Idiopathic megacolon is one of the culprit for chronic constipation and is a rare condition. Megacolon is divided into 3: Acute megacolon in which there is no obvious colonic disease (colonic pseudo obstruction); chronic megacolon which could be congenital, acquired or idiopathic; toxic megacolon, which occurs in association with inflammation of the colon. Until date, the exact prevalence of idiopathic megacolon is unknown. The onset of symptoms either in childhood or adulthood and more common among females. The objective is to report idiopathic megacolon as a rare cause of chronic constipation. We report a 55-year old woman, who presented with 10 days history of no bowel open and abdominal distention. She been having chronic constipation for the past 5 years and dependent on laxatives. Contrasted enhanced computer tomography abdomen revealed grossly dilated descending and sigmoid colon with no obvious pathology. She was took to Operation Theater for exploratory laparotomy in view of grossly distended painful abdomen. Intra-operatively, grossly dilated descending and sigmoid colon with no obvious pathology detected. The others part of colon were normal in calibre. Decision for Hartmann’s procedure was made and the final histopathological examination (HPE) reported as idiopathic megacolon.
