What is Haemophilia A?
Haemophilia A is a rare type (1:6.000) of bleeding disorder that occurs if a deficiency or absence of a clotting factor (Factor VIII) exists. As a result, a person with haemophilia A will experience longer bleeding after injury, as the blood clot formed is not strong enough to stop bleeding.
What is clotting factor? What does it do?
Clotting factors are proteins in the blood that control bleeding. After injury of a blood vessel, it first contracts to reduce the blood flow. Then tiny cells of the blood so called platelets stick together at the injury site. A signal cascade activates the platelets and more cells stick to the platelet plug, the platelet plug is stabilized by thread-like strands called fibrin that interacts with itself and then forms a fibrin net. The fibrin net entraps the platelet plug and through a series of chemical reactions and interactions of the clotting factors a blood clot develops. The clot acts like a mesh to stop bleeding. There are thirteen clotting factors working in sequence and their interactions are part of a process known as the coagulation cascade. The clotting factors are identified with Roman numerals.
What are the causes of haemophilia A?
Haemophilia A is an inherited disease, meaning that the un-functional gene responsible for causing haemophilia is passed from parent to a child. The type of clotting factor that is missing determines what type of haemophilia you have. The most common types are haemophilia A and B. In haemophilia A the clotting factor missing is Factor VIII and in haemophilia B it is Factor IX.
What’s the difference between mild, moderate and severe Haemophilia?
The severity describes how serious the disease is and is related to the level of clotting factor that is missing from the patients’ blood.
Mild hemophilia patients have Factor VIII levels 6% to 49% of normal.
People with mild hemophilia (15-31%) usually bleed as a result of surgery or major injury. They do not bleed often and, in fact, some may never have a bleeding problem.
Moderate hemophilia patients have Factor VIII levels 1% to 5% of normal.
People with moderate hemophilia (15-26%) bleed less frequently, about once a month. They may bleed for a long time after surgery, a bad injury, or dental work. A person with moderate hemophilia will rarely experience spontaneous bleeding.
Severe hemophilia patients have Factor VIII levels of < 1% of normal.
People with severe hemophilia (43-70%) usually bleed frequently into their muscles or joints. They may bleed one to two times per week. Bleeding is often spontaneous, which means it happens for no obvious reason.
Reference: World Federation of Hemophilia
How can Haemophilia A currently be treated?
There is presently no cure for haemophilia, but treatment works by replacing the missing or non-functioning clotting factor. Haemophilia A is treated by three weekly infusions of the missing Factor VIII into the affected person’s vein. The injection makes the Factor VIII immediately available in the bloodstream and the body is able to activate it to continue the clotting cascade and stop the bleeding. Annual costs for the treatment of the disease for each patient may range from 60.000 € to 260.000 €.