Multicystic dysplasia in the upper component of the complete duplex kidney

Four cases of neonatal multicystic dysplasia involving the upper part of a complete duplex kidney are presented. This malformation, suspected on antenatal ultrasound examination, was confirmed by postnatal IVP and ultrasound. This emphasizes the need to perform an IVP when the diagnosis of multicystic kidney is suggested by ultrasound. Conservative surgery may then be achieved, as in three of the four cases.