Electrolyte Disorders USMLE Step 1 Practice Question
A 38-year-old man with chronic diarrhea presents with weakness and muscle cramps. Vital signs: BP 128/82 mmHg, HR 102 bpm, RR 18/min, temp 37.2°C, SpO2 98% on room air. Laboratory findings reveal serum potassium 3.1 mEq/L, serum bicarbonate 32 mEq/L, and serum chloride 94 mEq/L. Urine potassium is 12 mEq/24h and urine chloride 8 mEq/24h. Serum creatinine is normal. Which diagnosis best explains these findings?
Answer choices
- ADiabetic ketoacidosis
- BAcute respiratory alkalosis
- CPrimary hyperaldosteronism
- DMetabolic alkalosis with contraction and hypochloremiaCorrect answer
- ERenal tubular acidosis type 2
- FHypokalemic periodic paralysis due to thyroid dysfunction
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