Acute Kidney Injury USMLE Step 1 Practice Question
A 42-year-old male construction worker is extricated from a collapsed building after being trapped under heavy rubble for 6 hours. He sustained severe crush injuries to both lower extremities. On presentation to the emergency department, he is alert and oriented with the following findings: Vitals: BP 92/58 mmHg, HR 118 bpm, RR 22/min
Labs:
- Serum creatinine: 5.1 mg/dL (baseline 1.0 mg/dL)
- Potassium: 7.2 mEq/L
- Calcium: 7.1 mg/dL
- Phosphate: 8.9 mg/dL
- CK: 45,000 IU/L
- Urinalysis: 3+ blood, no RBCs on microscopy, muddy brown casts present Which of the following is the most likely diagnosis?
Answer choices
- AAcute glomerulonephritis secondary to crush injury
- BRhabdomyolysis-induced acute kidney injuryCorrect answer
- CDisseminated intravascular coagulation with acute tubular necrosis
- DHemolytic uremic syndrome
- EAcute interstitial nephritis from nephrotoxic medications
- FPrerenal acute kidney injury from hypovolemia alone
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