1. Asymptomatic Cholecystocolonic And Cholecystoduodenal Fistulae In The Same Patient - A Unique Presentation
Saurabh Chandan, MD1; Alexander T. Hewlett, DO2; Grant F. Hutchins, MD2
1. Department of Internal Medicine, University of Nebraska Medical Center (Omaha, NE)
2. Department of Gastroenterology & Hepatology, University of Nebraska Medical Center (Omaha, NE)
Background
Figure 1 (a & b)
Figures 2 & 3
Incidental findings of cholecystocolonic fistulae (CCF) are rarely reported and a review of 160 articles, published between 1950 and 2006 by Costi et al, revealed only 231 such cases.
In patients with repeated episodes of cholecystitis associated with CBD stones1 and absence of pathognomic symptoms like chronic watery diarrhea2, malabsorption of fat-soluble vitamins, especially Vitamin D3 and pneumobilia, suspicion for a CCF must be considered4. 
We present a case of an asymptomatic 67 year old female who was found to have cholecystocolonic and cholecystoduodenal fistulae during a routine colonoscopy.
Case Report
 A 67 year Caucasian female with history of prediabetes and hypertension presented to our facility for a routine surveillance colonoscopy.
During her colonoscopy, a small fistula was found in the transverse colon (figure 1 a&b). This was an incidental finding as the patient did not have any concerning symptoms such as diarrhea or weight loss.
She underwent a lower gastrointestinal series which confirmed the presence of a fistulous tract connecting the hepatic flexure of the colon to a contracted gallbladder with subsequent filling of the biliary tree.
Additionally, a second smaller fistula was visualized which extended from the larger fistula near the hepatic flexure of the colon to the duodenum (figure 3).
An MRCP (figure 2) following this showed an open mouth communication from the gallbladder fundus to the transverse colon and posterior to this communication, there was an additional fistulous tract extending from the second portion of the duodenum to the gallbladder.
Biopsies of the fistula revealed villous blunting with pseudopyloric metaplasia, increased lamina propria inflammation and mild active inflammation negative for granulomas and dysplasia.
Following colo-cystic and coloduodenal fistula take down surgery, she was discharged home and had an uneventful recovery.
Discussion
Internal biliary enteric fistulas (IBFs) are a rare collection of biliary tract pathologies which have previously only been sparsely reported in literature. They have a % detection rate during biliary tract operations. 
A classic triad of pneumobilia, chronic bile acid induced diarrhea and malabsorption of fat-soluble vitamins like Vitamin D often provides high clinical suspicion of these fistulas which then need confirmation with endoscopic evaluation.
However, asymptomatic IBFs are rare and their occurrence warrants reporting.
References
Indar AA, Beckingham IJ. Acute Cholecystitis. BMK 2002; 325:
Inal M, Oguz M, Aksungur E, Soyupak S: Biliary-enteric fisulas: report of five cases and review of literature. Eur Radio 1999; 9L
Benage D, O’Connor KW. Cholecystocolonic fistula: malabsorptive consequences of lost bile acids. J Clin Gastroenterol 1990; 12:
Antonacci N, Taffurelli G, Casadei R, Ricci C; Asymptomatic Cholecystocolonic Fistula: A diagnostic and Therapeutic Dilemma