Neuronal intestinal dysplasia is characterized by structural changes consisting of hyperplasia of the myenteric plexus, an increase of the acetyl cholinesterase activity and the formation of giant ganglia. The condition gives rise to signs and symptoms similar to Hirschsprung's disease. Neuronal intestinal dysplasia can occur as a clinical entity itself in a localized or disseminated form. It may also accompany Hirschsprung's disease either as a localized defect or as a disseminated disorder of the entire intestinal tract. In localized forms, resection of the entire diseased segment is curative. Disseminated forms often have a fetal outcome despite ileostomy and colectomy. It is conceivable that differences in the severity of symptoms depend upon the development or absence of sympathetic innervation.