Hypertension, hyperreninemia and a solitary renal cyst in an adolescent.

Solitary renal cysts associated with hypertension and documented hyperreninemia are relatively uncommon. A 13 year old boy with these findings is described (pressure 160/120 mm Hg). Contrast studies of the urinary tract and arteriography with selective renal vein sampling demonstrated a solitary cyst in the right kidney. The ratio of plasma renin activity in the right renal vein to left renal vein (RRV:LRV) was 2.35:1. After drainage of the cyst, there was a marked reduction in both systolic and diastolic pressures (126/84 mm Hg). Hypertension has not recurred during 14 months' follow-up.