Localized cystic disease of the kidney: a rare cause of hypertension in a young adult.

Localized cystic disease of kidney (LCDK) is a rare, non-familial, non-progressive renal disorder that is not associated with cysts or disorders in other organs. Only a few cases have been reported in the literature. While this condition is morphologically identical to the autosomal dominant form of polycystic kidney disease, it is not inherited and is not associated with significant deterioration of renal function. We present a case of a 16-year-old male patient who suffered from hypertension for over two years. On imaging we found several, variable-sized cysts in the upper half of the right kidney. The left kidney and lower segment of the right kidney were normal. Selective renal vein catheterization and sampling showed markedly elevated renin level in the right upper segmental vein (92 pg/ml, normal value: 11-33 pg/ml). The patient underwent a right upper heminephrectomy and histopathology was suggestive of LCDK. After surgery, the patient's blood pressure returned to normal levels without any need of antihypertensive medication and he is under follow-up on outpatient basis for the past two years.