Reversible malignant hypertension and azotemia due to urethral stricture.

A previously normotensive 24-year-old black man developed malignant hypertension and azotemia. The patient was found to have bladder outlet obstruction due to urethral stricture. Transurethral dilation resulted in brisk improvement in renal function and rapid lowering of blood pressure in association with minimal diuresis. On follow-up one year later, while he was not receiving medications, the blood pressure was 120/70 mm Hg and the creatinine clearance was 150 ml/min. A kidney biopsy specimen showed minimal residual pathologic abnormalities in the renal arteries and arterioles. The renin-angiotensin system was probably involved in the maintenance of the hypertension, in view of the elevated peripheral plasma renin activity on admission. This represents a rare case of hypertension due to urethral stricture. Despite rapid progression to azotemic malignant hypertension, urethral dilation restored the blood pressure and renal function to normal.