Outcome of acquired haemophilia in France: the prospective SACHA (Surveillance des Auto antiCorps au cours de l'Hemophilie Acquise) registry

Although extremely rare, acquired haemophilia A (AHA) can cause severe bleeding, which may be fatal. The underlying causes of autoantibody development are not fully understood. Treatment goals are bleeding control and autoantibody eradication. At the time of our study, there was no consensus on a standard treatment strategy for AHA. Previous data were mainly retrospective or from single-centre cohorts. We conducted a prospective, controlled, registry-based study of patients with AHA in France. The prospective French registry (Surveillance des Auto antiCorps au cours de l'Hemophilie Acquise [SACHA]) collected data on prevalence, clinical course, disease associations and outcomes for haemostatic treatment and autoantibody eradication in 82 patients with a 1-year follow-up. Similar to earlier studies, the prevalence of AHA was higher in the elderly, with two thirds of patients aged >70years. Around half of AHA cases were associated with underlying disease, most commonly autoimmune disease and cancer in younger and older patients respectively. Haemostatic treatment was initially administered to 46% of patients. Complete resolution or improvement of initial bleeding occurred in 22/27 (81%) rFVIIa-treated patients and in all six cases receiving pd-aPCC. The majority of patients (94%) received immunosuppressive therapy, with complete remission at 3months in 61% (36/59) and in 98% (50/51) at 1year. Overall mortality was 33%: secondary to bleeding in only three patients but to sepsis in 10. Bypassing agents were effective at controlling bleeding in patients with AHA. Immunosuppressive therapy should be used early but with caution, particularly in elderly patients.