Gentamicin is being administered to a 65-year-old woman for an abdominal infection complicated by multidrug-resistant organisms. The patient's urine output decreases noticeably after a week of treatment, and serum creatinine rises to 2.3 mg/dL. She has no history of kidney disease, and her baseline kidney function was normal prior to starting therapy. For the past 24 hours, the patient has been afebrile. The blood pressure is 130/80 mm Hg, and the pulse rate is 80 bpm. The examination reveals moist mucous membranes. There is nothing rash. Urinalysis results are as follows: Fractional excretion of sodium is 2%. Histologic examination of the patient's kidneys would most likely show which of the following?

Question

Gentamicin is being administered to a 65-year-old woman for an abdominal infection complicated by multidrug-resistant organisms. The patient's urine output decreases noticeably after a week of treatment, and serum creatinine rises to 2.3 mg/dL. She has no history of kidney disease, and her baseline kidney function was normal prior to starting therapy. For the past 24 hours, the patient has been afebrile. The blood pressure is 130/80 mm Hg, and the pulse rate is 80 bpm. The examination reveals moist mucous membranes. There is nothing rash. Urinalysis results are as follows:  Fractional excretion of sodium is >2%.  Histologic examination of the patient's kidneys would most likely show which of the following?

Quizplus · Accepted Answer

Eductional Objective: Aminoglycosides pass through the glomerulus and concentrate in the renal tubules, causing proximal tubular injury and acute tubular necrosis. Histologically, this is seen as focal tubular epithelial necrosis, often with extensive granular casts that obstruct the tubular lumen and cause basement membrane rupture.

Gentamicin Is Being Administered to a 65-Year-Old Woman for an Abdominal