Observations on the classification of the inflammatory myopathies

SummaryThis brief review considers historical approaches to the classification of the inflammatory myopathies. The last 25 years have seen advances in our knowledge of the underlying immune mechanism but the initial trigger for the idiopathic inflammatory myopathies remains unknown. Existing classifications have their limitations, but with the absence of a “gold standard” a definitive classification is not yet possible. Despite these problems, a working classification is possible that is valuable for everyday clinical practice.In this issueInflammatory or necrotizing myopathies, myositides and other acquired myopathies, new insight in 2011.O. Benveniste et al., Paris, FranceObservations on the classification of the inflammatory myopathiesD. Hilton-Jones, Oxford, United KingdomPathogenic aspects of dermatomyositis, polymyositis and overlap myositisR.K. Gherardi, Créteil, FranceSporadic inclusion-body myositis: conformational multifactorial aging-related degenerative muscle disease associated with proteasomal and lysosomal inhibition, endoplasmic reticulum stress, and accumulation of amyloid-β42 oligomers and phosphorylated tauV. Askanas et al., Los Angeles, USAPathophysiology of inflammatory and autoimmune myopathiesM.C. Dalakas, Philadelphia, USAMyositis or dystrophy? Traps and pitfallsO. Benveniste et al., Paris, FranceTherapy of polymyositis and dermatomyositisI. Marie, Rouen, France