Bouveret syndrome preceding classical gallstone ileus: a rare presentation of a cholecystoduodenal fistula.

Bouveret syndrome is the rarest variant of gallstone ileus characterized by the passage and impaction of a gallstone through a bilioenteric fistula leading to gastric outlet obstruction. The documented movement of an impacted gallstone in Bouveret syndrome through the gastrointestinal tract has not been previously discussed in the literature. A 64-year-old man presented with acute on chronic epigastric pain, fevers, and vomiting. Abdominal computed tomography established a diagnosis of Bouveret syndrome. A trial of endoscopic gallstone extraction was unsuccessful. Laparoscopic gastrotomy and stone removal were later attempted, however, intraoperatively it was noted that the stone had migrated and was now impacted in the jejunum causing a small bowel obstruction. The clinical picture was now that of gallstone ileus. Laparoscopic enterolithotomy was performed successfully. This article discusses the radiological, endoscopic, and intraoperative findings in this rare case of Bouveret syndrome that had evolved into classical gallstone ileus following stone migration.