Question 1: Chest Pain in a Young Adult
A 27-year-old man presents with sharp chest pain that worsens with deep breaths and improves when sitting up. He had a flu-like illness a week ago. On auscultation, you hear a pericardial friction rub. ECG shows diffuse ST-segment elevations.
What is the best initial treatment?
A. Aspirin + colchicine
B. IV heparin + beta-blockers
C. High-dose corticosteroids
D. Thrombolysis with alteplase
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✅ Answer: A. Aspirin + colchicine
Acute pericarditis → Classic pleuritic pain, viral prodrome, diffuse ST elevations
Treatment: NSAIDs (aspirin/ibuprofen) + colchicine
❌ Why not others?
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MI (B, D) → ST elevations would be localized + reciprocal changes.
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Steroids (C) → Only used if NSAIDs fail (high recurrence risk).
Question 2: Post-Op Shortness of Breath
A 56-year-old woman, post-op day 3 from a total hip replacement, suddenly develops shortness of breath, pleuritic chest pain, and tachycardia (HR 110). Oxygen saturation is 89% on room air. ECG shows sinus tachycardia with no ST changes.
What is the most likely diagnosis?
A. Atelectasis
B. Pneumonia
C. Pulmonary embolism (PE)
D. Myocardial infarction
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✅ Answer: C. Pulmonary embolism (PE)
Post-op + sudden dyspnea + tachycardia + hypoxia → Classic PE
Best initial test: CT pulmonary angiography (CTPA)
Treatment: Anticoagulation (heparin)
❌ Why not others?
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Atelectasis (A) → Causes mild hypoxia, no pleuritic pain/tachycardia.
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Pneumonia (B) → No fever, cough, or lung infiltrates.
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MI (D) → No ST changes or cardiac risk factors.
Question 3: Hypertension in a Young Woman
A 32-year-old woman has refractory hypertension despite three antihypertensive medications. She also has hypokalemia and muscle weakness. Labs show:
Plasma aldosterone: High
Plasma renin: Low
What is the most likely diagnosis?
A. Cushing’s syndrome
B. Primary hyperaldosteronism (Conn’s syndrome)
C. Pheochromocytoma
D. Renal artery stenosis
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✅ Answer: B. Primary hyperaldosteronism (Conn’s syndrome)
Resistant HTN + hypokalemia + high aldosterone/low renin → Classic for Conn’s syndrome.
Confirmatory test: Aldosterone suppression test
Treatment: Spironolactone (aldosterone antagonist)
❌ Why not others?
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Cushing’s (A) → Would have moon face, striae, hyperglycemia.
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Pheo (C) → Causes paroxysmal HTN, sweating, palpitations.
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Renal artery stenosis (D) → Would have high renin, high aldosterone.
Question 4: Hyperpigmentation & Fatigue
A 45-year-old woman has fatigue, weight loss, hypotension, nausea, and hyperpigmentation on her gums and elbows. Lab results:
Na⁺: 126 mEq/L
K⁺: 5.7 mEq/L
Glucose: 68 mg/dL
ACTH: High
What is the confirmatory test?
A. Serum cortisol levels
B. Cosyntropin (ACTH stimulation) test
C. Dexamethasone suppression test
D. Plasma metanephrines
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✅ Answer: B. Cosyntropin (ACTH stimulation) test
Primary adrenal insufficiency (Addison’s disease) → Hyperpigmentation + low cortisol + high ACTH
Treatment: Hydrocortisone + fludrocortisone
❌ Why not others?
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Serum cortisol (A) → Low but not confirmatory.
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Dexamethasone test (C) → Used for Cushing’s, not Addison’s.
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Metanephrines (D) → Used for pheochromocytoma.
Question 5: Diabetic Ketoacidosis (DKA)
A 22-year-old man with type 1 diabetes presents with nausea, vomiting, confusion, and rapid breathing. Lab results:
Glucose: 450 mg/dL
pH: 7.2
HCO₃⁻: 12 mEq/L
Urine: Positive for ketones
What is the next step in management?
A. IV fluids + IV insulin
B. Sodium bicarbonate
C. Glucose infusion
D. Metformin
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✅ Answer: A. IV fluids + IV insulin
DKA treatment: 1️⃣ IV fluids, 2️⃣ IV insulin, 3️⃣ K⁺ replacement if low
❌ Why not others?
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Bicarbonate (B) → Only if pH < 6.9.
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Glucose (C) → Used later to prevent hypoglycemia.
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Metformin (D) → Used for type 2 DM, not DKA.
Bonus Questions (6-10) – Quick Cases
Question 6:
A 68-year-old smoker has a cough, weight loss, and SIADH (hyponatremia, low serum osmolality).
✅ Answer: Small cell lung cancer (SCLC)
Question 7:
A 5-year-old boy presents with dark urine, facial swelling, and recent strep throat.
✅ Answer: Post-streptococcal glomerulonephritis (PSGN)
Question 8:
A 56-year-old diabetic presents with fever, headache, and nuchal rigidity. CSF shows low glucose, high WBCs, and gram-positive diplococci.
✅ Answer: Streptococcus pneumoniae (pneumococcal meningitis)
Question 9:
A 65-year-old man has progressive memory loss, personality changes, and myoclonus. EEG shows sharp wave complexes.
✅ Answer: Creutzfeldt-Jakob disease (CJD)
Question 10:
A 36-year-old woman has episodic headaches, sweating, and palpitations. BP spikes to 190/110. What test should be ordered first?
✅ Answer: Plasma metanephrines (Pheochromocytoma workup)
Final Thoughts
💡 Clinical reasoning is a must.
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