Hirschsprung's Disease

Hirschsprung's disease (HD) is a disorder of the gut that occurs when all or part of the large intestine has no nerves and therefore cannot function. During normal fetal development, cells from the neural crest migrate into the large intestine (colon) to form a network of nerves called Auerbach's plexus. In Hirschprung's disease, the migration is not complete and part of the colon lacks these nerve bodies that regulate the activity of the colon. The affected segment of the colon cannot relax, which blocks the passage of stool through the colon. In most affected people, the disorder affects the part of the colon that is nearest the anus. In rare cases, the lack of nerve bodies involves more of the colon. In five percent of cases, the entire colon is affected. Hirschsprung's disease is also sometimes called congenital aganglionic megacolon.

Hirschsprung's disease occurs in about one in 5,000 children (U.S. and Japan). It is usually diagnosed in children, and affects boys more often than girls.