A 3,692-g full-term infant girl was admitted to the hospital with abdominal distention and bilious vomiting. Prenatal maternal sonography for evaluation of an abnormally large uterus had showed polyhydramnios; fetal sonography had revealed a cystic abdominal mass. Physical examination showed a tachypneic infant with a small omphalocele and massive abdominal distention. Combined chest and abdominal roentgenograms were obtained, and they showed a distended, relatively gasless abdomen. Abdominal sonography (Fig 1), cystography (Fig 2), and a contrast-medium enema (Fig 3) preceded exploratory laparotomy.
Denouement and Discussion
Megacystis-Microcolon-Intestinal Hypoperistalsis Syndrome
Abdominal sonography indicated that the cystic abdominal mass was a huge bladder; cystography confirmed megacystis without evidence of vesicoureteral reflux or bladder outlet obstruction. Contrast-medium enema showed a displaced microcolon that did not empty spontaneously. Initial laparotomy for repair of the small omphalocele showed a nonobstructed thick-walled bladder, nonurinary ascites, and a foreshortened distal small bowel and microcolon without intestinal atresia. Due to postoperative bilious vomiting, contrast-medium examination