An Unusual Sequela of Longstanding Gallstone Disease

Question: The patient is a 71-year-old man with hypertension who presented to his primary care physician with a 6-month history of progressive weight loss, a 5-day history of fevers (up to 103°F), abdominal pain, and jaundice. On examination, he had mild right upper quadrant pain without peritonitis. He was found to have significant leukocytosis (33.6 × 109/L) and was sent to a local emergency room for further evaluation. Additional relevant laboratory values included hemoglobin 11.5 g/dL, international normalized ratio 1.5, creatinine 2.83 mg/dL, total bilirubin 10.9 mg/dL, lipase 13,773 U/L, alkaline phosphatase 677 U/L, aspartate transaminase 61 U/L, and alanine transaminase 78 U/L. A computed tomographic (CT) scan of the abdomen demonstrated a row of calcifications in the bile duct resulting in dilation of the intra- and extra-hepatic biliary tree (Figure A). In the emergency department, he became hypotensive and required norepinephrine to support his blood pressure. He was transferred to our university hospital for further care owing to the concern for ascending cholangitis. He was aggressively resuscitated with intravenous fluids and started on broad-spectrum antibiotics. Endoscopic retrograde cholangiopancreatography (ERCP) was performed and demonstrated purulent material and multiple gallstones in the common bile duct. A sphincterotomy was performed and multiple small stones were evacuated. Owing to ongoing hemodynamic instability during the procedure, a large stone was left in place (Figure B). Stents were placed in the common bile and main pancreatic ducts to ensure biliopancreatic drainage. All of his clinical and laboratory parameters improved after the procedure. A repeated ERCP (with choledocoscopy) performed 1 month later reconfirmed the presence of a large ovoid filling defect, which was concerning for a large polyp. Cold forcep biopsies were taken, and the final pathology revealed plant material and biliary mucosa, but no tumor. After another month, a third ERCP was performed to evaluate the biliary tree in anticipation of operative intervention, but no filling defect was observed (Figure C). With no remaining evidence of biliary obstruction on preoperative imaging, a laparoscopic cholecystectomy was planned. On entry into the abdomen, a large amount of inflammation was observed in the gallbladder fossa. The procedure was converted to open, and further dissection revealed that a segment of the transverse colon was inseparable from the underside of the gallbladder (Figure D). What is the most likely diagnosis, and how should it be managed? Look on page 39 for the answer and see the Gastroenterology website (www.gastrojournal.org) for more information on submitting to Gastro Curbside Consult. Cholecystoenteric fistulas are rare entities that typically result from long-standing gallstone disease.1Huang S.F. Han Y.H. Chen J. Zhang J. Huang H. Surgical management of cholecystoenteric fistula in patients with and without gallstone ileus: an experience of 29 cases.Front Surg. 2022; 9950292Google Scholar Importantly, these fistulas are often not diagnosed on preoperative imaging and are found only on surgical exploration.2Savvidou S. Goulis J. Gantzarou A. Ilonidis G. Pneumobilia, chronic diarrhea, vitamin K malabsorption: a pathognomonic triad for cholecystocolonic fistulas.World J Gastroenterol. 2009; 15: 4077-4082Crossref PubMed Scopus (29) Google Scholar When there is marked inflammation in the right upper quadrant near the gallbladder fossa and dense adhesions, a broad list of differential diagnoses must be considered, including gallbladder perforation secondary to infection, a malignant process, or a fistula from the gallbladder to the surrounding enteric structures. For definitive treatment, a tangential wedge resection of the colon wall was performed, which clearly demonstrated the cholecystocolonic fistula (Figure E). The colon was closed primarily and the cholecystectomy was completed in a routine fashion. Cholecystocolonic fistulas are the second most common cholecystoenteric fistula (after cholecystoduodenal fistulas) and occur in approximately 0.06% to 0.14% of patients undergoing cholecystectomy.3Costi R. Randone B. Violi V. et al.Cholecystocolonic fistula: facts and myths. A review of the 231 published cases.J Hepatobiliary Pancreat Surg. 2009; 16: 8-18Crossref PubMed Scopus (77) Google Scholar Typically, these cholecystocolonic fistulas occur with a female:male ratio of 2.5:1 and at an average age of 69 years.3Costi R. Randone B. Violi V. et al.Cholecystocolonic fistula: facts and myths. A review of the 231 published cases.J Hepatobiliary Pancreat Surg. 2009; 16: 8-18Crossref PubMed Scopus (77) Google Scholar The initial presenting symptoms can be quite variable. In the acute setting, patients can present with symptoms of cholecystitis, pancreatitis, or cholangitis.2Savvidou S. Goulis J. Gantzarou A. Ilonidis G. Pneumobilia, chronic diarrhea, vitamin K malabsorption: a pathognomonic triad for cholecystocolonic fistulas.World J Gastroenterol. 2009; 15: 4077-4082Crossref PubMed Scopus (29) Google Scholar However, often the most predominant symptom is chronic diarrhea, likely due to multiple factors including excess bile acids in the colon.3Costi R. Randone B. Violi V. et al.Cholecystocolonic fistula: facts and myths. A review of the 231 published cases.J Hepatobiliary Pancreat Surg. 2009; 16: 8-18Crossref PubMed Scopus (77) Google Scholar,4Choi C. Osman K. Hartley C.P. Maselli D.B. Cholecystocolonic fistula as an uncommon cause of diarrhea: a case-report and review of the literature.Clin J Gastroenterol. 2021; 14: 1147-1151Crossref PubMed Scopus (0) Google Scholar In our patient, acute cholangitis rapidly progressed to septic shock, which was quickly treated with biliary decompression, fluid resuscitation, and antibiotic therapy. The large polypoid mass seen in the common bile duct was proven to be plant material from the colonic fistula, which ultimately spontaneously resolved. The final pathology after surgery revealed chronic cholecystitis with cholelithiasis, a cholecystocolonic fistula, and no evidence of malignancy. The patient’s post-operative recovery was uneventful and he was discharged to home within a few days. Although it is uncommon and not often diagnosed before surgery, gastroenterologists and surgeons must be aware of the potential of encountering a biliary-enteric fistula and be prepared to diagnose and treat in the endoscopy suite and the operating room.