A case of severe staphylococcal septicaemia: septic arthritis and a mediastinal abscess following leflunamide therapy for rheumatoid arthritis.

This highly unusual case illustrates how a potentially life-threatening complication may develop insidiously in the context of immunosuppression. A 46-year-old woman presented with increasing malaise and a marked inflammatory response in the context of immunosuppressive therapy for rhueumatoid arthritis. On the basis of microbiological findings, the patient was treated for systemic staphylococcal infection with a prolonged antibiotic course. In addition, incision and drainage procedures were performed on associated, non-resolving abscesses at various sites. One particular lesion in the breast was slow to heal and was monitored with ultrasound imaging. Subsequent cross-sectional imaging revealed that this was, in fact, a large mediastinal abscess, eroding the manubrium and lying within close proximity of the aorta. The patient was eventually referred to a cardiothoracic unit for complete evacuation of this lesion. Following a prolonged illness and treatment period, the patient recovered well and successfully resumed employment.