Effects of Infliximab on Rheumatoid Factor & Anti-cyclic Citrullinated Peptide Antibodies in Patients with Rheumatoid Arthritis

Background: Anti-cyclic citrullinated peptide antibodies (ACPA) and rheumatoid factor (RF) are two important investigations that help in confirming the diagnosis and may help deciding strategies for the treatment. This study’s aim is to investigate the effect of infliximab, a tumor necrosis factor inhibitor on ACPA and RF in patients with rheumatoid arthritis.

Patients and Method:Thirty five Iraqi patients with established RA, enrolled in this study during September 2013-May 2014. They received 3 mg/kg infliximab intravenously at weeks 0, 2, 6, and every 8 weeks thereafter in combination with methotrexate (15-20) mg. At baseline, week 24, CRP and ESR were determined and the disease activity score (DAS28) was calculated. Serum samples collected at the same time points were used to measure ACPA, and IgM-RF (ELISA).

Results:RF mean at the first visit was (106.1±25.2) IU/ml and at the second visit it reduced to (60.1±14.6) IU/ml and the difference was statistically significant, (P=0.038). ACPA mean was (466.5±61.4) U/ml at the first visit reduced significantly to reach (241.9±36.6) U/ml at the second visit (P<0.001). A dramatic and significant change had been found in the disease activity; (P<0.001) mean DAS 28 was (5.7±1.1) at the first visit with a range of (2.7– 8.6), at the second visit the mean was (4.5±1) and the range was (2.04–6.4).

Conclusions:Anti-TNF a treatment in RA cause decrease in serum titers of RF and ACPA in patients with clinical improvement.