Posted by New Delhi:Haemophilia is recognised as the most common and severe haemorrhagic disorder. Depending upon the pathophysiology, there are three types of haemophilia -A, B, and C, caused by the deficiency or dysfunction of factors VIII, IX, and XI, respectively. It can be hereditary, which is more common, and a rare variety is the acquired one. Acquired haemophilia is due to the autoantibodies that develop against a coagulation factor. Mostly the antibodies develop against factor VIII, hence commonly known as “acquired haemophilia A” (AHA).
Dr Mahadeva Swamy, Consultant – Haemato Oncologist and Bone Marrow transplant physician, Manipal Hospital Goa, said, “AHA is an uncommon but severe bleeding disorder. It is caused by the development of autoantibodies directed against one of the haemophilic factors, most frequently factor VIII (FVIII). The diagnosis of this disease is established with difficulty because of its rarity and the complexity of the laboratory diagnosis. It must be diagnosed and treated promptly to avoid the high morbidity and mortality associated with this condition.”
Clinically, the presentation varies from life-threatening bleeds on one end to mild or no bleeds on the other end. The presentation with life-threatening bleeding is usually seen during the initial several weeks, although it can happen at any point during the disease if the appropriate treatment is not initiated.
Treatment for acquired haemophilia
The recommendations usually rely on the clinical judgment and expertise of the providers who have treated patients with AHA. The reason is the unavailability of an international consensus for management.
The management of AHA, however, comprises of a two-pronged therapy approach in which both modalities go hand in hand. These are:- Haemostasis management & Eradication of Inhibitor.
Haemostasis management: First-line treatment is the use of bypassing agents. The bypassing agents are named so because of their mechanism of action. They act by bypassing the need for factor VIII in the coagulation pathway in the production of thrombin. These agents include activated prothrombin complex concentrate (PCC) and recombinant activated Factor VII (FVIIa). The prothrombin complex concentrate is plasma-derived and contains exogenously activated vitamin K-dependent factors (factors II, VII, IX, X).
Eradication of Inhibitor: The treatment of AHA depends on correcting the pathophysiology that arises due to the presence of factor autoantibody. In the presence of the autoantibody, the patient is always at risk of life-threatening bleeding, and the complete eradication of the inhibitor is vital for improving survival in patients.
Inhibitor eradication therapy should be initiated along with haemostatic therapy as the delay has been associated with poor patient outcomes. For this purpose, the first-line treatment includes prednisone (1 mg/kg/day). It can be used alone or cyclophosphamide (50 to 100 mg/day) can be added, although evidence suggests that the combined use is correlated with better patient outcomes.