Anti-mutated citrullinated vimentin antibodies as a biomarker for interstitial lung disease in patients with rheumatoid arthritis.

Objectives: We aimed to assess the anti-mutated citrullinated vimentin (anti-MCV) antibodies in RA patients' serum and to explore their association with interstitial lung disease (ILD).

Methods: Eighty rheumatoid arthritis (RA) patients and forty healthy controls were included in this case-control study. Of these patients, forty had ILD, and forty without ILD. Patients were subjected to clinical and laboratory assessment, measurement of anti-MCV serum levels by ELISA, X-ray of hands and feet, pulmonary function tests, and high-resolution computed tomography (HRCT) of the chest.

Results: Increased serum level of anti-MCV antibodies was found in RA patients compared with the controls and in RA patients with ILD compared to those without ILD. The serum anti-MCV level was correlated positively with disease activity score 28 (DAS28), Larsen, erythrocyte sedimentation rate (ESR), and anti-citrullinated peptides antibodies (ACPA) and negatively with the diffusing capacity for carbon monoxide (DLCO), and forced vital capacity (FVC). Patients' age, disease duration, ACPA level, anti-MCV level, and anti-MCV positivity were predictors of ILD in our patients. At the 42.5 U/ml cut-off, the anti-MCV antibodies have 78.8% sensitivity and 80% specificity for RA, and at the 155.5 U/ml cut-off, their sensitivity is 80%, and their specificity is 75% for ILD.

Conclusion: Anti-MCV antibodies are increased in RA patients with ILD with high sensitivity and specificity; thus, they may represent a promising marker for early detection and prediction of RA-related ILD. In addition, anti-MCV antibodies positively correlate with the Larsen score; hence, they may be a valuable serological marker for predicting joint damage in RA patients. More research with large sample sizes is recommended to support our findings.