AB0743 The clinical manifestations in anti-ro52 antibody- positive patients with systemic sclerosis; a retrospective case control study

Background Autoantibodies (abs) directed against Ro52/TRIM21 are common in systemic sclerosis (SSc) but their clinical significance remains uncertain. Some reports suggested that anti-Ro52/TRIM21 abs-positive SSc patients present interstitial lung disorders (SSc-ILD). However, it is not clear whether positive for anti-Ro52/TRIM21 related to other clinical manifestations in patients with SSc. Objectives The aim of this study is to clarify the prevalence of anti-Ro52/TRIM21 abs in patients with SSc. Then, we investigated the clinical manifestations between anti-Ro52/TRIM2 abs-positive and negative patients with SSc. Methods This study is a retrospective case control study. The medical records of 42 patients who were diagnosed as having SSc admitted to our hospital were reviewed. We evaluated the clinical manifestations at the first-onset of SSc such as Rodnan skin score, digital ulcer, abnormal subcutaneous calcification, esophageal reflux, pulmonary hypertension, myositis and arthralgia. Co-existing rheumatic diseases were also reviewed such as Sjogren syndrome (SjS), rheumatoid arthritis (RA), and polymyositis. All subjects underwent SSc –associated abs testing using EUROLINE immunoblot assay. The autoantibodies include anti-Scl-70, anti-centromere A and B (CENP-A, CENP-B), anti-RNA polymerase III (RP-11, RP-155), anti-fibrillarin (U3RNP), anti- 90-kd nucleolar protein (NOR-90), anti-Th/To, anti-PM/Scl-100, anti-PM/Scl-75, anti-Ku, anti-platelet-derived growth factor receptor (PDGFR), and tripartite motif–containing protein 21(Ro-52). The association between clinical features and autoantibody profile was evaluated. Diagnosis of ILD was evaluated by chest high-resolution CT (HRCT). Results Thirty-five patients with SSc are female (87%). Twenty-one and nineteen patients with SSc are positive and negative for anti-Ro52/TRIM21 abs, respectively (47 v.s 52%). There is no difference in population of diffuse type of SSc between anti-Ro52/TRIM21 abs-positive and negative SSc patients. In addition, the prevalence of ILD is not different between two groups (57 v.s 52%, p=0.76). The prevalence of SjS is tended to be higher in anti-Ro52/TRIM21 abs-positive SSc patients than in negative SSc patients (68 v.s 33%, p=0.05). Unexpectedly, 57% of anti-Ro52/TRIM21 abs-negative SSc patients present poly-arthralgia at the onset of SSc. In addition, there were not any complications such as osteoarthritis and RA in anti-Ro52/TRIM21 abs-negative SSc patients. The prevalence of arthralgia was higher in anti-Ro52/TRIM21 abs-negative SSc patients than in positive SSc patients (p=0.02). Conclusions The prevalence of anti-Ro52/TRIM21 abs in SSc patients of this study seems to be high compared to other reports. In addition, there seems to be no difference in the prevalence of ILD regardless of existence of anti-Ro52/TRIM21 abs in SSc patients. Anti-Ro52/TRIM21 abs-negative SSc patients were tended to present poly-arthralgia. This musculoskeletal disorder of anti-Ro52/TRIM21 abs-negative SSc patients may be not associated with other rheumatic diseases such as SjS and RA in this study. It is necessary the large number study to clarify whether anti-Ro52/TRIM21 abs involve in the pathogenesis of musculoskeletal disorders in patients with SSc. Disclosure of Interest None declared