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. We describe a patient successfully managed with on-table endoscopy and, under local anaesthetic, the formation of a left iliac fossa trephine loop colostomy, permitting an enterolithotomy to deliver the stone whilst accommodating for severe pre-existing distal sigmoid diverticular disease. A review of the literature identified various endoscopic and surgical treatments that, depending on local expertise and patient characteristics, can be considered on a case-by-case basis. We advocate the management described in this case for patients presenting with large bowel obstruction due to gallstone ileus, with a background of diverticular disease and who are not fit for general anaesthetic or formal bowel resection, as an alternative to medical palliation alone.