Value of anti-cyclic citrullinated peptide antibodies and magnetic resonance imaging in early rheumatoid arthritis

ABSTRACT

To assess the value of the presence of anti-cyclic citrullinated peptide antibody [anti-CCPAb] as well as magnetic resonance imaging [MRI] in early rheumatoid arthritis [RA]. The study was performed on twenty early RA patients [with disease duration <1 year] diagnosed according to the 1987 ACR classification criteria. They underwent full history taking and thorough clinical examination. Anti-CCPAb was assessed with ELISA technique. MRI study was done for both wrist joints and hands of all patients and evaluated according to the OMERACT 2002 RAMRIS scoring system. Disease activity was assessed with CRP and 28 joint disease activity score [DAS28]. Rheumatoid factor [RF] IgM was analyzed with latex agglutination. We divided the patients according to the presence or absence of anti-CCP antibodies into two groups Eleven [55%] patients were positive for anti-CCP and 9 [45%] patients were anti-CCP negative. Comparison between the two groups revealed that there was a highly statistical significant difference as regards the CRP level and DAS28 score [p<0.001]. There was a statistically significant difference in the initial presentation between the two groups; in anti-CCP positive patients symptoms started more often in the upper limbs while the anti-CCP negative group they often presented in both upper and lower limbs. Bone marrow edema was more frequent in patients with positive than those with negative anti-CCP-Ab with a highly statistical significant difference [p<0.001]. The highest global scores for bone edema were seen in triquetral and lunate bones. The prevalence and severity of synovitis as well as the MRI scoring of bone erosions did not differ significantly between the two groups [p>0.05]. The highest global score of erosions was located in the same sites in the wrist and MCP joints. Tenosynovitis was observed nearly equally in both groups of patients. Global scores of tenosynovitis in both groups were high in the extensor tendons of the wrist and in the flexor tendons of the MCP joints. The study showed the importance of the presence of positive anti-CCPAb at baseline and its high association with greater disease activity [DAS28], higher levels of CRP, and bone marrow edema as an indicator of future bone erosion in early RA. MRI can be added as a useful tool for evaluation of early RA. This aspect is important because an early diagnosis of RA may modify the therapeutic strategy substantially, suggesting the use of more aggressive pharmacological agents that can delay progression of joint damage and thus substantially change the natural history of the disease