Acquired Hemophilia A in Older Adults: A Case Series and Practical Diagnostic Approach

Abstract

Background: Acquired Hemophilia A (AHA) is a rare autoimmune bleeding disorder caused by autoantibodies against factor VIII (FVIII), with an incidence of 1–4 cases per million annually and a mortality rate exceeding 20%. It typically presents as spontaneous bleeding in individuals without personal or familial history of coagulation disorders.

Case Illustration: Three elderly patients (aged 52–75 years) with spontaneous bruising and no prior trauma, comorbidities, or bleeding history. They presented with isolated prolonged aPTT ranging from 69 to 78.8 seconds, severely reduced FVIII activity (1 IU/dL), and high-titer FVIII inhibitors between 35 and 213 Bethesda Units. All patients were treated with FVIII concentrate and corticosteroids.

Discussion: AHA results from immune-mediated inhibition of FVIII, leading to uncontrolled bleeding in soft tissues, muscles, and mucosa. Symptoms range from hematomas and ecchymosis to potentially fatal hemorrhages. Half of cases are idiopathic, while others are linked to underlying conditions.

Conclusion: Due to its rarity and diagnostic complexity, AHA requires high clinical suspicion and prompt management. Early recognition and targeted therapy are essential to control bleeding and eliminate inhibitors, improving patient outcomes. This study supports Sustainable Development Goal (SDG) 3 on Good Health and Well-being, particularly by promoting early diagnosis and effective management of rare autoimmune bleeding disorders to reduce morbidity and mortality.