Necrotizing fasciitis in a rheumatoid arthritis patient treated with tocilizumab

Sir, Necrotizing fasciitis (NF) is a severe infectious disease affecting the subcutaneous tissue associated with considerable mortality (70–80%). Tocilizumab is a humanized anti-IL-6 receptor antibody that has recently been approved for the treatment of RA and other inflammatory joint diseases. The most important serious adverse events (SAEs) reported during treatment with tocilizumab are infectious complications [1, 2]. A 59-year-old woman presented at the emergency room with severe pain in the right axillary line just next to her right breast of 6 h duration without any other complaints. She denied recent trauma. Her past medical history mentioned Hashimoto's hypothyroidism, cerebrovascular ischaemia, and since 2009 she has been treated for IgM RF, anti-citrullinated protein-positive RA. Previously she was treated with MTX, HCQ, adalimumab and etanercept, which were discontinued because of lack of efficacy. Two months before presentation she was started on tocilizumab monotherapy (800 mg i.v. every 4 weeks). She did not have CS as a background therapy.