Diagnostic value of anti-MCV antibodies in differentiating early inflammatory arthritis

Objectives: To evaluates the diagnostic performance of the anti-CCP2, anti-CCP3 and anti-mutated citrullinated vimentin (anti-MCV) tests in differentiating rheumatoid arthritis (RA) from other forms of arthritis in a clinical setting of early arthritis. Methods: In 917 patients with recent-onset arthritis (566 RA, 351 other diseases) and in 99 healthy controls the anti-MCV, anti-CCP2 and anti-CCP3.1 tests were performed and the test characteristics compared. Results: Comparison of the tests for differentiating RA from other causes of arthritis showed a lower specificity for anti-MCV (82.9%) than for anti-CCP2 (93.4%) and anti-CCP3.1 (90.0%). Similarly, the positive likelihood ratio for anti-MCV was also lower (3.6, compared with 8.7, 5.8 for anti-CCP2 and anti-CCP3.1). The anti-MCV test had a higher sensitivity (62% vs 56.9% and 58.1%, respectively). In psoriatic arthritis, spondyloarthropathy and other arthritis anti-MCV antibodies had a prevalence of 15.2%, 13.9% and 19.4%. Conclusion: The diagnostic performance of the anti-MCV test in the differential diagnosis of early arthritis is lower than that of the anti-CCP tests.