Acquired Haemophilia Associated with Urticarial Vasculitis

Acquired haemophilia (AHA) is a rare autoimmune disorder caused by circulating autoantibodies that inhibit the activity of factor VIII (FVIII). Acquired inhibitors against FVIII are rarely seen, with a reported incidence of approximately 1 case per million/year. Clinical conditions and contexts associated with AHA include autoimmune diseases, lymphoproliferative malignancies, drug treatment, pregnancy and infections. An association with urticarial vasculitis is even more rare. Here, we report a case of a 59-year-old woman presenting with cutaneous and muscle haematomas secondary to AHA in association with urticarial vasculitis, who was successfully treated with factor eight inhibitor bypassing activity (FEIBA) and prednisolone. LEARNING POINTS: Acquired haemophilia (AHA) is a rare autoimmune disease. AHA predisposes to severe, potentially life-threatening haemorrhage. An association with urticarial vasculitis is even more rare.