Clinical significance of anti-Ro52 (TRIM21) antibodies in adult patients with connective tissue diseases

OBJECTIVES: Clinical significance of anti-Ro52 antibodies in connective tissue diseases (CTD) is controversial. Anti-Ro52 antibodies might be associated with a more severe CTD phenotype, especially interstitial lung disease (ILD). The aims of this study were to evaluate ILD prevalence and severity, the prevalence of micro- or macroangiopathy and CTD-associated cancers in CTD with anti-Ro52 antibodies. METHODS: CTD patients with anti-Ro52 antibody screening by immunoblot at diagnosis were enrolled. Two groups were retrospectively formed according to the presence of anti-Ro52 antibodies with an unbiased 1:1 matching on CTD types. Unsupervised multiple correspondence analysis and hierarchical clustering analysis were used to aggregate anti-Ro52 positive patients in subgroups. RESULTS: 408 CTD patients were included. Anti-Ro52 antibodies were detected in 33 % of CTD patients. Anti-Ro52 antibodies were associated with ILD at CTD diagnosis (47.8% vs. 23.0%, OR 3.3 95% IC 1.4 to 8.0, p = 0.008), even after adjusting for the presence of anti-Ro60 antibodies, especially in patients with antisynthetase syndrome, primary Sjögren syndrome and systemic sclerosis. Micro- or macroangiopathy was more frequent in anti-Ro52 positive CTD patients (18.6% vs. 9.7%, p = 0.02) and CTD patients with anti-Ro52 antibodies experienced more frequent relapses and required more immunosuppressive drugs. Clusters 4 and 5 identified anti-Ro52 positive CTD patients with severe ILD and with clinical features of systemic sclerosis or antisynthetase syndrome respectively. CONCLUSIONS: We found that anti-Ro52 antibodies were independently associated with ILD in CTD patients irrespective of CTD type. Anti-Ro52 antibodies could be associated with severity and a more relapsing disease course in CTD patients.