Curable Hypertension with Unilateral Hydronephrosis

Abstract

Among eight patients with unilateral hydronephrosis and hypertension, peripheral plasma renin activity was normal in seven and borderline high in one. Four patients had hydronephrotic/contralateral kidney renin ratios of > 1.5, suggesting excessive renin release from the diseased kidney, and ratios between contralateral kidney and peripheral blood of < 1.2, indicating suppressed renin production in the contralateral kidney. Nephrectomy normalized blood pressure in each of these patients. Two patients had hydronephrotic/contralateral kidney renin ratios of ≤ 1.3 or contralateral kidney/periphery ratios of > 1.2, suggesting ischemia of the contralateral kidney; pyeloplasty or nephrectomy, or both, failed to improve the hypertension. Postoperative changes in blood pressure correlated with changes in peripheral renin (r = 0.90; P < 0.01). These data suggest that hypertension associated with unilateral hydronephrosis is partly renin-dependent; and renal vein renin values are helpful in selecting patients for surgery.