RESUMO
Pyomyositis is a purulent infection of skeletal muscle that is mostly observed in tropical countries. Aseptic pyomyositis is a rare, potentially life-threatening disorder characterized by the formation of sterile pus in muscle. We present a case of 53-years old female, diagnosed case of seropositive rheumatoid arthritis, presented with pain and swelling of the right calf muscle for 2 weeks. There was no history of fever, cough, skin erythema, no history of prolonged standing or immobility, or fetal loss. The diagnosis was made as rheumatoid arthritis with autoimmune pyomyositis, and the patient was treated with oral prednisolone 1mg/kg body weight in tapering dose, cs DMARDS, (methotrexate 25 mg once a week, and leflunomide 20mg daily hydroxychloroquine 200 mg daily orally) and another supportive treatment along with surgical drainage of pus was done. There was complete resolution of the initial lesion and remission of the primary disease in 3 months.