[The analytic and diagnostic characteristics of the national test system detecting cyclic citrullinated peptide antibodies].

The clinical signifcance of serodiagnostic assay of rheumatoid arthritis increased nowadays. This is a reason to include the citrullinated antigens' antibodies into the new criteria of diagnostics ACR/EULAR 2010. The approbation of national test system detecting the cyclic citrullinated peptide antibodies was implemented. The analysis was applied to 211 blood serum samples taken of 50 blood donors, 60 patients with rheumatoid arthritis, 66 patients with other rheumatoid diseases. In addition, 35 samples were concurrently analyzed with the comparative test system (CCP2 Euroimmun, Germany). The referential meanings of standard limits were established on the basis of results of study of samples taken from healthy blood donors. When the standard limit was less than 10 arbitrary units the sensitivity made up 75% and the specificity--87.9%. In the case of higher values of citrullinated antigens' antibodies which are more than 15 arbitrary units, the sensitivity made up 68% and the specificity--93.1%. The results of comparing with the comparative test system characterized by high convergence made up 94% (33 out of 35), but the comparative test system detected citrullinated antigens' antibodies in 2 samples. The positive qualitative results of both methods analysis of autoantibodies weakly correlated with one another (r = 0.14). The results testify that the parameters of national test system correspond to the publication data concerning the second generation methods of cyclic citrullinated peptide antibodies detection though yield to the best foreign analogues.