Antibodies targeting mutated citrullinated vimentin in patients with psoriatic arthritis

Antibodies against mutated citrullinated vimentin (anti-MCV) are of a comparable diagnostic value in rheumatoid arthritis (RA) as antibodies targeting citrullinated peptides (anti-CCP). Anti-CCP are present in up to 15% of psoriatic arthritis (PsA) patients, while the prevalence of anti-MCV in PsA patients has been poorly investigated. The aim of the present study was to assess the prevalence and relevance of anti-MCV antibodies in PsA patients. The study included 56 PsA patients. Clinical features, disease activity, and functional ability were noted by an experienced rheumatologist. Serum samples of all patients were analyzed for anti-MCV and anti-CCP antibodies using enzyme-linked immunosorbent assay. Data on 92 patients with RA, 44 patients with other inflammatory rheumatic diseases, and 107 healthy controls from a previous study were used to compare the prevalence of anti-MCV antibodies in PsA patients. Anti-MCV antibodies were positive in only two out of 56 (3.6%) PsA patients, which was significantly lower compared to RA patients (63%). The anti-MCV level was moderately positive and borderline in one patient each. Both patients had asymmetric polyarthritis, dactylitis, moderate to high disease activity, and were anti-CCP and rheumatoid factor (RF) negative. There was no significant difference in anti-MCV levels according to clinical subtypes of PsA and no correlation of anti-MCV levels with anti-CCP, RF, disease activity variables, and functional ability indices. According to study results, anti-MCV antibodies can be detected in a very small proportion of PsA patients with polyarthritic disease and are primarily related to the polyarthritic pattern rather than the specific diagnosis of RA.