role of rheumatoid factor and anti-cyclic citrullinated peptide antibody in diagnosis of rheumatoid arthritis

ABSTRACT

Rheumatoid Factor [RF] occurs in 70- 90% of patients with established rheumatoid arthritis [RA]. Anti-cyclic Citrullinated peptide antibody [Anti-CCP] detection may be used to confirm the diagnosis of RA in patients with uncharacterized chronic inflammatory arthritis. This study is an attempt to evaluate the role of RF and anti-CCP in the diagnosis and prognosis of rheumatoid arthritis. Blood samples were obtained from 55 patients with established RA and 55 healthy controls. Anti-CCP and RF were measured by ELISA and nephelometry. The patient's demographics, disease duration, DMARDs usage, ESR and radiographic abnormalities were recorded. Fifty five RA patients and 55 healthy age and sex matched controls were enrolled. Odd ratio [OR] was 87.42 [C 1=11.2-680.1] for RF and 27.48 [6/08-124/09] for Anti- CCP. Five patients had used more than 3 DMARDs; all of them were RF positive and 4 were also anti-CCP positive. Eleven patients had erosions in their radiographs; 10 of them were seropositive for RF and 9 positive for anti-CCP. Our study suggests that despite lack of specificity, RF continues to be a central part of the definition of RA due to favorable sensitivity profile and the combined use of RF. Also, anti-CCP is a more powerful diag-nostic and prognostic tool