222

Safety and escalation Advanced

Which infant may require repeat or specially timed thyroid screening despite an initially reassuring result?

A An infant with a normal hearing test B A healthy term infant with reliable screening C A premature or critically ill infant D An infant with physiologic weight loss

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48

Clinical Case Cluster 48

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 20-year-old patient reports intentionally swallowing thirty 500-mg acetaminophen tablets two hours earlier. The time of ingestion is considered reliable. The patient has nausea but appears hemodynamically stable.

Question 1 of 6NPLEX-LAB-223

Diagnosis Foundational

Which laboratory test is most important for assessing toxicity from this single acute ingestion?

A Troponin alone B Urine acetaminophen screening C Serum amylase alone D A timed serum acetaminophen concentration

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 2 of 6NPLEX-LAB-224

Test selection and interpretation Intermediate

When should the first concentration generally be obtained after a known immediate-release ingestion?

A At or after four hours after ingestion B Thirty minutes after ingestion C One hour after ingestion D Twenty-four hours after ingestion

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 3 of 6NPLEX-LAB-225

Test selection and interpretation Intermediate

The concentration plots above the treatment line. Which antidote is indicated?

A Atropine B Naloxone C N-acetylcysteine D Flumazenil

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 4 of 6NPLEX-LAB-226

Clinical application Intermediate–advanced

In which situation is the Rumack–Matthew nomogram not reliably applicable?

A A single immediate-release ingestion at a known time B A reliable time of ingestion within the previous day C A four-hour concentration after one acute ingestion D Repeated supratherapeutic ingestion over several days

Reveal Answer Flag

Answer and Diagnostic Rationale

References

Question 5 of 6NPLEX-LAB-227

Clinical application Intermediate–advanced

Which laboratory panel is most useful for ongoing monitoring?

A Acetaminophen level, AST, ALT, INR, creatinine and glucose B Ferritin and vitamin B12 only C Rheumatoid factor and anti-CCP D TSH and free T4 only

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Question 6 of 6NPLEX-LAB-228

Safety and escalation Advanced

The patient develops severe acidosis, rising INR, hypoglycemia and hepatic encephalopathy. What is the next step?

A Discharge after completing the initial infusion B Urgent intensive care, toxicology and liver-transplant-centre assessment C Begin oral iron D Repeat testing in one month

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49

Clinical Case Cluster 49

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 61-year-old patient with bipolar disorder has taken lithium for several years. Hydrochlorothiazide was recently started for hypertension. After several days of vomiting and poor oral intake, the patient develops coarse tremor, diarrhea, unsteady gait and confusion.

Question 1 of 6NPLEX-LAB-229

Diagnosis Foundational

Which diagnosis is most likely?

A Acute iron poisoning B Serotonin syndrome C Neuroleptic malignant syndrome D Lithium toxicity

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Question 2 of 6NPLEX-LAB-230

Test selection and interpretation Intermediate

Which tests should be obtained promptly?

A Serum lithium, electrolytes and renal function B Stool ova and parasites C Serum lipase only D ANA and complement only

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Question 3 of 6NPLEX-LAB-231

Test selection and interpretation Intermediate

When should a routine trough lithium level generally be drawn?

A Immediately after swallowing the dose B Approximately 8–12 hours after the previous dose C Two hours after the dose D At a random time without documenting dosing

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Question 4 of 6NPLEX-LAB-232

Clinical application Intermediate–advanced

Which recent factor most likely increased this patient’s lithium concentration?

A Topical moisturizer use B Increased dietary fibre C Thiazide therapy combined with volume depletion D Vitamin C supplementation

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Question 5 of 6NPLEX-LAB-233

Clinical application Intermediate–advanced

Which statement about lithium concentrations is correct?

A Symptoms and laboratory values must be interpreted together B Clinical toxicity is impossible within the reported therapeutic range C Kidney function does not affect lithium clearance D Serum levels eliminate the need for clinical assessment

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Question 6 of 6NPLEX-LAB-234

Safety and escalation Advanced

The patient has severe neurologic toxicity, worsening renal failure and a markedly elevated lithium level. What is the most appropriate next step?

A Continue lithium at the same dose B Emergency toxicology or nephrology assessment for possible hemodialysis C Repeat the level after one month D Begin an herbal diuretic

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50

Clinical Case Cluster 50

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 3-year-old child lives in a house built before 1970 that is undergoing renovation. The child has pica, constipation, irritability and mild microcytic anemia. An initial finger-prick blood lead test is 24 µg/dL.

Question 1 of 6NPLEX-LAB-235

Diagnosis Foundational

What is the most appropriate next laboratory step?

A Order urine lead testing only B Diagnose severe lead poisoning without confirmation C Repeat another capillary test after one year D Obtain a confirmatory venous blood lead level

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Question 2 of 6NPLEX-LAB-236

Test selection and interpretation Intermediate

Why is the venous sample preferred for confirmation?

A It is less vulnerable to surface contamination B It measures only chronic exposure C It does not require laboratory analysis D It always produces a higher value

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Question 3 of 6NPLEX-LAB-237

Test selection and interpretation Intermediate

Which test best measures current lead exposure?

A Routine stool culture B Hair mineral analysis C Blood lead concentration D Serum calcium alone

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Question 4 of 6NPLEX-LAB-238

Clinical application Intermediate–advanced

What is the most important intervention after confirming an elevated level?

A Ignore the result if the child has no seizures B Give calcium alone without investigating the environment C Begin chelation in every child regardless of level D Identify and eliminate the lead source and arrange follow-up

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Question 5 of 6NPLEX-LAB-239

Clinical application Intermediate–advanced

Which associated condition should be assessed because it can increase gastrointestinal lead absorption?

A Hyperthyroidism B Hypercalcemia C Iron deficiency D Polycythemia

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Question 6 of 6NPLEX-LAB-240

Safety and escalation Advanced

The confirmed venous level is markedly elevated, and the child develops vomiting, ataxia and altered consciousness. What is the best next step?

A Begin a multivitamin and discharge B Emergency toxicology assessment for severe lead poisoning and possible chelation C Routine reassessment in six months D Repeat a finger-prick sample before treatment

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51

Clinical Case Cluster 51

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 64-year-old patient with gastrointestinal bleeding begins receiving packed red blood cells. Fifteen minutes after the transfusion starts, the patient develops fever, chills, severe back pain, dyspnea, hypotension and dark urine. The transfusion label and the patient identification band appear inconsistent.

Question 1 of 6NPLEX-LAB-241

Diagnosis Foundational

Which diagnosis is most likely?

A Acute hemolytic transfusion reaction B Febrile nonhemolytic transfusion reaction C Delayed hemolytic transfusion reaction D Transfusion-associated circulatory overload

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Question 2 of 6NPLEX-LAB-242

Test selection and interpretation Intermediate

What is the first action?

A Administer an antipyretic and continue B Stop the transfusion immediately and maintain intravenous access with normal saline C Discard the blood bag before notifying the blood bank D Slow the transfusion and reassess in 30 minutes

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Question 3 of 6NPLEX-LAB-243

Test selection and interpretation Intermediate

Which laboratory evaluation is most appropriate?

A Serum ferritin and folate only B Hemoglobin electrophoresis only C Direct antiglobulin test, repeat ABO typing, plasma hemolysis markers and urinalysis D D-dimer alone

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Question 4 of 6NPLEX-LAB-244

Clinical application Intermediate–advanced

Which practice most directly prevents ABO-incompatible transfusion?

A Warming every blood unit before administration B Bedside verification using two independent patient identifiers C Ordering a CBC after every transfusion D Routine premedication with acetaminophen

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Question 5 of 6NPLEX-LAB-245

Clinical application Intermediate–advanced

Which statement correctly distinguishes a type-and-screen from a crossmatch?

A A type-and-screen confirms compatibility with a specific donor unit B They are interchangeable terms C A type-and-screen determines ABO/Rh type and screens for unexpected antibodies; a crossmatch tests compatibility with a selected unit D A crossmatch identifies only the patient’s Rh type

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Question 6 of 6NPLEX-LAB-246

Safety and escalation Advanced

The patient develops oliguria and worsening shock. What is the best next step?

A Restart the same blood unit after symptoms improve B Give oral iron and repeat the CBC next month C Routine outpatient follow-up D Emergency critical-care management with blood-bank and transfusion-medicine consultation

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52

Clinical Case Cluster 52

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 72-year-old patient reports a new unilateral temporal headache, scalp tenderness, jaw fatigue while chewing and two brief episodes of monocular visual dimming. Examination shows a tender, reduced-pulse temporal artery. Test Result ESR 78 mm/h CRP 64 mg/L Platelets 512 × 10⁹/L Hemoglobin 10.8 g/dL

Question 1 of 6NPLEX-LAB-247

Diagnosis Foundational

Which diagnosis is most concerning?

A Giant-cell arteritis B Tension-type headache C Migraine with aura D Trigeminal neuralgia

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Question 2 of 6NPLEX-LAB-248

Test selection and interpretation Intermediate

Which statement about ESR and CRP is most accurate?

A A normal ESR always excludes giant-cell arteritis B CRP is unaffected by acute inflammation C ESR changes more rapidly than CRP D CRP generally rises and falls faster than ESR

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Question 3 of 6NPLEX-LAB-249

Test selection and interpretation Intermediate

Which factor can independently elevate the ESR?

A Severe hypofibrinogenemia B Polycythemia C Anemia D Spherocytosis

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Question 4 of 6NPLEX-LAB-250

Clinical application Intermediate–advanced

What is the most appropriate immediate management principle when visual ischemic symptoms are present?

A Delay treatment until biopsy results return B Begin urgent glucocorticoid treatment and arrange specialist assessment C Repeat ESR in three months before acting D Treat with an NSAID alone

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Question 5 of 6NPLEX-LAB-251

Clinical application Intermediate–advanced

Which test can help support the diagnosis without replacing clinical judgment?

A Temporal-artery ultrasonography or biopsy B Serum amylase C Fecal occult-blood testing D D-dimer alone

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Question 6 of 6NPLEX-LAB-252

Safety and escalation Advanced

Which interpretation is safest if ESR is normal but the patient has classic jaw claudication and visual symptoms?

A The disease is excluded B The symptoms are due to aging C No further assessment is needed unless fever develops D Urgent evaluation is still required because normal inflammatory markers do not completely exclude disease

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53

Clinical Case Cluster 53

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 34-year-old patient develops fever, cramping abdominal pain and frequent bloody diarrhea after returning from travel. The patient is hemodynamically stable and has not recently taken antibiotics.

Question 1 of 6NPLEX-LAB-253

Diagnosis Foundational

Which stool investigation is most appropriate initially?

A Stool bacterial culture or a validated enteric molecular panel B Twenty-four-hour fecal fat collection C Stool pH only D Fecal occult-blood testing alone

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Question 2 of 6NPLEX-LAB-254

Test selection and interpretation Intermediate

Which specimen is best?

A A formed stool collected several days after symptoms resolve B Fresh diarrheal stool placed promptly in the correct transport container C A specimen contaminated with urine D A swab of toilet water

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Question 3 of 6NPLEX-LAB-255

Test selection and interpretation Intermediate

When is ova-and-parasite testing most appropriate?

A Every episode of diarrhea lasting less than 24 hours B Only after a positive fecal immunochemical test C Persistent diarrhea, relevant travel or exposure risk, or suspected parasitic infection D Only when constipation is present

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Question 4 of 6NPLEX-LAB-256

Clinical application Intermediate–advanced

Which patient should generally be tested for Clostridioides difficile?

A A patient whose diarrhea resolved one month ago B A patient with new unexplained clinically significant diarrhea and a relevant healthcare or antibiotic exposure C An asymptomatic household contact D A patient with formed stool and no diarrhea

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Question 5 of 6NPLEX-LAB-257

Clinical application Intermediate–advanced

Which marker is most useful for detecting intestinal inflammation rather than identifying a specific pathogen?

A Urine nitrite B Haptoglobin C Fecal calprotectin D Serum sodium

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Question 6 of 6NPLEX-LAB-258

Safety and escalation Advanced

The patient develops severe abdominal pain, hypotension and peritoneal signs. What is the best next step?

A Begin an elimination diet and reassess in one month B Wait for the stool culture before referral C Repeat the stool sample after symptoms improve D Emergency hospital assessment for severe colitis or perforation

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54

Clinical Case Cluster 54

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 58-year-old patient presents with fever, rigors, confusion and hypotension. Pneumonia is suspected. Intravenous antibiotics are being prepared.

Question 1 of 6NPLEX-LAB-259

Diagnosis Foundational

How should blood cultures be obtained?

A At least two appropriately filled culture sets from separate venipuncture sites before antibiotics when this does not delay treatment B A single swab from intact skin C After completing the full antibiotic course D One bottle from an existing intravenous line only

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Question 2 of 6NPLEX-LAB-260

Test selection and interpretation Intermediate

Which statement is most important in septic shock?

A Repeat cultures weekly before beginning treatment B Use only oral antibiotics until the organism is identified C Wait for culture results before giving antibiotics D Obtain cultures promptly, then start empiric therapy without clinically important delay

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Question 3 of 6NPLEX-LAB-261

Test selection and interpretation Intermediate

Which sputum finding suggests a poor-quality lower-respiratory specimen?

A Purulent material from a deep cough B A predominant organism on Gram stain C Numerous squamous epithelial cells D Many neutrophils with few squamous epithelial cells

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Question 4 of 6NPLEX-LAB-262

Clinical application Intermediate–advanced

Which specimen is preferred for suspected deep anaerobic wound infection?

A A urine specimen B Aspirated fluid or tissue obtained from the infected depth and transported anaerobically C A swab of intact surrounding skin D A superficial swab exposed to air

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Question 5 of 6NPLEX-LAB-263

Clinical application Intermediate–advanced

What does the minimum inhibitory concentration represent?

A The lowest antimicrobial concentration that prevents visible growth under standardized conditions B The patient’s serum drug concentration C The highest antimicrobial concentration that permits visible growth D The number of organisms in the original specimen

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Question 6 of 6NPLEX-LAB-264

Safety and escalation Advanced

Only one of four blood-culture bottles grows coagulase-negative staphylococci, and the patient has no intravascular device. What is the best interpretation?

A Definite endocarditis B A viral infection C Proof that antibiotics are unnecessary D Probable contamination, interpreted with the clinical picture and repeat cultures when needed

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55

Clinical Case Cluster 55

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 49-year-old patient develops acute shoulder pain and weakness after lifting a heavy object. Active abduction is markedly limited, but passive range of motion is relatively preserved. There is no deformity or neurovascular deficit.

Question 1 of 6NPLEX-LAB-265

Diagnosis Foundational

Which diagnosis is most likely?

A Full-thickness rotator-cuff tear B Adhesive capsulitis C Septic arthritis D Cervical myelopathy

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Question 2 of 6NPLEX-LAB-266

Test selection and interpretation Intermediate

Which imaging test can dynamically evaluate the rotator cuff without ionizing radiation?

A Noncontrast head CT B Bone scan C Musculoskeletal ultrasonography D Abdominal radiography

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Question 3 of 6NPLEX-LAB-267

Test selection and interpretation Intermediate

Which limitation of ultrasound is most relevant?

A It exposes the patient to substantial ionizing radiation B It always requires intravenous contrast C It cannot visualize any tendon D It is less suitable for deep intra-articular structures and is operator dependent

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Question 4 of 6NPLEX-LAB-268

Clinical application Intermediate–advanced

Which finding would make MRI particularly useful?

A Need to measure blood pressure B Concern for labral injury or complex deep soft-tissue pathology C Evaluation of a superficial cyst only D Screening for gallstones

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Question 5 of 6NPLEX-LAB-269

Clinical application Intermediate–advanced

What is the usual initial imaging study after significant acute shoulder trauma when fracture is possible?

A Plain radiographs B HIDA scan C PET-CT D EEG

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Question 6 of 6NPLEX-LAB-270

Safety and escalation Advanced

The shoulder becomes hot and swollen, and the patient develops fever with severe pain on passive motion. What is the best next step?

A Begin strengthening exercises immediately B Routine ultrasound in six months C Urgent assessment and joint aspiration for suspected septic arthritis D Reassure the patient that this is a tendon tear

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56

Clinical Case Cluster 56

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A farm worker is brought to the emergency department after pesticide exposure. The patient has diaphoresis, salivation, lacrimation, vomiting, diarrhea, pinpoint pupils, wheezing, bradycardia and muscle fasciculations.

Question 1 of 6NPLEX-LAB-271

Diagnosis Foundational

Which toxidrome is present?

A Cholinergic toxidrome B Sedative-hypnotic toxidrome C Anticholinergic toxidrome D Sympathomimetic toxidrome

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Question 2 of 6NPLEX-LAB-272

Test selection and interpretation Intermediate

Which laboratory test can support organophosphate exposure?

A D-dimer B Serum ferritin C Plasma butyrylcholinesterase or red-cell acetylcholinesterase activity D Direct antiglobulin test

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Question 3 of 6NPLEX-LAB-273

Test selection and interpretation Intermediate

What is the first decontamination priority?

A Apply an occlusive dressing over contaminated skin B Delay decontamination until laboratory confirmation C Induce vomiting D Protect staff with appropriate personal protective equipment and remove contaminated clothing

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Question 4 of 6NPLEX-LAB-274

Clinical application Intermediate–advanced

Which medication treats life-threatening muscarinic manifestations such as bronchorrhea and bradycardia?

A Methylene blue B Atropine C Naloxone D Flumazenil

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Question 5 of 6NPLEX-LAB-275

Clinical application Intermediate–advanced

What is the role of pralidoxime?

A It is an oral chelator for lead B It causes intentional cholinergic stimulation C It replaces atropine for bronchorrhea D It reactivates acetylcholinesterase when administered before irreversible aging and is especially useful for nicotinic weakness

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Question 6 of 6NPLEX-LAB-276

Safety and escalation Advanced

The patient has copious secretions and respiratory muscle weakness. What is the best next step?

A Discharge after skin washing B Immediate airway support, atropine and toxicology-guided antidotal treatment C Wait for cholinesterase results D Administer a beta blocker alone

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57

Clinical Case Cluster 57

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 33-year-old patient and a 35-year-old partner have had regular unprotected intercourse for 14 months without conception. Menstrual cycles occur every 29–31 days. Neither partner has undergone fertility testing.

Question 1 of 6NPLEX-LAB-277

Diagnosis Foundational

Which principle is most appropriate?

A Evaluate both partners concurrently B Evaluate only the partner who menstruates C Delay all evaluation until five years have passed D Begin assisted reproduction without diagnostic assessment

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Question 2 of 6NPLEX-LAB-278

Test selection and interpretation Intermediate

Which is the usual initial male-factor test?

A Serum troponin B Urine culture C Semen analysis D Fecal calprotectin

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Question 3 of 6NPLEX-LAB-279

Test selection and interpretation Intermediate

An initial semen analysis is abnormal. What is the best next step?

A Ignore the result if libido is normal B Repeat the analysis under standardized collection conditions and assess clinical context C Diagnose permanent infertility from one sample D Order a brain CT immediately

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Question 4 of 6NPLEX-LAB-280

Clinical application Intermediate–advanced

Which test can provide evidence that ovulation has occurred?

A Serum alkaline phosphatase B D-dimer C Direct antiglobulin test D Appropriately timed serum progesterone

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Question 5 of 6NPLEX-LAB-281

Clinical application Intermediate–advanced

Which investigation assesses tubal patency?

A DXA scanning B Hysterosalpingography C Spirometry D Electroencephalography

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Question 6 of 6NPLEX-LAB-282

Safety and escalation Advanced

Which statement about anti-Müllerian hormone is most accurate?

A It diagnoses every cause of anovulation B It directly proves natural fertility C It estimates ovarian reserve but does not by itself predict spontaneous conception D It confirms tubal patency

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58

Clinical Case Cluster 58

6 questions · Laboratory & Imaging Diagnosis

Blueprint domain revealed after completion Reviewed July 2026

Clinical Case

A 69-year-old patient with diabetes and chronic kidney disease presents with abdominal pain and fever. Contrast-enhanced CT is being considered. The most recent eGFR is 28 mL/min/1.73 m², and the patient takes metformin. There is no immediate hemodynamic instability.

Question 1 of 6NPLEX-LAB-283

Diagnosis Foundational

Which laboratory value is most relevant when assessing renal risk before iodinated contrast?

A TSH B Hemoglobin A1c alone C Serum amylase alone D Estimated glomerular filtration rate

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Question 2 of 6NPLEX-LAB-284

Test selection and interpretation Intermediate

Which principle is most appropriate?

A Use double the contrast dose to improve image quality B Balance diagnostic benefit against renal risk and use preventive measures or alternatives when appropriate C Rely only on the patient’s age D Cancel every contrast-enhanced examination in chronic kidney disease

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Question 3 of 6NPLEX-LAB-285

Test selection and interpretation Intermediate

Which modality can often evaluate biliary obstruction without iodinated contrast?

A Ultrasonography B Spirometry C Plain skull radiography D EEG

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Question 4 of 6NPLEX-LAB-286

Clinical application Intermediate–advanced

Which statement about metformin is most accurate?

A Metformin must always be permanently discontinued before any imaging B Metformin itself causes contrast nephrotoxicity C No renal assessment is ever required D Management depends on kidney function and acute kidney injury risk because metformin accumulation during renal failure can increase lactic-acidosis risk

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Question 5 of 6NPLEX-LAB-287

Clinical application Intermediate–advanced

Which contrast-related history requires special planning but does not automatically prohibit a necessary study?

A A previous immediate allergic-like reaction to iodinated contrast B A remote ankle sprain C Seasonal allergic rhinitis alone D Iron-deficiency anemia

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Question 6 of 6NPLEX-LAB-288

Safety and escalation Advanced

During contrast administration the patient develops wheezing, hypotension and generalized urticaria. What is the best next step?

A Give oral iron B Continue imaging and observe C Treat immediately as anaphylaxis and activate emergency support D Wait for a serum tryptase result before treatment

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