Acute renal failure secondary to angiotensin II receptor blockade in a patient with bilateral renal artery stenosis.

A 54-year-old man with diabetes mellitus, peripheral vascular disease, and hypertension was admitted to the hospital for an acute exacerbation of chronic heart failure. Therapy with intravenous furosemide and oral losartan 100 mg twice/day was begun. Ten days later, the patient's blood urea nitrogen and serum creatinine levels rose and peaked at 110 and 6.0 mg/dl, respectively. His serum potassium level increased to 5.7 mg/dl, urine output dropped to 400 ml over 24 hours, and mental status changes occurred. Magnetic resonance angiography revealed bilateral renal artery stenosis. After losartan was discontinued and hemodialysis was performed for 3 consecutive days, the patient's renal function returned to his baseline level. Reports in the medical literature reinforce the importance of recognizing that angiotensin-converting enzyme inhibitors should be used with caution in patients with bilateral renal artery stenosis. However, the literature is not as definitive about using of angiotensin II receptor blockers (ARBs) in these patients. Our patient's experience suggests that ARBs should be used with caution in patients with bilateral renal artery stenosis. Clinicians should be aware that renal failure might occur when using ARBs in these patients.