Case report: diabetes mellitus as a predisposing factor in the development of pyomyositis.

Pyomyositis is an uncommon infection in temperate climates, usually resulting from Staphylococcus aureus infection of skeletal muscle. In this report, the authors describe a patient with untreated Type 2 diabetes mellitus who suffered nonpenetrating blunt trauma to his left anterior thigh, and S. aureus pyomyositis and secondary osteomyelitis of his proximal tibia and patella subsequently developed as a result of delayed diagnosis and treatment. Patients with diabetes mellitus are at increased risk for the development of pyomyositis because of more frequent S. aureus colonization of skin, nasal mucosa, and oropharynx; a delay in definitive treatment can lead to significant morbidity in these patients. Computed tomography or magnetic resonance imaging may be helpful in the diagnosis of pyomyositis. An anemia of chronic disease may result from this disorder, which resolves with treatment.