Necrotizing fasciitis is a life-threatening soft tissue infection involving skin, subcutaneous tissue, and superficial fascia. We report a case of necrotizing fasciitis that developed in a 76- year-old female patient taking low-dose methotrexate and prednisolone for rheumatoid arthritis (RA). A computed tomography scan of the neck during the initial work-up showed soft tissue swelling, loss of fat planes, and mild heterogeneous enhancement in the right lateral neck, suggesting cellulitis. The lesions were associated with skin necrosis and multiple bullae rapidly expanded to the right anterior chest in spite of empirical antibiotic therapy. Surgical debridement was immediately performed, and soft tissue biopsy from the lesions showed the pathologic finding consistent with necrotizing fasciitis. The skin wound defect was reconstructed by a flap operation with split-thickness skin graft. This case shows the development of necrotizing fasciitis in a elderly patient taking methotrexate and low-dose steroid for RA and highlights early recognition and prompt surgical debridement for successful management.

Keywords: Rheumatoid arthritis, Necrotizing fasciitis, Methotrexate