Management of acquired haemophilia A in severe Covid-19: Haemostatic bridging with emicizumab to keep the balance between bleeding and thrombosis.

Acquired haemophilia A (AHA) is an autoimmune bleeding disorder caused by autoantibodies blocking coagulation factor VIII (FVIII). Haemostatic management of AHA and concomitant thrombotic risk is difficult. We cover the management of a 75-year-old male with severe Covid-19, a prothrombotic disease, and de novo AHA with severe muscle bleeding, a disease requiring highly thrombogenic haemostatic therapy and immunosuppression-a challenging combination. FVIII activity was measured using human and bovine reagents to differentiate between endo- and exogenous FVIII activity. For haemostatic control, recombinant human activated FVII was given, followed by emicizumab, as a less thrombogenic long-term haemostatic agent. Steroids were used as initial immunosuppressive therapy. Later, rituximab was used for inhibitor eradication. No thromboembolic events occurred, and bleeding was effectively controlled. Emicizumab achieved haemostatic balance in a patient under haemorrhagic and thrombogenic conditions. Individual risk assessment is needed to guide treatment decisions in patients threatened by simultaneous bleeding and thrombosis.