Nonoliguric acute renal failure after captopril therapy

Area of Science:

• Nephrology
• Pharmacology
• Internal Medicine

Background:

• Renovascular hypertension is a significant risk factor for kidney disease.
• Angiotensin-converting enzyme inhibitors like captopril are commonly used to manage hypertension.

Observation:

• A patient with severe renovascular hypertension developed nonoliguric acute renal failure after initiating captopril therapy.
• Urine output remained adequate (1,640–2,260 mL/24 hr) despite rising serum creatinine (2.3–8.3 mg/dL).

Findings:

• No evidence of renal hypoperfusion or interstitial nephritis was found.
• The acute renal failure was attributed to the nephrotoxic effect of captopril on chronically compromised kidneys.

Implications:

• This case highlights a potential, previously unreported adverse effect of captopril.
• Prompt drug withdrawal led to rapid improvement in renal function, emphasizing the importance of vigilant monitoring in susceptible patients.