Multicystic Dysplastic Kidney

  • Etiology: due to pelvicalyceal / ureteric atresia = most severe form of congenital ureteropelvic junction obstruction
  • Imaging: unilateral, nonfunctional renal mass where kidney is replaced by multiple cysts (=dilated calyces) of various sizes that don’t communicate, absent renal parenchyma
  • Clinical: second most common cause of renal masses in neonates, involutes spontaneously, associated with contralateral vesicoureteral reflux or ureteropelvic junction obstruction (15%)

Cases of Multicystic Dysplastic Kidney

US of multicystic dysplastic kidney
Sagittal US images of the right kidney show it to be larger than the left kidney and to have multiple cysts of varying sizes that do not communicate.