From the Guidelines
For patients already diagnosed with rheumatoid arthritis (RA), routine testing of rheumatic profile and cyclic citrullinated peptide (CCP) IgG antibodies is not indicated unless there are specific clinical scenarios that warrant re-evaluation, such as a change in clinical presentation or uncertainty about the initial diagnosis. The management of RA focuses on monitoring disease activity, adjusting treatment strategies, and preventing long-term damage. Key factors in determining the prognosis and guiding treatment decisions include the presence of autoantibodies like rheumatoid factor and anti-CCP antibodies, particularly at high levels, as well as high disease activity and early occurrence of erosions 1.
The initial antibody status, especially anti-CCP positivity, has prognostic value in predicting disease severity and guiding treatment intensity, but serial measurements do not correlate well with disease activity 1. Therefore, resources are better directed toward monitoring tools that directly reflect current disease activity and treatment response, such as clinical assessment, inflammatory markers like ESR and CRP, and imaging studies.
In the context of RA management, the focus should be on achieving low disease activity or remission through the use of disease-modifying antirheumatic drugs (DMARDs), biologics, and other therapies, rather than on repeated testing of rheumatic profiles and anti-CCP antibodies unless clinically warranted 1. This approach is supported by guidelines and expert opinions that emphasize the importance of tailored treatment strategies based on individual patient factors and disease characteristics.
From the Research
Rheumatoid Arthritis Diagnosis
- Rheumatoid arthritis (RA) is a severe, progressive, systemic inflammatory disease of unknown etiology, and early diagnosis is crucial to prevent irreversible damage 2.
- The American College of Rheumatology and the European League Against Rheumatism included anti-cyclic citrullinated peptide (anti-CCP) antibodies in the new criteria for RA in 2009, highlighting their importance in diagnosis 2.
Role of Anti-CCP Antibodies
- Anti-CCP antibodies have higher sensitivity and specificity compared to rheumatoid factor (RF) for diagnosing RA, with a sensitivity of 78.5% and specificity of 95.9% and 97.9% for other rheumatic diseases and chronic inflammatory disease patients, respectively 2.
- The presence of anti-CCP antibodies is associated with clinical signs of disease severity, such as functional disability, presence of erosions, and absence of clinical remission 3.
Indications for Rheumatic Profile and Anti-CCP IgG Ab
- For patients already known to have RA, the rheumatic profile and anti-CCP IgG Ab may not be necessary for diagnosis, but can be useful for monitoring disease activity and predicting treatment response 4, 5.
- The combination of anti-CCP antibodies with IgA RF or the combination of the three serological markers (anti-CCP, IgA RF, and IgM RF) can increase specificity in diagnosing RA 3.
Diagnostic Performance
- The diagnostic performance of IgA and IgM anti-CCP2 antibodies is similar to that of IgG anti-CCP2, with specificity of 95.8%, 95.8%, and 91.6%, respectively 5.
- The combination of RF and anti-CCP antibody detection has a sensitivity of 90.2%, specificity of 83.3%, and accuracy of 89.5% for diagnosing RA 6.