title: Anticyclic citrullinated peptide antibodies in rheumatoid and nonrheumatoid rheumatic disorders: experience with 1162 patients.
abstract: OBJECTIVE
  Anticyclic citrullinated peptide antibodies (anti-CCP) are considered specific markers of rheumatoid arthritis (RA) and have been included in the revised classification criteria for RA diagnosis. However, these antibodies have also been detected in patients with other types of chronic inflammatory rheumatism. Our objectives were to identify the prevalence of positive anti-CCP patients in non-RA diseases, to determine the diagnostic value of anti-CCP for the diagnosis of RA, to specify the clinical characteristics of non-RA patients positive for anti-CCP, and to determine the discriminatory value of the levels of anti-CCP in patients among the various diseases.
  
  
  METHODS
  We carried out an observational and descriptive study. All the determinations of anti-CCP requested by the 2 rheumatology departments at Cochin Hospital over a period of 18 months were analyzed. Such determinations were requested for 1162 patients in total. Anti-CCP levels were determined with the Euro Diagnostica ELISA kit, with values ≥ 25 U for this test being considered positive. The diagnosis of rheumatic conditions was the responsibility of the treating physician.
  
  
  RESULTS
  Anti-CCP antibodies were detected in 357 (30.7%) of the 1162 patients. The prevalence of anti-CCP was 292/417 (70.0%) in RA, 13/122 (10.6%) in patients with psoriatic arthritis, 13/62 (20.9%) in patients with unclassified rheumatism, 11/33 (33.3%) in patients with primary Sjögren syndrome, 5/30 (16.6%) in patients with systemic lupus erythematosus, 3/28 (10.7%) in patients with mixed connective tissue disorder, 3/36 (8.3%) in patients with systemic sclerosis, 7/44 (15.9%) in patients with juvenile arthritis, and 6/220 (2.7%) in patients with noninflammatory diseases. In the population of patients positive for anti-CCP, mean anti-CCP levels were 869.4 (± 978.4) U/ml, with no significant difference between RA [854.8 (± 959.8) U/ml] and any of the non-RA conditions [922.7 (± 1070.0) U/ml].
  
  
  CONCLUSIONS
  Anti-CCP are a hallmark of RA, but may be observed in other inflammatory, systemic, or mechanical diseases. In this large cohort of patients, the presence of second-generation anti-CCP (anti-CCP2) antibodies is useful in diagnosing RA (70% sensitivity, 91.3% specificity), but examining the levels of these antibodies does not appear to offer further discriminatory power among patients who are anti-CCP2-positive.
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital. judith.payet@cch.aphp.fr.
authors.forename: Judith
authors.initials: J
authors.lastname: Payet
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Claire
authors.initials: C
authors.lastname: Goulvestre
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Lisa
authors.initials: L
authors.lastname: Bialé
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Avouac
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Julien
authors.initials: J
authors.lastname: Wipff
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Chantal
authors.initials: C
authors.lastname: Job-Deslandre
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Batteux
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Maxime
authors.initials: M
authors.lastname: Dougados
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: André
authors.initials: A
authors.lastname: Kahan
authors.affiliation: From Paris Descartes University, Cochin Hospital, Rheumatology A and Rheumatology B, and Immunology Laboratory, Paris, France.J. Payet, MD, Rheumatology A; J. Avouac, PhD, Rheumatology A; J. Wipff, MD, Rheumatology A; C. Job-Deslandre, MD, Rheumatology A; A. Kahan, PhD, Rheumatology A; Y. Allanore, PhD, Rheumatology A; C. Goulvestre, MD, Immunology Laboratory; F. Batteux, MD, Immunology Laboratory; L. Bialé, MD, Rheumatology B; M. Dougados, MD, Rheumatology B, Paris Descartes University, Cochin Hospital.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Allanore
mesh_terms: D000328:Adult; D000368:Aged; D000888:Antibodies, Anti-Idiotypic / Q000097:blood*; D001171:Arthritis, Juvenile / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D015535:Arthritis, Psoriatic / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis* / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008947:Mixed Connective Tissue Disease / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D010456:Peptides, Cyclic / Q000276:immunology*; D012189:Retrospective Studies; D012216:Rheumatic Diseases / Q000097:blood / Q000175:diagnosis* / Q000276:immunology*; D012595:Scleroderma, Systemic / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D012680:Sensitivity and Specificity; D012859:Sjogren's Syndrome / Q000097:blood / Q000175:diagnosis / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D015415:Biomarkers; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide
keywords: ANTICYCLIC CITRULLINATED PEPTIDE ANTIBODIES; DIAGNOSIS; RHEUMATOID ARTHRITIS