Bilioenteric Fistula: A Rare Complication of Biliary Disease. A Case Report

Bilioenteric fistulas are a rare complication of chronic gallstone disease and are characterized by the formation of an abnormal communication between the biliary tract and the gastrointestinal tract. Persistent inflammation, adhesion formation, and progressive erosion caused by gallstones may promote the development of a fistulous tract and allow gallstones to migrate into the intestinal lumen. When a large gallstone becomes impacted and causes mechanical intestinal obstruction, the condition is known as gallstone ileus. We present the case of a 68-year-old woman with a long-standing history of cholelithiasis who presented with colicky abdominal pain, nausea, vomiting, abdominal distension, and decreased bowel movements and passage of flatus. Abdominal computed tomography revealed dilated small-bowel loops, pneumobilia, and an ectopic gallstone impacted in the distal ileum, findings consistent with Rigler's triad. Based on the diagnosis of gallstone ileus, surgical treatment was indicated. Intraoperative exploration revealed a gallstone impacted in the distal ileum, which was removed through an enterotomy, as well as an intense inflammatory process in the right upper quadrant and an abnormal communication between the gallbladder and the duodenum, consistent with a cholecystoduodenal fistula. The intestinal obstruction was relieved, and the underlying biliary disease was managed according to the intraoperative findings. The patient had a favorable postoperative course, with restoration of bowel function and adequate tolerance of oral intake. Bilioenteric fistula complicated by gallstone ileus should be considered in the differential diagnosis of patients presenting with intestinal obstruction, particularly in those with a history of biliary disease. Computed tomography plays a fundamental role in establishing the diagnosis and determining the level of obstruction, while treatment should be individualized according to the patient's clinical condition and intraoperative findings.