CLINICAL VALUE OF THREE KINDS OF SEROLOGICAL INDEXES IN THE AUXILIARY DIAGNOSIS OF RHEUMATOID ARTHRITIS AND INFLUENCE ON THE DISEASE SEVERITY

Jiao Shi, Jia Xu, Jianguang Zhu, Zhinong Wu, Wei Xiao^*

Department of Clinical Laboratory, Xianning Central Hospital,The First Affiliated Hospital of Hubei University of Science and technology, Xianning, Hubei, 437000, PR China

Objective: To investigate the clinical value of rheumatoid factor, anti-cyclic citrulline peptide antibody and anti-mutant citrulline vimentin antibody in the auxiliary diagnosis of rheumatoid arthritis and influence on the disease severity. 

Methods: Clinical data of 419 patients were retrospectively chosen in the period from January 2016 to June 2019 and ESR, CRP, rheumatoid factor, anti cyclic citrullinated peptide antibody and anti mutant citrullinated vimentin antibody of all patients were detected. Patients were divided into different groups according to the disease type, RA complications and the joint injury degree. The diagnostic efficacy of rheumatoid factor, anti cyclic citrullinated peptide antibody and anti mutant citrullinated vimentin antibody in rheumatoid arthritis were analyzed. 

Results: The positive rate of anti-mutant citrulline vimentin antibody alone was significantly higher than rheumatoid factor and anti cyclic citrulline peptide antibody (P<0.05). ROC curve analysis showed that AUC of anti-mutant citrulline vimentin antibody was the highest; when the best cut-off value is 36.24u/ml, the sensitivity of anti-mutant citrulline vimentin antibody is higher than anti-cyclic citrullinated peptide antibody and rheumatoid factor, the specificity of anti-mutant citrulline vimentin antibody is lower than anti-cyclic citrullinated peptide antibody, and the positive predictive value of anti-mutant citrulline vimentin antibody is lower than anti-cyclic citrullinated peptide antibody (P<0.05). The positive rate of anti-mutant citrulline vimentin antibody in patients with rheumatoid arthritis was significantly higher than autoimmune system diseases and other types of bone and joint diseases (P<0.05). The positive rate of anti-mutant citrulline vimentin antibody in patients with rheumatoid arthritis was significantly higher than autoimmune system diseases and other types of bone and joint diseases (P<0.05). The positive rate of anti-mutant citrulline vimentin antibody in patients with autoimmune diseases was significantly higher than anti-cyclic citrulline peptide antibody and rheumatoid factor (P<0.05). The positive rate of anti-mutant citrulline vimentin antibody in other types of bone and joint diseases was significantly higher than anti-cyclic citrulline peptide antibody and rheumatoid factor (P<0.05). The levels of rheumatoid factor, anti-cyclic citrullinated peptide antibody, anti-mutant citrullinated vimentin antibody, ESR and CRP in patients with joint injury in advanced stage were significantly higher than in early stage (P<0.05). Rheumatoid factor, anti-cyclic citrullinated peptide antibody and anti-mutant citrullinated vimentin antibody were positively correlated with joint damage degree (r=0.25, 0.19, 0.17, P<0.05). The results of Spearman analysis showed that there was no correlation between rheumatoid factor, anti-cyclic citrullinated peptide antibody and anti-mutant citrullinated vimentin antibody and the occurrence of overlap syndrome of rheumatoid arthritis (P>0.05). Anti-cyclic citrulline peptide antibody and anti-mutant citrulline vimentin antibody are positively correlated with the extraarticular injury (P<0.05). There was no correlation between rheumatoid factor and extraarticular injury (P>0.05). 

Conclusion: Anti-mutant citrulline vimentin antibody in the diagnosis of rheumatoid arthritis possess high sensitivity. It can be used for the diagnosis of rheumatoid factor and anti-cyclic citrullinated peptide antibody negative population. Patients with high levels of anti-cyclic citrullinated peptide antibody and anti-mutant citrullinated vimentin antibody have higher risk of rheumatoid arthritis and extraarticular injury.