PO131 | BEYOND THE INHIBITOR TITER: THE IMPORTANCE OF EARLY COMBINED IMMUNOSUPPRESSIVE THERAPY IN THE MANAGEMENT OF ACQUIRED HEMOPHILIA A
Abstract
Background. Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder caused by factor VIII (FVIII) inhibitors, typically characterized by an isolated prolongation of activated partial thromboplastin time (aPTT). Current evidence suggests that bleeding severity does not strictly correlate with inhibitor titers, which may lead to an underestimation of clinical severity. Case Report. We report the case of an 80-year-old woman with a history of hypertension, dyslipidemia, and a biological prosthetic valve on antiplatelet therapy, who was admitted to the Emergency Department with diffuse spontaneous ecchymoses. Laboratory evaluation showed a prolonged aPTT (89.1 s), a normal prothrombin time (PT), a hemoglobin level of 10.3 g/dL, a non-corrective mixing test, FVIII activity of 0.8%, and the presence of a low-titer anti-FVIII inhibitor (2.39 BU). Despite the low inhibitor titer and the absence of major bleeding, the patient exhibited extensive mucocutaneous hemorrhagic manifestations and very low residual FVIII levels (<1%). After secondary causes were excluded, a diagnosis of idiopathic AHA was made. In accordance with current clinical guidelines, combined therapy with recombinant activated factor VII (rFVIIa), corticosteroids, cyclophosphamide, and tranexamic acid was promptly initiated. The patient showed rapid clinical and laboratory improvement, with normalization of FVIII levels (83%), eradication of the inhibitor, and stabilization of hemoglobin levels. A biochemical relapse (FVIII 24%, inhibitor 2.2 BU) during follow-up was effectively treated with the same immunosuppressive regimen, achieving a new remission. Conclusions. This case report highlights that inhibitor titers can be misleading in AHA. Consistent with current recommendations, therapeutic decisions should be guided primarily by the clinical presentation. An early combined immunosuppressive approach, in the absence of contraindications, can lead to rapid and sustained remission even in frail patients, although careful follow-up is required due to the risk of relapse and treatment-related complications. Clinical suspicion, based on isolated prolongation of aPTT, remains crucial for timely diagnosis and management.
Related
- Clinical and endoscopic features of checkpoint inhibitor–induced colitis and their association with selective immunosuppressive therapy use
- RECOMBINANT FACTOR VIII, FAMILY HISTORY, AND HIGH-TITER INHIBITOR RISK IN SEVERE HEMOPHILIA A
- PO127 | ANAPHYLACTIC REACTION TO RECOMBINANT ACTIVATED FVII IN A MILD HEMOPHILIA A PATIENT WITH INHIBITOR: A CASE REPORT
- Postpartum Stroke: The Importance of Early Recognition and Multidisciplinary Management
- PO024 | IMPLEMENTATION OF 4PL SIGMOIDAL REGRESSION FOR FACTOR VIII INHIBITOR QUANTIFICATION IN ACQUIRED HEMOPHILIA
BibTeX
@article{luongo2026po131,
title = {{PO131 | BEYOND THE INHIBITOR TITER: THE IMPORTANCE OF EARLY COMBINED IMMUNOSUPPRESSIVE THERAPY IN THE MANAGEMENT OF ACQUIRED HEMOPHILIA A}},
author = {Myriam Luongo},
journal = {Bleeding, Thrombosis and Vascular Biology},
year = {2026},
month = oct,
url = {https://www.btvb.org/btvb/article/view/947},
note = {CC BY-NC},
}
RIS
TY - JOUR
TI - PO131 | BEYOND THE INHIBITOR TITER: THE IMPORTANCE OF EARLY COMBINED IMMUNOSUPPRESSIVE THERAPY IN THE MANAGEMENT OF ACQUIRED HEMOPHILIA A
AU - Myriam Luongo
PY - 2026
DA - 2026/10/26
JO - Bleeding, Thrombosis and Vascular Biology
UR - https://www.btvb.org/btvb/article/view/947
AB - Background. Acquired hemophilia A (AHA) is a rare autoimmune bleeding disorder caused by factor VIII (FVIII) inhibitors, typically characterized by an isolated prolongation of activated partial thromboplastin time (aPTT). Current evidence suggests that bleeding severity does not strictly correlate with inhibitor titers, which may lead to an underestimation of clinical severity. Case Report. We report the case of an 80-year-old woman with a history of hypertension, dyslipidemia, and a biological prosthetic valve on antiplatelet therapy, who was admitted to the Emergency Department with diffuse spontaneous ecchymoses. Laboratory evaluation showed a prolonged aPTT (89.1 s), a normal prothrombin time (PT), a hemoglobin level of 10.3 g/dL, a non-corrective mixing test, FVIII activity of 0.8%, and the presence of a low-titer anti-FVIII inhibitor (2.39 BU). Despite the low inhibitor titer and the absence of major bleeding, the patient exhibited extensive mucocutaneous hemorrhagic manifestations and very low residual FVIII levels (<1%). After secondary causes were excluded, a diagnosis of idiopathic AHA was made. In accordance with current clinical guidelines, combined therapy with recombinant activated factor VII (rFVIIa), corticosteroids, cyclophosphamide, and tranexamic acid was promptly initiated. The patient showed rapid clinical and laboratory improvement, with normalization of FVIII levels (83%), eradication of the inhibitor, and stabilization of hemoglobin levels. A biochemical relapse (FVIII 24%, inhibitor 2.2 BU) during follow-up was effectively treated with the same immunosuppressive regimen, achieving a new remission. Conclusions. This case report highlights that inhibitor titers can be misleading in AHA. Consistent with current recommendations, therapeutic decisions should be guided primarily by the clinical presentation. An early combined immunosuppressive approach, in the absence of contraindications, can lead to rapid and sustained remission even in frail patients, although careful follow-up is required due to the risk of relapse and treatment-related complications. Clinical suspicion, based on isolated prolongation of aPTT, remains crucial for timely diagnosis and management.
SN - 2785-5309
ER -