[An immunocompromised man with a fever]

Area of Science:

• Infectious Diseases
• Oncology
• Rheumatology

Background:

• Prolonged use of corticosteroids, such as dexamethasone, is common in managing various conditions, including recurrent plasmacytoma.
• Immunosuppression secondary to corticosteroid therapy can increase the risk of opportunistic infections.

Observation:

• A 42-year-old male patient with a history of recurrent plasmacytoma on long-term dexamethasone presented with fever.
• The patient exhibited tender, red swelling in his right upper leg and arm, indicative of localized inflammation.

Findings:

• Diagnostic evaluation revealed pyomysitis, a deep muscle infection characterized by pus formation.
• Cultures identified Staphylococcus aureus as the causative pathogen responsible for the pyomysitis.

Implications:

• This case underscores the importance of considering pyomysitis in immunocompromised patients presenting with localized swelling and fever.
• Prompt diagnosis and appropriate antibiotic treatment targeting Staphylococcus aureus are crucial for managing pyomysitis in patients on immunosuppressive therapy.