Microorganisms in Pathogenesis and Management of Dermatomyositis (DM) and Polymyositis (PM)

As with most autoimmune diseases, the etiology and especially the prime mover of idiopathic inflammatory myopathies are not well defined. It is assumed that the disease is related to a chronic immune impairment, following exposure to environmental agents in genetically predisposed individuals. In this chapter we discuss the role of microorganisms in pathogenesis of myopathies, especially polymyositis and dermatomyositis. We focused on interaction between immune response and biological and molecular networks created by host characteristics and most common pathogens as described in the literature on the topic. Infectious agents proved a strong connection with autoimmune myositis in several animal models, and, learning from the infamous recent zoonosis which started the SARS-CoV-2 (“the autoimmune virus”) pandemic, new challenges and discoveries are around the corner.