Anti-mutant citrullinated vimentin antibody in the diagnosis of rheumatoid arthritis

Abstract

Objective This study aimed to assess the diagnostic value of anti-mutated citrullinated vimentin (MCV) antibodies in rheumatoid arthritis (RA) and its correlation with disease progression, extra-articular manifestations and overlap syndrome. Methods Retrospective Studies. Clinical data of 837 patients in PekingUnionMedicalCollegeHospitalfrom June to August 2017 were collected, including the result of anti-MCV, anti-cyclic citrullinated peptide (anti-CCP) antibodies, rheumatoid factor (RF), erythrocyte sedimentation rate (ESR) and High-sensitivity-C-reactive protein (CRP). According to the 1987 American College of Rheumatology classification criteria for rheumatoid arthritis, there were 323 patients diagnosed with RA, including 59 males and 264 females with the average age of 51 years. According to whether the RA patients have overlap syndrome with other autoimmune disease (AID) or have extra-articular manifestations, 258 cases were categorized into RA group, including 47 males and 211 females with the average age of 50 years; 14 cases were categorized into the group of overlap syndrome, including 1 male and 13 females with the average age of 36 years; 51 cases were categorized into the group of extra-articular manifestations, including 11 males and 40 females with the average age of 59 years.According to 2010 rheumatoid arthritis classification criteria for destruction in joints, the radiographic changes were divided into 4 stages.There were 203 casesenrolled in our study, 88 caseswere fitted into early stage group (stage I)including 21 males and 67 females with the average age of 48 years; 115 caseswere fitted into progressive stage group, which compromisedstageⅡ (interim stage), stage Ⅲ (severe stage) and stage Ⅳ (final stage) cases, including 19 males and 96 females with the average age of 53 years. Mann-Whitney U test, χ2 test,Receiver operating characteristic (ROC) curves and Spearmancorrelation coefficientwere used in Statistical analysis. Results Ⅰ Amongdiagnosed RA patients, 199 (61.6%) cases were positive for anti-MCV, anti-CCP and RFsimultaneously, 42 (13%) cases were positive for anti-MCV, which was higher than anti-CCP positive (1 cases, 0.3%) or RF positive (7cases, 2.2%). The difference was statistically significant(P<0.001, P<0.001). Ⅱ ROC was calculated and MCV=35.95 U/ml was used as best-fit cut-off value. The AUC for anti-MCV was 0.867, while the sensitivity was 80.5% and specificity was 80.9%. Ⅲ The detection levels of anti-MCV (682.8 (106.4-1000.0)), anti-CCP (407 (4.0-1536.0)) and RF (82.8 (21.1-244.9)) in the group of progressive stage were higher than those in the group of early stage (114.5 (28.5-1000.0), 62.5 (5.0-1020.7), 50.1 (6.7-127.1)), which showed a significant difference (P<0.05, P<0.05, P<0.05). The anti-MCV, anti-CCP and RF were positively related to the degree of joint destruction (r=0.229, P<0.05; r=0.187, P<0.05; r=0.167, P<0.05); anti-MCV and anti-CCP were positively related to extra-articular manifestation (r=0.152, P<0.05; r=0.136, P<0.05). Conclusion Anti-MCV antibodies are more sensitive in patients with RA, and have complementary diagnostic value for anti-CCP and RF-negative patients; high levels of anti-MCV and anti-CCP in RA patients are associated with RA progression and extra-articular involvement. Key words: Arthritis, rheumatoid; Autoantibodies; Peptides, cyclic; Vimentin