[Diagnostic value of antibodies to modified citrullinized vimentin in early rheumatoid arthritis]

A hundred and two patients (18 males, 84 females; mean age, 50.3 +/- 12.3 years) diagnosed as having early rheumatoid arthritis (RA) were examined. A control group consisted of 189 patients with various rheumatic diseases and 30 healthy donors. The serum concentrations of antibodies to modified citrullinized vimentin (MCVA) and to cyclic citrullinized peptide2 (CCTP2A) were measured by enzyme immunoassay (EIA); rheumatoid factor (RF) IgM was determined by nephelometric immunoassay. In early RA, the level of MCVA (median, 49.6 U/ml; interquartile range, 0.9-249.3) was significantly higher than in the control group 1.65 U/ml; 0.3-19.7). There was a direct significant correlation between the levels of MCVA and CCTP2A (p = 0.9), as well as RF IgM (p = 0.6). The diagnostic efficiency of MCVA (area under the curve, 0.705; 95% confidence interval, 0.607-0.803) was higher than that of CCTP, (0.590; 0.467-0.714), but lower than that of RF IgM (0.813; 0.736-0.889). MCVA was comparable with CCTP, and RF IgM in sensitivity; however, it ranked below them in specificity (71%). Choice of the optimum upper normal range (30 U/ml) permits up to an 88% increase in MCVA specificity and the concurrent consideration of results of testing MCVA, CCTP2A, and RF IgM is attended by up to a 78% increase in sensitivity. EIA of MCVA is a sensitive and specific serological test for the diagnosis of early RA.