Abstract
Pyomyositis is a rare condition in temperate climates. We present a case of Methicillin Resistant Staphylococcus aureus pyomyositis of the shoulder complicated by multifocal lung infiltrations, treated successfully with antibiotic therapy. After excluding shoulder septic arthritis, a low threshold of suspicion for the diagnosis of shoulder pyomyositis should be applied to patients with persistent fever, pain, and decreased range of shoulder motion. A prompt diagnosis and a rapid rise in antibiotic therapy are important to avoid local and systemic complications.