LAUSR

We read an interesting study by Spielmann et al conducted on a single-centre large French cohort, which identified that anti-Ku autoantibodies were effective biomarkers for two distinct connective tissue diseases (CTDs): anti-Ku-positive patients with elevated serum creatine kinase (CK) levels had a high risk for developing interstitial lung diseases (ILD), while anti-Ku-positive patients with anti-double-strand DNA were at high risk for developing glomerulonephritis.1 Anti-Ku autoantibodies are associated with various CTDs, such as systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathies (IIM), mixed CTDs, Sjogren’s syndrome, and rheumatoid arthritis. However, few studies have focused on the distinguishing features, especially the pathological features of IIM patients with isolated anti-Ku and anti-Ku coexistence with myositis-specific autoantibodies (MSA). Here, we retrospectively investigated the characteristics of 1214 IIM patients with anti-Ku autoantibodies, all fulfilling the Bohan & Peter criteria for IIM and admitted to the Department of Rheumatology at China-Japan Friendship Hospital from January 2008 to July 2019. Anti-Ku autoantibodies were detected by line immunoassay (EUROLINE, Germany) and ELISA assay …