A 43-year-old man is hospitalized with hypovolemic shock

Welcome back to MedSmarter’s USMLE Style Question of the Week. Here’s the breakdown of another high-yield Renal question for those preparing for your USMLE Step 1 or just to gain some knowledge. As always you want to begin by reading the last sentence of the vignette first to get an understanding of what the question is asking for.
Question Break Down of the Week:
A 43-year-old man is hospitalized with hypovolemic shock after massive blood loss in a motor vehicle accident. On the patient’s second day in the hospital, his blood urea nitrogen (BUN) and creatinine levels begin to rise and he develops pitting edema to his knees. A subsequent urinalysis shows numerous granular casts. Which of the following is the most appropriate treatment?
A) Broad-spectrum antibiotics
B) Corticosteroids
C) Fluids and dialysis
D) Angioplasty
E) Use of ultrasound to remove the blockage
The correct answer choice is C. The patient is presenting with acute tubular necrosis (ATN) as a result of hypovolemic shock caused by massive blood loss. The elevated BUN and creatinine levels, pitting edema, and presence of numerous granular casts in the urinalysis are all indicative of ATN. The appropriate treatment is to correct the fluid loss and electrolyte imbalance by starting fluid replacement with crystalloid solutions and blood products. If there is no immediate improvement in renal function, dialysis may be necessary. Antibiotics (answer choice A) are not indicated in the treatment of ATN as it is not caused by an infection. Corticosteroids (answer choice B) may be used for acute renal failure, but not in the case of hypovolemia-induced ATN. Angioplasty (answer choice D) and the use of ultrasound to remove blockages (answer choice E) are not appropriate treatments for ATN.
Did you think the answer was different?
Did you think that the correct answer choice was other than C? You can view this video for a deeper discussion of why A, B, D, and E are not the correct answer choices.
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