PT - JOURNAL ARTICLE AU - Lilla Soós AU - Zoltán Szekanecz AU - Zoltán Szabó AU - Andrea Fekete AU - Margit Zeher AU - Ildikó F Horváth AU - Katalin Dankó AU - Anikó Kapitány AU - Anikó Végvári AU - Sandor Sipka AU - Gyula Szegedi AU - Gabriella Lakos TI - Clinical evaluation of anti-mutated citrullinated vimentin by ELISA in rheumatoid arthritis. DP - 2007 Aug 01 TA - The Journal of Rheumatology PG - 1658--1663 VI - 34 IP - 8 4099 - http://www.jrheum.org/content/34/8/1658.short 4100 - http://www.jrheum.org/content/34/8/1658.full SO - J Rheumatol2007 Aug 01; 34 AB - OBJECTIVE: Anti-cyclic citrullinated peptide (CCP) antibodies have emerged as sensitive and specific serological markers of rheumatoid arthritis (RA). However, antibodies to several other citrulline-containing proteins, including citrullinated fibrin and vimentin, have been detected in patients with RA, suggesting that citrulline is an essential constituent of autoantigens for RA-specific autoantibodies. We examined the diagnostic performance of the newly developed anti-mutated citrullinated vimentin (MCV) antibody assay. METHODS: Concentrations of anti-MCV, anti-CCP2, and rheumatoid factors (RF) were determined in the sera of 237 individuals: 119 patients with RA and 118 controls, including patients with other rheumatic diseases and healthy subjects. Diagnostic properties were compared by receiver-operating characteristic curve analysis. RESULTS: Using manufacturer's recommended cutoff values, sensitivity and specificity of anti-MCV antibodies were 75.6% and 91.5% in RA, compared to 66.4% and 98.3% for anti-CCP2. Introducing cutoff values to obtain the same 95% specificity resulted in decreased sensitivity of the anti-MCV test (69.7%) and increased sensitivity of the anti-CCP2 test (74.8%). At optimal cutoff levels, 29.4% of IgM RF-negative cases as well as 13.3% of anti-CCP2-negative cases in the RA group were anti-MCV-positive. Double-positivity for anti-MCV and anti-CCP2 provided 98.3% specificity with 97.5% positive predictive value in RA. CONCLUSION: Overall, the performance of the novel anti-MCV ELISA for the diagnosis of RA is similar to that of the anti-CCP2 test [area under the curve 0.853 (95% CI 0.801-0.905) vs 0.910 (95% CI 0.873-0.946); p not significant]. As the diagnostic spectrum of the anti-MCV assay is somewhat different from that of anti-CCP2, the combined application of the 2 assays can improve the laboratory diagnostics of RA.