Autoimmune pancreatitis

Abstract

Although the pathogenesis of autoimmune pancreatitis is unclear, recent evidence of clinical aspects are presented: (i) mild abdominal symptoms, usually without acute attacks of pancreatitis; (ii) occasional existence of obstructive jaundice; (iii) increased levels of serum gammaglobulin, IgG or IgG4; (iv) presence of autoantibodies; (v) diffuse enlargement of the pancreas; (vi) irregularly narrowing of the pancreatic duct (sclerosing pancreatitis) with often intra-pancreatic biliary stenosis or coexistence of biliary lesions (sclerosing cholangitis similar to primary sclerosing cholangitis: PSC) on endoscopic retrograde cholangiopancreatographic (ERCP) images; (vii) fibrotic changes with lymphocyte and IgG4-positive plasmacyte infiltration, and obliterative thrombo-phlebitis; (iix) occasional association with other systemic lesions such as sialoadenitis, retroperitoneal fibrosis, interstitial renal tubular disorders, and (ix) effective steroid therapy. In addition to pancreatic and extrapancreatic lesions, diabetes mellitus is occasionally responsive to steroid therapy. Further studies are needed to clarify the pathogenesis.