Megacystis-microcolon-intestinal hypoperistalsis syndrome: additional clinical, radiologic, surgical, and histopathologic aspects.

Four newborn infants with megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) were identified at Children's Hospital of Pittsburgh. These cases provide additional insight into the syndrome and broaden its spectrum. This report includes MMIHS in an infant boy, one long-term survivor, an apparently related complication of neonatal obstructive volvulus, evidence of small intestinal hypoperistalsis, and histopathologic findings as follows: (1) apparently increased numbers of ganglion cells in early biopsies and normal or even decreased numbers of ganglion cells in later biopsies probably due to bowel dilatation; and (2) in two of three infants at autopsy, there were many nerve trunks (a neuromalike layer in one), and there was elastosis of the urinary bladder.