Cholecystoduodenal fistula: a rare cause of intestinal obstruction, an extraordinary cause of hematemesis.

<title>Abstract</title> Cholecystoduodenal fistula is a rare complication of cholelithiasis. Symptoms are usually nonspecific, rarely presenting as biliary ileus and exceptionally as upper gastrointestinal bleeding. We present a case of a 77-year-old patient with cholecystoduodenal fistula who presented with hematemesis diagnosed by endoscopy and computed tomography and later complicated by a biliary ileus in the form of Bouveret's syndrome. Finally, surgical management by enterolithotomy and open cholecystectomy was chosen; endoscopic hemostasis could not be achieved, but surgical treatment was successful. Hemorrhage and biliary ileus associated with cholecystoduodenal fistulas usually require surgery because it is unlikely that treatment of the hemorrhage or removal of the lithiasis can be accomplished by conservative or endoscopic treatment. Cholecystoduodenal fistula should be considered as a differential diagnosis when a patient with a history of biliary disease presents with gastrointestinal bleeding.