P0206 - Colonic Gallstone Obstruction

Abdoulaziz Toure, MD
Arnot Ogden Medical Center, Elmira, NY

Introduction: Gallstone ileus is a rare complication of cholelithiasis and accounts for < 4% of all mechanical small bowel obstruction and up to 25% in the elderly. Involvement of the colon is extremely rare and occurs due to the migration of a stone through a cholecystocolic fistula. Entero-lithotomy has been recognized as the mainstay therapeutic goal however some cases can undergo endoscopic detection and extraction, especially in a stable patient. Given its rarity, no specific treatment guidelines or algorithms for large colon stone obstructions have been proposed.

Case Description/Methods: A 79-yo female with PMH of HTN, HLD presented with a month of dull crampy lower left abdominal pain with associated nausea, emesis, constipation, fatigue and10-lbs weight loss. No relief with laxatives and enemas, and her last BM was a month ago. She is a nonsmoker with a family history of cervical cancer in her mother and no previous records of colonoscopy.
On exam, she was tender in the LLQ with mild distention; absent peritonitis, and normoactive bowel sounds. VS were stable and normal; WBC was 10.3 x 10³/uL; Hgb and Hct was 12.7g/dL and 38%; K+ was 3.3 mmol/L. A stool occult was negative; the rest of the lab studies were unremarkable. Abdominal x-ray and CT showed a 2.5 cm calculi at the junction of the descending and sigmoid colon; and a stone at the neck of the gallbladder. Following resuscitation, a flexible sigmoidoscopy with lithotripsy was performed and the impacted stone retrieved. A 6-week follow-up colonoscopy revealed diverticulosis without stricture or inflammation and a fistulous site in the transverse colon.

Discussion: Gallstone ileus is a rare complication usually precipitated by acute cholecystitis or cholelithiasis. With the inflammation of the gallbladder, an offending calculus may erode into an adjacent GI tract through a fistulous tract. The stone can either pass spontaneously or can impact the GI tract if > 2.5 cm in size. The most commonly involved sites are the terminal ileum and the ileocecal valve. The colon can be involved due to luminal narrowing or strictures caused by diverticular disease or neoplasms therefore, a CT scan remains a gold standard diagnostic tool. While entero-lithotomy is usually performed, detection and retrieval can also be attained via endoscopy with or without lithotripsy depending on the location of the stone in a stable patient. This can be an effective intervention without the need for acute surgery especially in the elderly or high surgical risk patients.


Figure: Image 1. - A plain abdominal film revealing a normal bowel gas pattern in the colon with evidence of an obstructing body at the distal descending colon.
Image 2. - CT scan revealing a cholecystocolic fistula at the hepatic flexure with a 2.5cm impacted gallstone at the distal descending and proximal sigmoid colon. There is also a gallstone at the neck of the gallbladder with intra-luminal air within the gallbladder.
Image 3. - Colonoscopy with Lithotripsy showing an impacted calculus in the descending colon that was crushed and the fragments retrieved.


Disclosures:
Abdoulaziz Toure indicated no relevant financial relationships.


Abdoulaziz Toure, MD. P0206 - Colonic Gallstone Obstruction, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.