ERCP features in 27 patients with autoimmune pancreatitis

Background: Autoimmune pancreatitis has been proposed as a new clinical entity. However, the ERCP features of this entity have not been well described. Methods: Clinical and radiographic features in 27 patients with a diagnosis of autoimmune pancreatitis were evaluated. Results: All 27 patients were at first suspected to have pancreatic cancer. The patients were predominantly elderly men and presented with jaundice or mild symptoms and pancreatic enlargement, but no attack of acute pancreatitis. A cholestatic biochemical profile and serum IgG elevation were usually present. A diffusely or segmentally irregular and narrow main pancreatic duct and a positive response to corticosteroid therapy were characteristic. During observation without treatment, serial pancreatography in 2 patients demonstrated progression of diffuse, irregular narrowing of the main pancreatic duct over periods, respectively, of 2 and 6 months. Both the irregular narrowing of the main pancreatic duct and distal bile duct strictures improved in various degrees in response to corticosteroid therapy. Conclusions: Segmental or diffuse irregular narrowing of the main pancreatic duct are ERCP features of autoimmune pancreatitis.