title: Autoantibodies in early rheumatoid arthritis: Brasília cohort: results of a three-year serial analysis.
abstract: The diagnostic and prognostic value of the serial measurement of antibodies, such as rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and anti-citrullinated vimentin (anti-Sa) antibodies, has not been defined in early rheumatoid arthritis (ERA).
  
  
  OBJECTIVE
  To prospectively assess the presence of RF, anti-CCP, and anti-Sa in ERA patients.
  
  
  METHODS
  Forty ERA (less than 12 months) patients of the Brasília cohort were evaluated and followed up for three years. Both clinical and demographic data were recorded, in addition to the results (ELISA) of RF (IgM, IgG, and IgA), anti-CCP (CCP2, CCP3, and CCP3.1), and anti-Sa at the baseline assessment and after 3, 6, 12, 18, 24 and 36 months of follow-up. The results were compared by use of Student t test and paired t test.
  
  
  RESULTS
  The patients' mean age was 45 years, and 90% of them were female. At the time of diagnosis, RF was identified in 50% of the patients (RF IgA, 42%; RF IgG, 30%; and RF IgM, 50%), anti-CCP in 52.5% (no difference between CCP2, CCP3, and CCP3.1), and anti-Sa in 10%. After three years, no difference was observed in RF and anti-CCP prevalence, but anti-Sa increased to 17.5% (P = 0.001).
  
  
  CONCLUSIONS
  Repeated RF and anti-CCP measurement, including different isotypes, during three years of follow-up showed no significant changes. The third generation of anti-CCP assays did not increase the diagnostic value of the second-generation assays.
authors: Serviço de Reumatologia Clínica Médica, Universidade de Brasília. liciamhmota@yahoo.com.br
authors: Licia Maria Henrique
authors: LM
authors: da Mota
authors: Leopoldo Luiz Dos
authors: LL
authors: Santos Neto
authors: Ivânio Alves
authors: IA
authors: Pereira
authors: Rufus
authors: R
authors: Burlingame
authors: Henri A
authors: HA
authors: Ménard
authors: Ieda Maria Magalhães
authors: IM
authors: Laurindo
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D001938:Brazil; D002956:Citrulline / Q000031:analogs & derivatives* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D011446:Prospective Studies; D012217:Rheumatoid Factor / Q000276:immunology*; D013997:Time Factors; D014746:Vimentin / Q000276:immunology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D010456:Peptides, Cyclic; D014746:Vimentin; C487763:cyclic citrullinated peptide; D002956:Citrulline; D012217:Rheumatoid Factor