Diagnosis of Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP) is a peculiar form of pancreatitis that includes two distinct forms of disease, type 1 and type 2. These two entities clearly differ in terms of pathological and epidemiological features but both share a suspected autoimmune etiology and a full response to steroids. The clinical onset of AIP is most frequently characterized by jaundice, more rarely by abdominal pain, acute pancreatitis, weight loss, or signs of exocrine and/or endocrine insufficiency. The most significant step in the clinical approach to the disease is the diagnosis, and the differential diagnosis with pancreatic cancer in the focal form. The current diagnostic strategy is based on the International Consensus Diagnostic Criteria published in 2011, which considers five cardinal criteria for the diagnosis of AIP: imaging of the pancreatic parenchyma and ducts, serology (serum IgG4), other organ involvement, histology, and response to steroid therapy.