Pyomyositis is a pyogenic infection of skeletal muscle that arises from hematogenous spreadand usually presents with localized abscess. This muscle infection has been rarely reportedin adult-onset systemic lupus erythematous and, to the best of our knowledge, has not beendiagnosed in pediatric lupus population. Among our childhood-onset systemic lupus erythematous population, including 289 patients, one presented pyomyositis. This patient wasdiagnosed with childhood-onset systemic lupus erythematous at the age of 10 years-old. After six years, while being treated with prednisone, azathioprine and hydroxychloroquine,she was hospitalized due to a 30-day history of insidious pain in the left thigh and no apparent trauma or fever were reported. Her physical examination showed muscle tendernessand woody induration. Laboratory tests revealed anemia, increased acute phase reactantsand normal muscle enzymes. Computer tomography of the left thigh showed collectionon the middle third of the vastus intermedius, suggesting purulent stage of pyomyositis. Treatment with broad-spectrum antibiotic was initiated, leading to a complete clinicalresolution. In conclusion, we described the first case of pyomyositis during childhood inpediatric lupus population. This report reinforces that the presence of localized musclepain in immunocompromised patients, even without elevation of muscle enzymes, shouldraise the suspicion of pyomyositis. A prompt antibiotic therapy is strongly recommended.
Blay, G., Ferriani, M. P. L., Buscatti, I. M., França, C. M. P., Campos, L. M. A., & Silva, C. A. (2016). Pyomyositis in childhood-systemic lupus erythematosus. Revista Brasileira de Reumatologia, 56(1), 79–81. https://doi.org/10.1016/j.rbre.2014.04.005