S1827 Sigmoid Gallstone Ileus with Obstruction Treated with Endoscopic Intervention

INTRODUCTION: A gallstone Ileus is a rare form of mechanical intestinal obstruction caused by gallstone impaction within the gastrointestinal tract that occurs following the formation of a cholecystoenteric fistula. Cholecystoenteric fistula most commonly involve the duodenum, however, the colon is also a potential site of involvement. Cholecystocolonic fistulas are exceedingly rare and present with colonic obstruction. We report of a case of sigmoid gallstone ileus managed with endoscopic intervention. CASE DESCRIPTION/METHODS: An 84-year-old male with a history of diverticulosis presented to the ED with a complaint of abdominal pain and obstipation for 5 days. The patient denied any symptoms of GI bleeding, emesis or fever. He had a screening colonoscopy 10 years prior, which was unremarkable. Initial examination revealed abdominal distension and diffuse abdominal tenderness. CT scan of the abdomen and pelvis showed a 3.5 × 3.0 cm soft tissue lesion with colonic wall thickening in the proximal sigmoid colon, and upstream colonic distension. Pneumobilia was seen in the left hepatic lobe. A colonoscopy was performed which revealed a 4 cm impacted gallstone in the sigmoid colon. Because the gallstone was impacted, hot snare cautery was applied to break up the gallstone. Fragments were then removed with a Roth net. A HIDA scan was negative for a cholecystocolonic fistula, and MRCP revealed a contracted gallbladder containing a 2.9 cm × 2.5 cm gallstone with no identifiable fistula. However, given the findings of pneumobilia and bowel obstruction on CT along with the endoscopic findings of an impacted gallstone in the sigmoid colon, it was presumed that the fistulization had occurred between the gallbladder and adjacent hepatic flexure of the colon. After removal of the impacted gallstone, the patient did well with complete resolution of his symptoms. DISCUSSION: We describe a case of successful treatment of sigmoid gallstone ileus by endoscopic removal of an impacted gallstone using hot snare cautery. Sigmoid gallstone ileus is a rare cause of colonic obstruction that primarily occurs in the elderly and only accounts for 4% of all cases of gallstone ileus. Gallstones larger than 2.5 cm can cause obstruction of the colon and can occur at a site of previous pathology. The diagnosis requires a high degree of clinical suspicion and management should focus on early diagnostic imaging, followed by either endoscopy or surgical intervention to remove the impacted gallstone and thereby relieve the obstruction.Figure 1.: CT Abdomen and Pelvis showing 3.5 × 3.0 cm soft tissue lesion with mild wall thickening in the proximal sigmoid colon, and upstream colonic distention.Figure 2A.: Large 4cm gallstone seen in the Sigmoid colon, just proximal to an area of relative luminal narrowing.Figure 3.: Gallstone fragments after hot snare cautery was utilized to break up the stone.