Hypertension in an Adult with Unilateral Renal Dysplasia

: We report a 29-year-old Japanese female with severe hypertension and unilateral renal dysplasia, which is rarely found in adults. The involved kidney was surgically removed and then the blood pressure fell to borderline levels without any changes in plasma renin activity or plasma aldosterone concentration. Histological examinations revealed typical renal dysplasia without hyperplasia of the juxtaglomerular apparatus. Unilateral renal dysplasia may be a cause of secondary hypertension in adults, though the mechanisms are still unknown.