Controversial Issues of Recent Diagnostic Criteria of Type 1 Autoimmune Pancreatitis
The diagnosis of autoimmune pancreatitis (AIP) is clinically challenging because it is a rare disease, which closely mimics more common pancreaticobiliary malignancies in its presentation such as obstructive jaundice and pancreatic mass. The price of misdiagnosis is high because AIP diagnosed as pancreatic cancer can lead to unnecessary surgery for the benign disease, and cancer diagnosed as AIP can delay potentially curative surgery. There is no single ideal diagnostic test for AIP; hence one has to use a set of diagnostic criteria to distinguish it from other diseases. International consensus diagnostic criteria (ICDC) and algorithm for AIP have been proposed by a consensus of expert opinion in 2011. The concept of the Japan pancreas society (JPS) 2011 criteria took basic concepts of both the Japanese previous criteria and type 1 in the ICDC as much as possible. However, the ICDC are very complex to remember and definition of level 1 and 2 are not evidence based in some criteria. The revised JPS criteria are simpler than ICDC but further evaluation is necessary in other than Japan. So, further research is required to establish easy, ideal and practical diagnostic criteria.