title: Anticyclic citrullinated peptide antibody and rheumatoid factor in south Tunisian patients with rheumatoid arthritis: association with disease activity and severity.
abstract: OBJECTIVE
  To explore relationships between immunological status, clinical features, radiographic damage, disease activity, and functional disability in Tunisian patients with rheumatoid arthritis (RA).
  
  
  METHODS
  The study was carried out in 112 patients with RA. Demographic characteristics, disease duration, disease activity score 28 (DAS28), the Health Assessment Questionnaire (HAQ), and the Sharp/van der Heijde score were collected. Anticyclic citrullinated peptide antibody (anti-CCP) and rheumatoid factor (RF) were performed.
  
  
  RESULTS
  We found that anti-CCP positivity was associated with longer disease duration (P = 0.001), presence of RF (P = 4.89 × 10(-8) ), and night pain positivity (P = 0.025). Patients with positive RF had more night pain and higher anti-CCP positivity (for all P ≤ 0.05). Anti-CCP titer was correlated with disease duration (P = 0.034) and Sharp total score (P = 1.2 × 10(-4) ). Moreover, there was a significant correlation between RF and anti-CCP antibodies titers (P = 0.011). Indeed, DAS28 correlated with HAQ (P = 1.8 × 10(-7) ) and morning stiffness duration (P = 0.045). In multivariate regression analysis, the main factors associated with anti-CCP titers were radiographic damage (P = 1.625 × 10(-4) ) and RF (P = 0.013). For DAS28, only HAQ (P = 2.9 × 10(-4) ) was associated.
  
  
  CONCLUSIONS
  These findings suggest that anti-CCP antibodies are associated with RF and more severe joint damage. Moreover, disease activity is associated with functional disability.
authors.affiliation: Laboratory of Human Molecular Genetics, Faculty of Medicine, University of Sfax, Sfax, Tunisia.
authors.forename: Mariem Ben
authors.initials: MB
authors.lastname: Hamad
authors.forename: Sameh
authors.initials: S
authors.lastname: Marzouk
authors.forename: Neila
authors.initials: N
authors.lastname: Kaddour
authors.forename: Hatem
authors.initials: H
authors.lastname: Masmoudi
authors.forename: Faiza
authors.initials: F
authors.lastname: Fakhfakh
authors.forename: Ahmed
authors.initials: A
authors.lastname: Rebai
authors.forename: Zouhir
authors.initials: Z
authors.lastname: Bahloul
authors.forename: Abdellatif
authors.initials: A
authors.lastname: Maalej
mesh_terms: D000906:Antibodies / Q000097:blood* / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000276:immunology*; D001323:Autoantibodies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000097:blood* / Q000276:immunology*; D012044:Regression Analysis; D012217:Rheumatoid Factor / Q000097:blood* / Q000276:immunology*; D012720:Severity of Illness Index; D014416:Tunisia
chemical_list: D000906:Antibodies; D001323:Autoantibodies; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor
keywords: DAS28; anti-CCP antibodies; rheumatoid arthritis; rheumatoid factor