Anti-aminoacyl-tRNA synthetase antibodies in clinical course prediction of interstitial lung disease complicated with idiopathic inflammatory myopathies

In the treatment of polymyositis and dermatomyositis (PM/DM), the complication of interstitial lung disease (ILD) is an important prognostic factor. It has been reported that autoantibodies against aminoacyl-tRNA synthetases (ARS) are strongly associated with ILD. The aim of this study is to examine the correlation between anti-ARS and the clinical course of ILD. We investigated 41 cases of PM/DM with ILD. The response of ILD to corticosteroids (CS) was determined according to the change in respiratory symptoms, image findings, and pulmonary function between, before and 2 months after the treatment. Anti-ARS (anti-Jo-1, PL-7, PL-12, EJ, OJ and KS) antibodies were screened with the RNA immunoprecipitation assay. In the stratification into ILD-preceding, simultaneous and myopathy-preceding types, anti-ARS antibodies were significantly frequent in the ILD-preceding type (p < 0.05). In the stratification into anti-ARS-positive and negative groups, the response of ILD to CS was significantly better in the posi...