Acute Kidney Injury USMLE Step 1 Practice Question
A 68-year-old man with a history of congestive heart failure presents with worsening dyspnea and lower extremity edema. He recently stopped taking his medications. Physical examination reveals bilateral coarse crackles on inspiration. Serum creatinine is 2.8 mg/dL (baseline 1.1 mg/dL). Urinalysis shows no casts. Which of the following sets of laboratory findings (BUN:Cr ratio, Urine Na, Urine Osmolality, FENa) is most consistent with this patient's condition?
Answer choices
- ABUN:Cr 10:1, Urine Na 54 mEq/L, Urine Osm 290 mOsm/kg, FENa 3.2%
- BBUN:Cr 28:1, Urine Na 8 mEq/L, Urine Osm 620 mOsm/kg, FENa 0.4%Correct answer
- CBUN:Cr 18:1, Urine Na 35 mEq/L, Urine Osm 320 mOsm/kg, FENa 1.5%
- DBUN:Cr 22:1, Urine Na 45 mEq/L, Urine Osm 310 mOsm/kg, FENa 2.1%
- EBUN:Cr 15:1, Urine Na 60 mEq/L, Urine Osm 600 mOsm/kg, FENa not applicable
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