Rev Med Interne 2020 Nov 25. Epub 2020 Nov 25.
Département de Médecine interne et immunologie clinique, Centre national de référence des maladies neuromusculaires, hôpital Pitié-Salpêtrière, AP-HP, 47-83, boulevard de l'Hôpital, 75651 Paris cedex 13, France.
Idiopathic inflammatory myopathies, or IIM, are a group of acquired diseases that affect the muscle to a certain extent, and may also affect other organs. They include dermatomyositis, which can affect the muscle eventualy, with a typical skin rash; inclusion body myositis, with a purely muscular expression resulting in a slow progressive deficit; and the former group of "polymyositis", a misnomer that actually includes other categories of IIM, such as immune-mediated necrotizing myopathies, with a severe muscle involvement often presents from the onset of the disease; antisynthetase syndrome, which combines muscle damage, joint involvement and a potentially life-threatening lung disease; and overlapping myositis, which combines muscle damage with other organs involvement connected to another autoimmune disease. The diagnosis of IIM is based on rigorous clinical examination and interrogation, electromyographic data and immunological testing for myositis specific antibodies. Read More