| umls-concept:C0019569 | skos:definition | MSH: Congenital MEGACOLON resulting from the absence of ganglion cells (aganglionosis) in a distal segment of the LARGE INTESTINE. The aganglionic segment is permanently contracted thus causing dilatation proximal to it. In most cases, the aganglionic segment is within the RECTUM and SIGMOID COLON.,CSP: abnormally large or dilated colon due to congenital absence of myenteric ganglion cells in a distal segment of the large bowel; resultant loss of motor function in this segment causes massive hypertrophic dilatation of the normal proximal colon; condition appears soon after birth; called also Hirschsprung's disease, aganglionic megacolon and pelvirectal achalasia.,NCI: A congenital disorder characterized by the absence of myenteric ganglion cells in the distal colon. It results in a functional stenosis of the distal colon and a massive distention of the proximal colon. | lld:umls |
