Perinatal Magnetic Resonance Imaging Demonstration of Duplication of the Right Renal Collecting System with Ipsilateral Hydronephrosis and Hydroureter, and Contralateral Renal Hypoplasia

摘要

A 36-year-old, gravida 2, para 1, woman was referred at 27 weeks of gestation because of multiple renal cysts on the right side and hypoplasia of the kidney on the left side in the fetus. The parents were non-consanguineous, and there was no family history of polycystic kidneys and renal abnormalities. The patient had undergone amniocentesis which revealed a karyotype of 46,XX. Detailed ultrasound showed a normal amount of amniotic fluid, a singleton fetus with fetal biometry consistent with the gestational age, a duplex right kidney with hydronephrosis and a right megaureter (Fig. 1). The left renal system was hypoplastic. Prenatal magnetic resonance imaging (MRI) showed a right-sided duplex collecting system with a megaureter and hydronephrosis arising from the upper pole moiety and an inferiorly compressed lower pole moiety (Figs. 2 and 3). At 38 weeks of gestation, the woman delivered a female baby weighing 3048 g with Apgar scores of 9 and 10 at 1 minute and 5 minutes, respectively. The postnatal MRI findings were consistent with the prenatal diagnosis (Figs. 4 and 5). The baby underwent an exploratory laparotomy, which confirmed a duplex right kidney and ureter with hydronephrosis and hydroureter arising from the upper pole moiety. Ureteroplasty and reimplantation of the ureter were successfully performed. The child was doing well at the age of 4 months.