Application of anti-cyclic citrullinated peptide in diagnosis of rheumatoid arthritis

Objective To investigate the clinical value of anti-cyclic citrullinated peptide used in diagnosis of rheumatoid arthritis.Methods The levels of anti-cyclic citrullinated peptide and rheumatoid factor in serum obtained from 109 patients with rheumatoid arthritis,42 patients with other rheumatic immunological diseases and 30 healthy people as control were measured by ELISA.Results In rheumatoid arthritis diagnosis,the rates of sensitivity of anti-cyclic citrullinated peptide and rheumatoid factors were 62.4% and 70.6%,showing no significant difference between them(x2=3.5,P0.05).But the specificity of anti-cyclic citrullinated peptide was 95.8% and obviously higher than that of rheumatoid factor(81.9 %)(x2=38.2,P0.01).The sensitivity of anti-cyclic citrullinated peptide combined with rheumatoid factor test dropped 56.0%,but the specificity of that increased to 98.6%,with a coincidence rate of 78.9%.Conclusions Anti-cyclic citrullinated peptide is high ly specific in diagnosis of rheumatoid arthritis s.