Endoscopic management of gallstone large bowel obstruction at a sigmoid diverticular stricture secondary to cholecystoduodenal fistula.

Gallstone ileus is a rare cause of mechanical bowel obstruction, typically involving the small intestine. Large bowel obstruction (LBO) due to gallstone impaction is exceedingly uncommon, particularly at a sigmoid stricture. We present the case of a 76-year-old male with significant cardiac comorbidities who was managed non-operatively for acute cholecystitis complicated by cholecystoduodenal fistula. He subsequently re-presented with LBO from an impacted gallstone at a sigmoid diverticular stricture. Multidisciplinary endoscopic intervention using mechanical lithotripsy avoided surgical resection. This case highlights the potential for nonoperative management of gallstone LBO in select patients and emphasizes the utility of advanced endoscopic techniques in the setting of challenging anatomy. It also contributes to the limited but growing body of literature describing colonic gallstone ileus, particularly in the context of diverticular disease.