From the Guidelines
Anti-CCP is a highly specific test for rheumatoid arthritis, with a specificity of 95-98%, making it a valuable diagnostic tool for early diagnosis and treatment. The test detects antibodies against citrullinated proteins, which are commonly found in patients with rheumatoid arthritis (RA) 1. A positive anti-CCP result strongly suggests RA, often appearing years before symptoms develop, allowing for earlier diagnosis and treatment.
Key Points
- The test is particularly useful when combined with rheumatoid factor (RF) testing, as some patients may be positive for one but not the other 1.
- Anti-CCP positivity also indicates a higher likelihood of developing more severe, erosive joint disease.
- The test requires a simple blood draw and results are typically reported as negative, low-positive, or high-positive.
- Higher antibody levels generally correlate with more aggressive disease.
Treatment and Evaluation
If you have a positive anti-CCP test, you should be evaluated by a rheumatologist promptly, as early treatment with disease-modifying antirheumatic drugs (DMARDs) can significantly improve outcomes and prevent joint damage 1. The treatment approach should include aggressive treatment modification to achieve targets based on a composite disease activity score, such as the Disease Activity Score, which leads to superior clinical outcomes 1.
Disease Activity Assessment
The assessment of disease activity should include quantitative evaluation of patient-reported outcomes, including pain, the patient Global Assessment of Disease Activity score, and the Health Assessment Questionnaire Disability Index score 1. The physician, trained nurse, or physician assistant should perform the evaluator global assessment, which includes physical examination of the joints and evaluation of the number of tender and swollen joints on the basis of the 28-joint count 1.
From the Research
Anti-CCP Antibodies
- Anti-CCP antibodies are used for the diagnosis of rheumatoid arthritis (RA) 2, 3
- The presence of anti-CCP antibodies has a higher specificity and diagnostic power than rheumatoid factor (RF) 4
- However, anti-CCP antibodies are less informative than RF in monitoring the course of the disease in patients under treatment 4
Disease Activity and Anti-CCP Antibodies
- There is a weak correlation between anti-CCP antibody levels and disease activity in patients with RA 2
- The individual correlation between anti-CCP antibody levels and disease activity can vary greatly, with some patients showing a strong positive or negative correlation 2
- In patients with erosive RA, the correlation between anti-CCP antibody levels and disease activity is more positive than in patients with non-erosive RA 2
Treatment and Anti-CCP Antibodies
- The use of biologic disease-modifying antirheumatic drugs (bDMARDs) can reduce anti-CCP antibody levels in patients with RA 4
- However, the reduction in anti-CCP antibody levels does not provide additional predictive information in the follow-up of patients with RA treated with bDMARDs 4
- The cost-effectiveness of bDMARDs compared to conventional disease-modifying antirheumatic drugs (cDMARDs) is uncertain, with high incremental costs per quality-adjusted life-year (QALY) gained 5
Other Conditions and Anti-CCP Antibodies
- High titers of anti-CCP antibodies can be found in patients with sacroiliitis or reactive arthritis post-E. coli infection, suggesting an overlap between RA and seronegative spondyloarthritis (SpA) 6
- The presence of anti-CCP antibodies in patients with SpA or reactive arthritis may indicate a more severe disease course or a higher risk of developing RA 6