Choledochoduodenal fistula in the setting of Crohn's disease.

Of all the spontaneous fistulas that occur between the extrahepatic biliary system and the intestine, a choledochoduodenal fistula is rarely seen. When it does occur, it is most often secondary to a perforated duodenal ulcer, choledocholithiasis, or cholelithiasis. It may also be seen following complications related to iatrogenic injury or tuberculosis. Generally, choledochoduodenal fistulas are asymptomatic, but may present with vague abdominal pain, fever, and other symptoms related to cholangitis. As a result, they can be difficult to diagnose clinically before imaging is obtained. We present a case of a 74 year old, asymptomatic, female with a past medical history significant for Crohn's disease who was found to have a choledochoduodenal fistula demonstrated on MRCP, possibly secondary to her underlying inflammatory bowel disease.