Acquired hemophilia A.

Acquired hemophilia A is a rare, autoimmune disorder that is caused by autoantibodies that act as inhibitors to factor VIII. It is characterized by severe, unexpected bleeding that may be life-threatening. The incidence of acquired hemophilia A is ~ 0.2 to 1.48 cases per 1 million individuals per year. Acquired hemophilia A has been associated with several clinical conditions including pregnancy, autoimmune or collagen vascular disorders, malignancies, drugs, respiratory disorders, and infections. However, in ~ 50% of cases, no disease association is determined. Acquired hemophilia A should be suspected when a patient with no previous personal or family history of bleeding, presents with bleeding and an unexplained prolonged activated partial thromboplastin time (APTT) and other common causes of a prolonged APTT are ruled out. The treatment of acquired hemophilia A has two main goals: (1) to treat and/or prevent bleeding complications and (2) to eradicate the inhibitor. The recommended agents to be used for the treatment or prevention of bleeding in patients with acquired hemophilia A are the bypassing agents. Patients should be treated initially with corticosteroids, either alone or in combination with cyclophosphamide, to eradicate the inhibitor. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.