AB0734 The Shades of Anti-JO1 Positive Antisynthetase Syndrome in a Hungarian Cohort

Background The most frequent myositis specific antibody (MSA) in the serum of patients with idiopathic inflammatory myopathies is anti-Jo-1. The presence of anti-Jo-1 define a distinct clinical phenotype, antisynthetase syndrome (ASS), which is characterized by poor prognosis and multiple organ involvement, such as myositis, interstitial lung disease (ILD), non-erosive arthritis, Raynaud9s phenomen, mechanic9s hand, skin rashes, and fever. Objectives The aim of this study was to determine the clinical, serological, laboratory and genetic features of anti-Jo1 positive patients followed by our department. Methods Retrospective analysis of medical records of 49 patients (42 female, 7 male) were reviewed. Anti-Jo-1 titer was detected with enzyme-linked immunosorbent assay. HLA DRB1, DQA1 and DQB1 genotype was determined using commercial sequence-specific oligonucleotide kit. Statistical analysis was performed using Pearson Chi 2 , Fisher exact test, or Spearman correlation. Results The median age at diagnosis was 43±13,28 years (range: 18-70), 48 patients exhibited myositis (98%), 35 ILD (73%), 43 arthritis (88%), 32 Raynaud9s phenomen (65%), 21 fever (43%), 16 mechanic9s hand (33%), 27 skin rash (55%) and 6 dysphagia (12%). We could detect significant correlation between the initial anti-Jo-1 titer and the first CK (R=0,328; p=0,003) and CRP (R=0,374; p=0,016) level. Furthermore anti-Jo1 levels during disease course had significant correlation to the corresponding CK (R=0,497; p Conclusions Our results confirm previously reported data from other centers considering the clinical features of anti-Jo1 positive patients. HLA DRB1*03 positivity was associated with lower CK level but has no influence on clinical or serological features. It seems that anti-Jo1 level might reflect disease activity; ESR, CRP levels, associated fever and anti-SSA positivity at the diagnosis could be considered as prognostic markers. Disclosure of Interest None declared