Acquired hemophilia A
Other Names: Acquired factor 8 deficiency; Acquired factor VII deficiency
Acquired hemophilia A is a bleeding disorder that interferes with the body's blood clotting process. Although the condition can affect people of all ages, it generally occurs in older people (the median age of diagnosis is between 60 and 67 years).
Signs and symptoms
Signs and symptoms include prolonged bleeding, frequent nosebleeds, bruising throughout the body, solid swellings of congealed blood (hematomas), hematuria, and gastrointestinal or urologic bleeding.
Acquired hemophilia A occurs when the body's immune system attacks and disables a certain protein that helps the blood clot (called coagulation factor VIII). About half of the cases are associated with other conditions, such as pregnancy, autoimmune disease, cancer, skin diseases, or allergic reactions to medications.
Treatment is aimed at controlling bleeding episodes and addressing the underlying cause of the condition.
Patients with acquired coagulation factor inhibitors should be treated jointly with haemophilia centres experienced in the management of inhibitors. Initial treatment consists of four steps:
- Prevention of bleeding events, avoiding or minimizing actions that might provoke bleeding such as intramuscular injections, invasive procedures and use of antiplatelet and nonsteroidal anti-inflammatory agents.
- Treatment of the underlying disorder.
- Therapy of bleeding
- Antibody eradication
Therapy of bleeding
Anti-haemorrhagic treatment should be initiated in patients with AHA and active severe bleeding symptoms irrespective of inhibitor titre and residual FVIII activity. First-line treatment includes by-pass agents (activated prothrombin complex concentrates [aPCC] Factor Eight Inhibitor Bypassing Activity [FEIBA] and recombinant activated factor VII [[[rFVIIa]]]). Both treatments are effective and there is no evidence for the use of one product in preference to the other. Therapy should be continued until bleeding is controlled and management must generally rely on the clinical assessment as there are no validated laboratory tests to determine therapeutic levels. The main concern about the use of these agents is the appearance of thrombotic events
A recombinant porcine FVIII molecule has recently been approved to treat bleeding episodes, with similar pharmacokinetics to human FVIII and the possibility of laboratory measurement and dose-adjustment
All patients diagnosed with AHA should receive immunosuppressive therapy immediately following diagnosis with prednisolone either alone or combined with cyclophosphamide, what has a complete remission rate of 70-80%.
If there is no response within 3–5 weeks, second-line therapies should be considered. The most common second-line treatment is with rituximab combined with other agents. Alternative options are calcineurin inhibitors, multiple immunosuppressive agents and immune tolerance protocols.
Most immunosuppressive drugs are associated with side effects, including neutropenia-related infections and sepsis.
The relapse rate after a first complete remission has been estimated at about 20%
The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition.
Antihemophilic factor (recombinant), Fc fusion protein (Brand name: Eloctate) antihemophilic factor (recombinant), Fc fusion protein (Eloctate) was approved for the treatment of adults and children with Hemophilia A (congenital Factor VIII deficiency) for control and prevention of bleeding episodes, perioperative management, and routine prophylaxis to prevent or reduce the frequency of bleeding episodes.