Inflammatory Myopathies

Inflammatory myopathies represent a small but important group of acquired muscular disorders. The most important forms of immunogenic inflammatory myopathies are dermatomyositis (DM), polymyositis (PM) and inclusion body myositis (IBM). A hallmark of all types of immunogenic inflammatory myopathies is infiltration (B-cells, CD4+ and CD8+ T cells and macrophages) in muscle tissue. In DM, inflammatory infiltrates with B-cells and CD4+ T cells are found predominantly in perivascular and perifascicular regions, producing the picture of a myositis of the perifascicular type. There are striking lesions of the small in…