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Published on: September 30, 2021
Postpartum Acquired Hemophilia A
Khawaja O Omar1, William Sebastian2, Suzanne Kemper3
1Department of Internal Medicine - Division of Pulmonary Critical Care, Charleston Area Medical Center, Charleston, WV 25304, USA.
Abstract:
Acquired hemophilia A (AHA) is a bleeding disorder that occurs from aberrant production of autoantibodies that target factor VIII. The underlying cause of AHA is unclear but can present postpartum. Very few cases have reported instances of AHA coexisting with other hematological disorders, such as sickle cell trait (SCT). Although rare and no direct correlation between the two, critical situations involving intractable bleeding can intensify the severity of these disorders. A 31-year-old pregnant female with a medical history significant for SCT presented to the hospital for a C-section. Shortly after the procedure she experienced intractable bleeding from multiple sites. Initial lab work yielded an isolated increase in activated partial thromboplastin time (aPTT). Further investigation showed abnormal mixing studies, reduced factor VIII activity and the presence of factor VIII antibodies. The patient was diagnosed with postpartum AHA (PAH) and treated with activated Factor VII and prednisone. PAH is an uncommon bleeding disorder that commonly occurs one to four months postpartum and presents as excessive bleeding elevated aPTT, abnormal mixing studies, and reduced factor VIII levels with abnormally high inhibitor levels. Despite an unknown identifiable etiology, treatment hinges upon establishing hemostasis and eradicating the aberrant generated factor VIII inhibitors. The association of AHA and other hematological disorders is not yet elucidated.
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