Hirschsprung's disease: diagnosis and management.

Hirschsprung's disease (congenital megacolon) is caused by the failed migration of colonic ganglion cells during gestation. Varying lengths of the distal colon are unable to relax, causing functional colonic obstruction. Hirschsprung's disease most commonly involves the rectosigmoid region of the colon but can affect the entire colon and, rarely, the small intestine. The disease usually presents in infancy, although some patients present with persistent, severe constipation later in life. Symptoms in infants include difficult bowel movements, poor feeding, poor weight gain, and progressive abdominal distention. Early diagnosis is important to prevent complications (e.g., enterocolitis, colonic rupture). A rectal suction biopsy can detect hypertrophic nerve trunks and the absence of ganglion cells in the colonic submucosa, confirming the diagnosis. Up to one third of patients develop Hirschsprung's-associated enterocolitis, a significant cause of mortality. Patients should be monitored closely for enterocolitis for years after surgical treatment of Hirschsprung's disease. With proper treatment, most patients will not have long-term adverse effects and can live normally.