[A case of autoimmune pancreatitis combined with extensive involvement of biliary tract].

Autoimmune pancreatitis is a distinct disease characterized by the presence of autoantibodies and hypergammaglobulinemia, inflammation of the pancreatic parenchyma, and irregular stricture of the pancreatic duct. The involvement of distal common bile duct is frequently observed, but intrahepatic bile duct involvement is very rare, which seem to have similar feature to primary sclerosing cholangitis. We report a case of the patient with autoimmune pancreatitis combined with extensive involvement of extrahepatic and intrahepatic bile duct, which had a favorable response to steroid therapy.