Congenital megacystis: a case report.

Congenital megacystis without other anomalies is extremely rare. A female newborn, delivered by cesarean section at the gestational age of 36 weeks, was seen. Her prenatal sonogram at 28 weeks' gestation had demonstrated a large cystic lesion in the abdomen. Abdominal distention with a palpable mass, difficult feeding and vomiting were noted after delivery. Abdominal computed tomography scan revealed a large cyst in the middle abdomen without any other anomaly. Exploratory laparotomy was performed on the fourth day of life, and showed a large bladder with normal trigon and normal ureteral insertion. There was no abnormality of other abdominal organs. Reductive cystoplasty was performed and the post-operative course was uneventful. The infant was doing well after an eight-month follow-up. Although congenital megacystis is rare, it should be considered in the differential diagnosis of any intraabdominal cystic lesion demonstrated in a prenatal sonogram. The etiology is obscure, and the benefit of reductive cystoplasty needs more cases to be confirmed.