Acute Kidney Injury USMLE Step 1 Practice Question
A 72-year-old woman admitted with community-acquired pneumonia receives gentamicin therapy. On hospital day 3, she develops oliguria with urine output of 800 mL/day. Vital signs show BP 128/76 mmHg, HR 92/min, RR 20/min, temperature 37.2°C, and SpO2 98% on room air. Serum creatinine rises from 0.9 to 2.1 mg/dL. Urinalysis reveals muddy brown granular casts and tubular epithelial cells. FENa is 3.2%. Urine osmolality is 450 mOsm/kg. Which of the following is the most likely diagnosis?
Answer choices
- AAminoglycoside-induced acute tubular necrosisCorrect answer
- BPrerenal acute kidney injury
- CContrast-induced nephropathy
- DAllergic glomerulonephritis
- EAcute interstitial nephritis from gentamicin
- FPostinfectious glomerulonephritis secondary to bacterial pneumonia
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