PolymyositisDermatomyositisMyositisHistidine-tRNA LigaseLung Diseases, InterstitialMyositis, Inclusion BodyPrednisoloneMuscular DiseasesAutoantibodiesParaneoplastic SyndromesCreatine KinaseMusclesScleroderma, SystemicConnective Tissue DiseasesMuscle, SkeletalMyoglobinuriaNervous System Autoimmune Disease, ExperimentalAutoimmune DiseasesAntibodies, AntinuclearMediastinal EmphysemaMuscle WeaknessMuscular DystrophiesImmunosuppressive AgentsBiopsyMixed Connective Tissue DiseaseFatal OutcomeAdrenal Cortex Hormones