Autoimmune pancreatitis: Pathological, clinical, and immunological features

Introduction: In recent years a type of chronic pancreatitis has been described that is clearly distinct from alcoholic chronic pancreatitis. It is characterized by its special pathology, immunologic features, clinical presentation, and steroid responsiveness. Because of its histologic hallmarks, i.e., ductal and periductal infiltration by lymphocytes, plasma cells, and granulocytes, it has been called duct-destructive chronic pancreatitis. The frequent association of this type of pancreatitis with other autoimmune diseases such as Sjögren's disease and a number of other immune phenomena has led to the concept that it is an autoimmune disease. Hence, the term autoimmune pancreatitis has been introduced and will be used in this review. Aims: This review focuses on the pathology and related clinical and immunologic features of this new type of pancreatitis. Conclusions: As the ability to diagnose autoimmune pancreatitis on the basis of clinical, imaging, and laboratory findings improves, it seems likely that fewer patients with this diagnosis will undergo resection. Thus, there is a need to accumulate and study additional retrospective series of patients undergoing resection because of mass-forming chronic pancreatitis.