Gallstone Ileus Caused by Cholecystocolonic Fistula and Gallstone Impaction in the Sigmoid Colon: Review of the Literature and Novel Surgical Treatment with Trephine Loop Colostomy.

Gallstone ileus is an uncommon cause of intestinal obstruction and occurs following the formation of a cholecystoenteric fistula, permitting passage of gallstones into the gastrointestinal tract. Impaction of a gallstone in the sigmoid colon is rare and is usually at sites of previous colonic disease. Definitive management can be challenging due to the advanced age and co-morbidity usually seen in this group of patients.