Revised Classification for Idiopathic Inflammatory Myopathies

Four subgroups emerge based on clinical, serologic, and pathologic data: dermatomyositis, inclusion body myositis, immune-mediated necrotizing myopathy, and antisynthetase syndrome.

Idiopathic inflammatory myopathies (IIM) are heterogeneous disorders characterized by muscle weakness and inflammation and historically classified as dermatomyositis (DM), polymyositis (PM), or inclusion body myositis (IBM). More recently, important and separate entities with muscle-specific autoantibodies have been identified. Researchers aimed to more precisely identify subgroups of IIM based on a French myositis registry.

Using multiple correspondence analysis and hierarchical cluster analysis, the investigators identified four clusters in a cohort of 260 adults diagnosed with myositis. Most patients in cluster 1 (94%) had IBM and had finger flexor weakness, vacuolated fibers, and mitochondrial abnormalities. Cluster 2 corresponded to imm…

Reviewing Author

Leana Doherty, MD

Disclosures

Editorial BoardsNeurohospitalist Society; InterACTN (Annals of Clinical and Translational Neurology)

Leana Doherty, MD

Disclosures

Editorial BoardsNeurohospitalist Society; InterACTN (Annals of Clinical and Translational Neurology)

Revised Classification for Idiopathic Inflammatory Myopathies

Topics

Reviewing Author