Newborn with a cystic kidney on prenatal ultrasound Sagittal US of the right kidney (above) shows it to contain multiple cysts of various sizes that do not communicate. There is also a paucity of renal parenchyma. Sagittal US of the right kidney 1 month later (below) again shows multiple cysts of various sizes that do not communicate and interval decrease in the amount of renal parenchyma present. The diagnosis was multicystic dysplastic kidney.