Development of necrotising fasciitis in a patient treated for rheumatoid arthritis with tocilizumab.

Necrotising fasciitis (NF) is a potentially lethal infection affecting subcutaneous tissue and superficial fascia that may progress to multiple organ failure, and the prognosis is often worse when the host is immunocompromised. The prognosis is influenced by early diagnosis and early surgical debridement (1). Biologic therapies have been used in treating intractable inflammatory diseases, including collagen disorders. When using such a treatment strategy, it is critical to be aware that the treated subject may be highly susceptible to infection. Tocilizumab is a humanised monoclonal antibody directed against the interleukin-6 (IL-6) receptor and is recognised as an excellent biologic treatment in inflammatory rheumatic conditions (2). However, we wish to highlight the fact that its use may be associated with serious adverse reactions such as NF. It is known that tocilizumab may completely suppress induced C-reactive protein (CRP) via neutralisation of IL-6 effects (3). In fact, there have been a few reports of infections and other adverse events in subjects treated with tocilizumab (4). CASE REPORT