Hepatobiliary and pancreatic: Choledochopancreatic fistula complicating acute pancreatitis

Abstract

A 39-year-old man was admitted to hospital with a pseudocyst that developed after acute necrotizing pancreatitis. A computed tomography (CT) scan demonstrated a pseudocyst in the body of the pancreas with some compression of the common bile duct. At surgery, the cyst was drained with a drain-tube. After 2 months, there was continued drainage of approximately 100 mL of bile-stained fluid each day. Water-soluble contrast was introduced through the percutaneous drain and showed a residual cavity (long arrow) and filling of the main pancreatic duct and biliary system (Fig. 1). The bile duct was mildly dilated and there was a long common channel at the pancreatobiliary junction (short arrow). A CT scan obtained during the introduction of water-soluble contrast showed a stricture in the main pancreatic duct in the body of the pancreas, mild dilatation of the duct in the tail of the pancreas and a possible additional stricture close to the ampulla of Vater. Endoscopic retrograde cholangiopancreatography with the catheter in the main pancreatic duct (Fig. 2) confirmed the presence of a stricture in the body of the pancreas (short arrow) as well as filling of the lower bile duct (long arrow). The diagnosis was that of a fistula between the main pancreatic duct and biliary system. The fistula was treated by the endoscopic placement of a pancreatic stent. Pancreatic fistulas are uncommon complications of acute pancreatitis. The typical fistula is caused by the spontaneous rupture of a pancreatic pseudocyst into the peritoneal cavity with the development of pancreatic ascites. The latter disorder can also occur after pancreatic necrosis without the development of a pseudocyst. Rarely, spontaneous fistulas can communicate with the pleural cavity (pancreatic pleural effusion) or with the gastrointestinal tract, usually because of rupture of pseudocysts. In the case described above, the pseudocyst communicated with both the main pancreatic duct and the bile duct. Furthermore, injection of radiological contrast into the main pancreatic duct resulted in filling of the bile duct. Although stenting of the main pancreatic duct is being increasingly used in patients with pancreatic fistulas, another option in the above case would be stenting of both ducts.