Diabetes Mellitus USMLE Step 1 Practice Question
A 44-year-old woman with a 3-year history of hypertension poorly controlled on lisinopril presents with progressive muscle cramps and fatigue. Vital signs show BP 168/102 mmHg, HR 88 bpm, RR 16, temp 37°C, SpO2 98%. Labs reveal serum potassium 2.8 mEq/L, bicarbonate 32 mEq/L, suppressed plasma renin activity 0.3 ng/mL/hr, and elevated aldosterone 28 ng/dL. Urinary sodium is normal. Which diagnosis best explains these findings?
Answer choices
- AConn syndromeCorrect answer
- BPrimary adrenal insufficiency
- CSIADH
- DDiabetic ketoacidosis
- EPheochromocytoma
- FRenovascular hypertension from renal artery stenosis
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