The use of tocilizumab in the treatment of refractory eosinophilic fasciitis: a case-based review.

Eosinophilic fasciitis (EF) is a rare disorder involving chronic inflammation of the fascia and connective tissue of unknown aetiology and poorly understood pathogenesis. We present the case of a 60-year-old man diagnosed with eosinophilic fasciitis with extensive cutaneous involvement and severe functional repercussion, which appeared weeks after suffering from pneumonia due to Legionella pneumophila. The patient did not experience any clinical response with high-dose corticosteroids, subcutaneous methotrexate, and intravenous immunoglobulins. Consequently, tocilizumab was initiated at 8 mg/Kg monthly achieving clinical response measured by a control MRI at the fifth dose. Response in terms of cutaneous thickness has been slower however favourable, therefore, more months of follow-up are necessary to assess the complete remission at skin level. EF treatment still constitutes a challenge, and experience with tocilizumab in the management of the disease is very limited. Through a systematic search of medical literature, we retrieved two cases describing EF treated with tocilizumab and several cases using another monoclonal antibody or Janus kinase inhibitor. We report the third case to our knowledge of the efficacy of tocilizumab in a refractory EF to corticosteroids and other immunosuppressive drugs.