title: Is idiopathic chronic pancreatitis an autoimmune disease?
abstract: OBJECTIVE
  The proportion of patients with idiopathic chronic pancreatitis (ICP) that have an autoimmune origin is unknown. Three forms of ICP have been described: pseudotumoral, duct-destructive, and usual chronic pancreatitis. The aim of this study was to identify autoimmune stigmata in the 3 forms.
  
  
  METHODS
  All patients who underwent exploration for ICP were included. The following data were recorded: examination by an internal medicine specialist, autoantibodies and immunoglobulin screening, and pancreatic duct imaging.
  
  
  RESULTS
  Sixty patients were included (pseudotumoral, n = 11; duct-destructive, n = 27; usual, n = 22). There were no significant differences among the 3 types with regard to sex ratio, age, frequency of acute pancreatitis, or obstructive jaundice. Pancreatic calcifications were seen only in the usual form (81%; P = .0001). Autoimmune disease was present in 10 patients: ulcerative colitis in 5 patients, primary sclerosing cholangitis in 2 patients, and Sjögren's syndrome, Hashimoto's thyroiditis, and Graves' disease in 1 patient each. Autoimmune diseases were not more frequent in patients with pseudotumoral (36%) or duct-destructive (19%) forms than in those with the usual form (5%, P = .06). Immunoglobulin G4 levels were increased in 2 of 6 in the pseudotumoral, 1 of 9 in the duct-destructive, and 0 of 12 patients in the usual group. Combining clinical and biochemical autoimmune parameters, 24 patients (40%) had at least 1 autoimmune marker or disease.
  
  
  CONCLUSIONS
  Clinical or biochemical autoimmune stigmata are present in 40% of patients with ICP. Autoimmune mechanisms may be frequent in idiopathic pancreatitis.
authors.affiliation: Fédération Médico-Chirurgicale d'Hépato-Gastro-Entérologie, Hôpital Beaujon, AP-HP, 92118 Clichy Cedex, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Nahon Uzan
authors.forename: Philippe
authors.initials: P
authors.lastname: Lévy
authors.forename: Dermot
authors.initials: D
authors.lastname: O'Toole
authors.forename: Nadia
authors.initials: N
authors.lastname: Belmatoug
authors.forename: Marie Pierre
authors.initials: MP
authors.lastname: Vullierme
authors.forename: Anne
authors.initials: A
authors.lastname: Couvelard
authors.forename: Philippe
authors.initials: P
authors.lastname: Ponsot
authors.forename: Laurent
authors.initials: L
authors.lastname: Palazzo
authors.forename: Aïcha
authors.initials: A
authors.lastname: Abbas
authors.forename: Pascal
authors.initials: P
authors.lastname: Hammel
authors.forename: Philippe
authors.initials: P
authors.lastname: Ruszniewski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood; D001327:Autoimmune Diseases / Q000473:pathology*; D002648:Child; D049448:Cholangiopancreatography, Magnetic Resonance; D015209:Cholangitis, Sclerosing / Q000150:complications; D003093:Colitis, Ulcerative / Q000150:complications; D019160:Endosonography; D005260:Female; D006111:Graves Disease / Q000150:complications; D050031:Hashimoto Disease / Q000150:complications; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D008297:Male; D008875:Middle Aged; D010180:Pancreatectomy; D016577:Pancreaticoduodenectomy; D050500:Pancreatitis, Chronic / Q000276:immunology* / Q000473:pathology*; D014057:Tomography, X-Ray Computed
chemical_list: D001323:Autoantibodies; D007136:Immunoglobulins