This autopsy of a fetus reveals very big abnormal kidneys, there is a little to no kidney tissues here, its formed by many fluid filled cysts, this condition is called Multicystic dysplastic kidney (MCDK), it results from the malformation of the kidney during fetal development. Multicystic dysplastic kidney is a common type of renal cystic disease, and it is a cause of an abdominal mass in infants.