- Associated complications such as systemic diseases or auto-immune diseases (i.e. recurrent uveitis, cutaneous vasculitis, autoimmune hemolytic anemia, idiopathic thrombocytopenic purpura, rheumatoid arthritis resistant to steroids and/or immunomodulator agents (colchicin, disulone, hydrochloroquine)) and justifying a treatment with methotrexate or cyclophosphamide