Bilateral thigh pyomyositis in an otherwise healthy middle-aged woman: A case report

BACKGROUND: Pyomyositis generally occurs in otherwise healthy young men. Because this condition is unusual among otherwise healthy women in temperate climates, we present the following case. CASE SUMMARY: An otherwise healthy 43-year-old woman presented with bilateral pain in her lower extremities and fever. Magnetic resonance imaging (MRI) findings were indicative of myositis with a possible abscess. We initiated empirical antibiotic therapy with ceftriaxone. However, the swelling and pain in her legs persisted even after 7 d of treatment. Contrast MRI revealed multiple pockets of pus in the vastus lateralis and gluteal muscles. We performed needle aspiration of these abscesses with ultrasound guidance and local anesthesia. Upon culturing, the purulent material was positive for Staphylococcus aureus. We diagnosed her with S. aureus-induced pyomyositis of the vastus lateralis muscle and gluteus region. Based on the antibiotic sensitivity report, ceftriaxone was administered for an additional 7 d. By day 15 post-drainage, the patient was able to start walking. Oral antibiotic therapy was continued for 1 wk following her discharge from hospital, after which her symptoms resolved completely. CONCLUSION: Pyomyositis may present with muscle pain, swelling, and fever. Ultrasound-guided percutaneous puncture and drainage may enable timely diagnosis and treatment.