Acute Kidney Injury USMLE Step 1 Practice Question
A 74 year old man presents with suprapubic discomfort, nocturia, and weak urinary stream. Over the last day he has had difficulty voiding. Laboratory studies show rising BUN and creatinine. Bedside ultrasound reveals bilateral hydronephrosis and a distended bladder. Which of the following is the most likely cause of his acute kidney injury?
Answer choices
- AAutoimmune injury to the renal interstitium
- BIncreased hydrostatic pressure proximal to urinary tract obstructionCorrect answer
- CAcute ischemic necrosis of tubular epithelium
- DSelective efferent arteriolar vasodilation
- EImmune complex deposition in the glomeruli
- FTubular reabsorption of filtered sodium and water
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