Chronic Gallstone Ileus Presenting as Acute Small Bowel Obstruction: A Case Study

Introduction

Small bowel obstruction secondary to a foreign body that necessitates retrieval is an uncommon occurrence. Gallstone ileus is a rare cause of intestinal obstruction, accounting for less than 1% of cases, and occurs most frequently in elderly women [1]. Gallstones can be located throughout the gastrointestinal tract, from the stomach to the colon. The most frequent mechanism of gallstone ileus is through a gallbladder-duodenal fistula from the posterior wall of the body of the gallbladder, and the most frequent area of obstruction is the ileocecal valve [2]. Additional routes may include the common bile duct, transverse colon, and stomach. Although pathognomonic, Rigler’s classic triad and radiographic features are not always observed [2,3].

Case Report

A 71-year-old man presented to the Emergency Department with a 3-day history of worsening colicky lower abdominal pain, constipation, fever, and nausea. His last reported bowel movement was 3 days prior, and he ceased passing flatus the day before presentation. Abdominal exam revealed bilateral lower abdominal tenderness and mild distension, with no rebound or guarding. Abdominal computed tomography (CT) showed a radiopaque, triangular-shaped foreign body located in the distal small bowel, with proximal bowel dilation and fecalization (Figure 1C). Review of prior imaging from 2 and 4 years prior showed the same foreign body located more proximally within the jejunum, with no obstructive symptoms at that time (Figure 1A, 1B). The patient stated he had previous knowledge of the foreign body and denied consuming any foreign objects. At both times of prior imaging, the foreign body was found incidentally while the patient was undergoing evaluation for nephrolithiasis. During previous encounters, he was asymptomatic with no symptoms of abdominal pain, biliary colic, or bowel dysfunction from the foreign body, and there were no further investigations, referrals, or follow-up. He had no history of slow transit or self-resolving incomplete small bowel obstruction episodes. His past surgical history was significant for an open appendectomy and bilateral open inguinal hernia repairs. Review of current and previous CT scans failed to demonstrate signs of cholelithiasis, cholecystitis, or air in the biliary system. No other imaging was performed, as he had no symptoms of biliary colic at the previous and current evaluations.

The patient’s vitals were stable, with a white blood cell count of 11.47×109/L and no lactic acidosis. He was started on intravenous fluids, with no oral intake, and had a nasogastric tube placed prior to surgery. An exploratory laparoscopy was performed, in which the distal ileum was identified, running back to the transition site where the obstruction was located. No strictures or adhesions were seen to explain the location of the obstruction. A flat grasper was placed at the distal bowel to prevent movement of the foreign body. An infraumbilical midline incision was made and a wound protector placed. The small bowel was delivered up from the abdomen and a longitudinal enterotomy was made. A 4-cm foreign body was removed and the enterotomy was closed transversely. The bowel was replaced in the abdomen and the incision sites were closed.

On visual inspection, the foreign body removed was ovoid, solid, and hard, measuring 4×4 cm (Figure 2). Pathology following gross dissection of encasing fecal material revealed a 3×3×0.6 cm smooth brown-black gallstone. A later cholecystectomy and/or repair of biliary-enteric fistula were not indicated as there was no evidence of cholecystitis, cholelithiasis, or air in the biliary system. Postoperatively, the patient improved clinically and did well with advancement of diet. He was discharged home with no complications on postoperative day 4.

Discussion

Gallstone ileus is an uncommon cause of intestinal obstruction. The typical triad observed is a small bowel obstruction, air in the biliary tract, and an obstructing gallstone. Rigler described 4 classic radiographic findings: partial or incomplete bowel obstruction, air or contrast in biliary tract, visualization of stone in intestine, and change in position of a previous stone [3]. Our case demonstrated 3 of 4 radiographic findings: partial or incomplete bowel obstruction, visualization of stone in intestine, and change in position of a previous stone. Biliary fistulas have a tendency to obliterate on their own; therefore, absence of pneumobilia does not rule out gallstone ileus [3].

Conclusions

Gallstone ileus is a rare cause of intestinal obstructions. There are 4 classic radiographic findings: partial or incomplete bowel obstruction, air or contrast in biliary tract, visualization of stone in intestine, and change in position of a previous stone. A gallstone ileus should strongly be considered when a foreign body is present in association with the above findings.