Introduction
Inflammatory myopathy, myositis, refers to a category of uncommon autoimmune disorders that entail chronic inflammation and muscular weakness and predominantly target the musculoskeletal system(1). The etiology of inflammatory myopathy remains elusive; however, it is postulated that a confluence of genetic susceptibility, environmental factors, and immune response dysregulation may contribute to its manifestation(2, 3).
There are mainly 4 types of inflammatory myopathy: dermatomyositis (DM), polymyositis (PM), overlap syndromes, and juvenile myositis(4).
The manifestation of DM is commonly observed through bilateral proximal skeletal muscle weakness, which is frequently accompanied by distinctive dermatological signs. A heliotrope flare-up localized on eyelids, Gottron’s papules, and periungual telangiectasia are the most prominent symptoms of DM(5). The Bohan and Peter criteria are frequently utilized in the diagnosis of dermatomyositis, incorporating a range of clinical, laboratory, electromyography, and muscle biopsy assessments(6).
PM is characterized by muscle inflammation without significant skin involvement(7). Overlap syndromes are characterized by the manifestation of features that are common to both inflammatory myopathy and an overlapping autoimmune disease. Organ involvement associated with systemic lupus erythematosus (SLE) and skin manifestations may be observed in patients(8).
Juvenile myositis encompasses inflammatory myopathies that occur in children. Juvenile myositis in children may demonstrate the same clinical presentations as adults, however, they may also manifest distinct characteristics, such as high skin involvement and a greater incidence of calcinosis(9).
Although the etiology of most cases of inflammatory myopathy remains unknown or is attributed to autoimmune factors, there have been limited reports of inflammatory myopathy presenting as an initial indication of an underlying tumor(10).