Current Management of Type 1 Autoimmune Pancreatitis: From the Viewpoint of Pancreatic Endocrine and Exocrine Function

Autoimmune Pancreatitis (AIP) is a pancreatic inflammatory disease caused by an autoimmune mechanism. Histologically, two subtypes exist: type 1 characterized by lymphoplasmacytic sclerosing pancreatitis and type 2 characterized by idiopathic duct-centric chronic pancreatitis. Type 1 AIP often involves extra pancreatic lesion, and also known as a pancreatic lesion of systemic “immunoglobulin G4 (IgG4)-related disease”. In addition, pancreatic endocrine dysfunction induced diabetes mellitus and exocrine dysfunction is common complications. While steroid therapy improves the outcome of the disease in some patients including pancreatic endocrine/exocrine function, others do not respond to steroids that results in the eventual progression to pancreatic endocrine/exocrine dysfunction, such as chronic pancreatitis. In the management of type 1 AIP, presence of pancreatic endocrine/exocrine function should always be considered, in addition to the regular steroid therapy