Frequency of Positive Anti-CCP Antibodies in Rheumatoid Arthritis Patients with Negative Rheumatoid Factor

Abstract

Background: Rheumatoid arthritis (RA) is a polyarticular autoimmune disease that affects about 1% of the adult population. The disease is characterized by synoviocyte hyperplasia, mainly synovial fibroblasts, resulting in bone and joint destruction. Recent studies have shown that cytokines and other systemic inflammation mediators have a key role in the development ofrheumatoid arthritis. Recently, Anti-Citrullinated Protein Antibodies (anti-CCP) have come into use for the diagnosis of rheumatoid arthritis (RA). It has been reported that anti-CCP has quite a high specificity for RA (98%), together with sensitivity similar to that for rheumatoid factor (RF). The study aimed to determine the frequency of positive anti-CCP antibodies in rheumatoid arthritis patients with negative rheumatoid factor.

Methods: 91 patients (both male and females) aged 40-70years with negative RF were clinically diagnosed with rheumatoid arthritis. Patients with positive rheumatoid factor and joint injuries were disclaimed. The consultant pathologist used a second-generation enzyme-linked immunosorbent assay (ELISA) to assess the serum levels of anti-CCP antibodies, >20IU/ ml is considered positive p-value of 0.05 were considered statistically significant.

Results: In the study, the age range was 40 to 70 years, averaging 53.44 ± 7.16 years. 59 (64.84%) of the patients were between the ages of 40 and 55. Of 91 patients, 56 (61.54%) were women, and 35 (38.46%) were men with aratio of 1.6:1 man to women. In patients with negative rheumatoid factors, 27 (40.66%) patients were found to have the levels of positive anti-CCP antibodies.

Conclusion: Patients with negative rheumatoid factor showed the high frequency of positive anti-CCP.