A Rare Cause of Gastric Outlet Obstruction: A Case Report of Bouveret Syndrome.

Bouveret syndrome (BS) is a rare phenomenon of gallstone ileus causing gastric outlet obstruction that can present significant challenges in management, given its lack of formal treatment guidelines and endoscopic difficulty. We present a case of an 84-year-old woman with vomiting and abdominal pain who was found to have a large gallstone in the duodenum due to a cholecystoduodenal fistula, as well as findings consistent with acute cholecystitis. She was treated with antibiotics, and gastroenterology and general surgery were consulted. Endoscopy was performed due to high suspicion for BS, revealing a 4-5 cm gallstone impacted in the first portion of the duodenum. Stone removal was extremely challenging, but ultimately 75% of the stone was fragmented using holmium laser lithotripsy, with the remaining fragments passing distally. The patient tolerated the procedure well; antibiotics were continued; and surgery was initially avoided. The patient presented three weeks later with abdominal pain and a small bowel obstruction (SBO) secondary to the remaining stone fragment. General surgery was consulted, and she underwent a laparoscopic small bowel resection with stone retrieval. This case highlights the complex management of BS, which requires advanced endoscopic techniques. However, it is often treated with surgery for definitive management if endoscopy is unsuccessful. Early diagnosis and multidisciplinary collaboration between medicine, gastroenterology, and general surgery are critical to prevent complications in this rare form of gallstone ileus.