[Gastrointestinal bleeding and delirium, challenges in the diagnosis of gallstone ileus: A case report and review of literature].

Background: Gallstone ileus is a non-strangulated mechanical obstruction of the small bowel or colon as a result of the passage of gallstones through a biliary enteric fistula. It is a rare complication of cholelithiasis, affects patients over 65 years, and the disease occurs predominantly in females. Preoperative diagnosis is difficult due to the lack of specific signs and symptoms in elderly patients with multiple comorbidities.