Summary of Autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a chronic fibroinflammatory disease characterized by prompt response to steroid therapy. AIP presents as two distinct subtypes.

• AIP-1: AIP-1 belongs to the group of IgG4-related diseases histologically characterized by storiform cellular fibrosis, obliterative phlebitis, and periductal chronic inflammation rich in IgG4-positive plasma cells.
• AIP-2:  AIP-2: also known as idiopathic duct-centric pancreatitis, characterized by Ductal inflammation with intraepithelial neutrophils (so-called, granulocytic epithelial lesion), luminal neutrophilic abscesses, extensive fibrosis, but no apparent storiform or hypercellularity.