Multicystic Dysplastic Kidney

Multicystic dysplastic kidney (MCDK) denotes a kidney in which the renal parenchyma is replaced by numerous smooth-walled cysts of varying size that do not communicate with a renal pelvis and are surrounded by echogenic cortex, with an atretic ureter. It is a form of severe dysplasia that typically results in a nonfunctioning kidney. It is bilateral in approximately 25% of cases, usually conferring a lethal prognosis. Unilateral MCDK is associated with contralateral renal anomalies in 30% to 40% of cases, most commonly vesicoureteral reflux or ureteropelvic junction obstruction. Nonrenal anomalies are also frequent, occurring in approximately 25% of cases, and the finding of an associated anomaly significantly increases the fetal aneuploidy risk.