Introduction: Autoantibodies in rheumatoid arthritis (RA) are useful both for diagnosis and
prognosis. Anti-cyclic citrullinated peptide (CCP) antibodies have recently been shown to
predict development of RA as well as poor outcome in early arthritis. Data on their role in
established RA is limited.
Aim of the work: To determine the frequency of anti-CCP and rheumatoid factor
positivities and their associations with disease activity in patients with RA.
Patients and methods: A cross-sectional study was made on 83 patients with RA. The
following values were assessed: erythrocyte sedimentation rate (ESR), C-reactive protein
(CRP), complete blood count (CBC), rheumatoid factor (RF), anti-CCP, swollen and tender
joint counts, Disease Activity Score 28 (DAS 28), Health Assessment Questionnaire score
(HAQ), Visual analogue scale (VAS) of pain and modified Larsen score of joint damage.
Results: Seventy-eight percent of RA patients were RF positive from which 8.4% were
negative for anti-CCP. There was a significant correlation between RF positivity and age (p
<or= 0.002), disease duration (p <or= 0.001), VAS (p <or= 0.001), swollen joint count (p
<or= 0.01), DAS 28 (p <or= 0.001), HAQ score (p <or= 0.002), anti-CCP (p <or= 0.001),
CRP (p <or= 0.001), ESR (p <or= 0.001), and modified Larsen score (p <or= 0.001). There
was no correlation between positive RF and duration of morning stiffness and tender joint
count. Seventy-seven percent of RA patients were anti-CCP positive, from which 7.2 % were
negative for RF. There was a significant correlation between anti-CCP positivity and age (p
<or= 0.03), disease duration (p <or= 0.001), VAS (p <or= 0.04), HAQ score (p <or= 0.03),
RF (p <or= 0.001), CRP (p <or= 0.003), ESR (p <or= 0.02), and modified Larsen score (p
<or= 0.006). There was no correlation between anti-CCP and duration of morning stiffness,
tender and swollen joint counts and DAS 28.
Conclusion: Anti-CCP antibodies are present in the majority of patients with established
RA including seronegative patients. Both RF and anti-CCP positivities were significantly
associated with some parameters of both disease activity and severity; however RF positivity
was associated with these parameters more significantly than did anti-CCP.