Observations on the classification of the inflammatory myopathies

This 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 issue Inflammatory or necrotizing myopathies, myositides and other acquired myopathies, new insight in 2011. O. Benveniste et al., Paris, France Observations on the classification of the inflammatory myopathies D. Hilton-Jones, Oxford, United Kingdom Pathogenic aspects of dermatomyositis, polymyositis and overlap myositis R.K. Gherardi, Créteil, France Sporadic 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 tau V. Askanas et al., Los Angeles, USA Pathophysiology of inflammatory and autoimmune myopathies M.C. Dalakas, Philadelphia, USA Myositis or dystrophy? Traps and pitfalls O. Benveniste et al., Paris, France Therapy of polymyositis and dermatomyositis I.