Critical role of laboratory and multidisciplinary strategies in the early diagnosis of acquired haemophilia a for life-saving management

Background: Acquired haemophilia A (AHA) is a rare but potentially life-threatening autoimmune disorder characterized by the development of autoantibodies against coagulation factor VIII (FVIII). It manifests with spontaneous, severe bleeding in patients without a personal or family history of bleeding disorders. Early recognition and rapid treatment are crucial to reduce morbidity and mortality. Case presentation: Here we describe two cases of AHA in elderly female patients with no prior history of coagulopathy. The first case involved an 81-year-old woman presenting with extensive spontaneous haematomas and severe anaemia. Laboratory findings revealed an isolated prolonged activated partial thromboplastin time (aPTT), undetectable FVIII activity, and the presence of a low-titre FVIII inhibitor (2.24 BU/mL). Treatment with recombinant activated factor VII (rFVIIa) and corticosteroids led to clinical improvement and inhibitor reduction. The second case concerned an 85-year-old woman who developed severe haemorrhagic manifestations following ureteric stenting. Coagulation studies showed markedly prolonged aPTT and a high-titre FVIII inhibitor (165 BU/mL). Despite initiation of immunosuppressive therapy the patient experienced fatal complications due to uncontrolled bleeding and multi-organ failure. Conclusions: These cases underscore the importance of considering a possible AHA in patients with isolated aPTT prolongation and unexplained bleeding. Punctual laboratory diagnosis, including mixing studies and FVIII inhibitor assays, is essential for early life-saving interventions. Multi-disciplinary management and rapid initiation of haemostatic and immunosuppressive therapies are key to improving outcomes in this challenging condition.