ABSTRACT
Congenital megacalyces is a congenital renal disease characterized by hypoplasia of the medulla and a non-obstructive dilatation of the calyces. More than 100 cases have been reported in the literature after first described by Puigvert in 1963, but it has been reported only three cases (two cases of adults and one case of child) in the literatures in Korea. The etiology of the congenital megacalyces is unknown. Renal pelvis and ureter are mostly normal in size and there is no urinary obstruction or reflux. Renal medulla of congenital megacalyces is thinner than that of normal kidney but renal cortex retains its normal thickness and function. This is features that help to distinguish megacalyces from obstructive atropy. The calyces are polygonal in shape and the majority of kidney with megacalyces have increased number of calyces. Since congenital megacalyces is a non-progressive lesion, it is important to recognize the clinical entity and avoid unnecessary surgery. We report one case of congenital megacalyces without urinary obstruction or reflux with a brief review of related literatures.