[Treatment of Dermatomyositis and Immune-Mediated Necrotizing Myopathy with Poor Muscle Recovery with Steroids and IVIg: Therapeutic Strategies for Refractory Inflammatory Myositis].

The majority of inflammatory myositis cases can be cured by immunomodulatory therapies. We recently observed that the phenotype and response to therapies differed according to myositis-specific autoantibodies; therefore, it is essential to select a suitable therapy after thoroughly evaluating the autoantibody, clinical severity, and complications. In some cases, the symptoms can be controlled by steroid monotherapy, but some cases exhibit steroid resistance and require other therapies. We recommend intensive treatment involving the addition of immunosuppressive agents in the early stage and repeated intravenous administration of immunoglobulin therapy in cases of refractory myositis, such as immune-mediated necrotizing myopathy.