Summary: Autoimmune pancreatitis (AIP) is a special type of chronic pancreatitis mediated by autoimmunity. The classic manifestation of AIP is diffuse pancreatic enlargement, some of which are characterized by focal enlargement. Clinically, it is divided into diffuse AIP (DAIP) and focal AIP (FAIP) according to morphology. FAIP can be clinically manifested as obstructive jaundice, peripancreatic lymphadeno...