Anti-MCV and anti-CCP antibodies-diagnostic and prognostic value in children with juvenile idiopathic arthritis (JIA).

The goal of the study was to evaluate the diagnostic and prognostic value of anti-mutated citrullinated vimentin (anti-MCV) antibodies in juvenile idiopathic arthritis (JIA) comparing to anti-cyclic citrullinated peptide (anti-CCP). Thirty children with confirmed JIA diagnosis and 20 children as a control group were included into the study. Serum and synovial fluid levels of anti-CCP, anti-MCV, and immunoglobulin M rheumatoid factor (IgM-RF) antibodies have been assessed. Anti-MCV was positive in 11/30 (36.6 %), whereas anti-CCP positivity was found in 12/30 (40 %) children with JIA. Among 11 children with JIA positive for anti-MCV, five (45.5 %) were also positive for anti-CCP and among 18 JIA children negative for anti-CCP, six (33.33 %) were also anti-MCV positive. Six out of 30 JIA children were found to be IgM-RF positive. In general, two out of all those 11 anti-MCV-positive patients demonstrated oligoarthritis and 9/11 had polyarticular type of onset. Anti-MCV serum concentration correlated positively with anti-CCP (p = 0.004). Almost 60 % of children in early stage of JIA were anti-MCV positive. Levels of anti-CCP antibodies correlated positively with the disease activity (p = 0.0014) and radiological outcome (p = 0.00017). In all synovial fluid samples, the concentration of autoantibodies was under the cut-off values. The results of our study indicate that anti-MCV as well as anti-CCP antibodies may be helpful in the diagnosis of JIA, especially in the early course of the disease. Anti-MCV antibodies could identify a group of children with JIA which is negative for anti-CCP antibodies and RF. However, it appears that in JIA, anti-CCP rather than anti-MCV antibodies have impact on radiographic changes.