title: Autoimmune pancreatitis can develop into chronic pancreatitis.
abstract: Autoimmune pancreatitis (AIP) has been recognized as a distinct type of pancreatitis that is possibly caused by autoimmune mechanisms. AIP is characterized by high serum IgG4 and IgG4-positive plasma cell infiltration in affected pancreatic tissue. Acute phase AIP responds favorably to corticosteroid therapy and results in the amelioration of clinical findings. However, the long-term prognosis and outcome of AIP remain unclear. We have proposed a working hypothesis that AIP can develop into ordinary chronic pancreatitis resembling alcoholic pancreatitis over a long-term course based on several clinical findings, most notably frequent pancreatic stone formation. In this review article, we describe a series of study results to confirm our hypothesis and clarify that: 1) pancreatic calcification in AIP is closely associated with disease recurrence; 2) advanced stage AIP might have earlier been included in ordinary chronic pancreatitis; 3) approximately 40% of AIP patients experience pancreatic stone formation over a long-term course, for which a primary risk factor is narrowing of both Wirsung's and Santorini's ducts; and 4) nearly 20% of AIP patients progress to confirmed chronic pancreatitis according to the revised Japanese Clinical Diagnostic Criteria, with independent risk factors being pancreatic head swelling and non-narrowing of the pancreatic body duct.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Maruyama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Watanabe
authors.forename: Keita
authors.initials: K
authors.lastname: Kanai
authors.forename: Takaya
authors.initials: T
authors.lastname: Oguchi
authors.forename: Jumpei
authors.initials: J
authors.lastname: Asano
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ito
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Ozaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Muraki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Hamano
authors.forename: Norikazu
authors.initials: N
authors.lastname: Arakura
authors.affiliation: Center for Health, Safety, and Environmental Management, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621, Japan. skawapc@shinshu-u.ac.jp.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Kawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000503:physiopathology*; D002114:Calcinosis; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000503:physiopathology*; D011379:Prognosis; D012008:Recurrence; D012307:Risk Factors