Chronic Kidney Disease USMLE Step 1 Practice Question
A 31-year-old man presents with progressive weakness and fatigue. Vital signs: BP 138/88 mmHg, HR 92/min, RR 16/min, Temp 37°C, SpO2 98%. Laboratory studies reveal normal anion gap metabolic acidosis, serum potassium 3.2 mEq/L, serum glucose 95 mg/dL, urinalysis with glucosuria, phosphaturia, and aminoaciduria. Serum creatinine is normal. There is no proteinuria. Which portion of the nephron is primarily affected?
Answer choices
- AProximal tubuleCorrect answer
- BCollecting duct principal cell
- CThick ascending limb
- DDistal convoluted tubule
- EMacula densa
- FJuxtaglomerular apparatus
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