DOI: https://doi.org/10.36347/sjmcr.2026.v14i08.005

Pages: 1774-1778

Introduction: Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder caused by the development of inhibitory autoantibodies directed against coagulation factor VIII (FVIII). It may occur in association with various underlying conditions, including autoimmune diseases, malignancies, pregnancy, and drugs. However, its association with autoimmune bullous dermatosis remains exceptional. Case report: We report the case of a 60-year-old woman with a history of longstanding psoriasis and autoimmune bullous dermatosis, who developed severe bleeding manifestations. Laboratory investigations revealed an isolated prolongation of activated partial thromboplastin time (aPTT) and a high-titer FVIII inhibitor (748 Bethesda units/mL). Reduced activities of intrinsic pathway coagulation factors (FVIII, FIX, FXI, and FXII) were observed, likely related to analytical interference of one-stage clotting assays in the presence of a high-titer FVIII inhibitor. Immunological evaluation showed persistent triple positivity for antiphospholipid antibodies without clinical criteria for antiphospholipid syndrome. After initial treatment with corticosteroids combined with cyclophosphamide, followed by rituximab and maintenance therapy with mycophenolate mofetil, an initial decrease in inhibitor level was achieved, followed by secondary re-elevation without recurrence of bleeding manifestations. Conclusion: This observation highlights the complexity of AHA associated with autoimmune bullous dermatosis, characterized by challenges in laboratory interpretation and a prolonged discrepancy between FVIII inhibitor levels and clinical evolution. Clinical assessment should remain central to therapeutic decision-making, beyond isolated biological parameters.