ABSTRACT
Megacolon is an uncommon condition in which the bowel is persistently of increased diameter and it is always associated with long-standing constipation. Two main groups are recognized according to whether or not ganglia are present in the intermuscular plane of the rectal wall. Their complete absence, even along a short segment of rectum, denotes Hirschspurung's disease. If ganglia are present, the dilated bowel may be secondary to some predisposing factor such as a stricture, a congenital anorectal abnormality, a cauda equina lesion etc. In other instances, however, there may be no apparent organic reason as to why the bowel should be so dilated. This latter condition is termed "idiopathic megacolon". We report the case of one female patient with idiopathic megacolon. During medical treatment, she was complicated with a sigmoid volvulus, we performed subtotal colectomy and cecorectal anastomosis and she improved without any complication.