Hemophilia is a congenital bleeding disorder that results in the blood failing to clot normally. It is caused by a deficiency of a protein in the blood called a clotting factor. People with hemophilia bleed easily and often excessively. Untreated, hemophilia can be life-threatening. There are two types of hemophilia: “Hemophilia A” is the most common type and is caused by the deficiency of what is known as Clotting Factor VIII; “hemophilia B” is caused by deficiency of Clotting Factor IX.
Hemophilia occurs in about 1 in 10,000 births and it is much more common in males because it is an “X-linked” disorder. The number of affected persons worldwide is estimated to be about 400,000. Hemophilia A is more common than hemophilia B, representing 80-85% of all cases.
Hemophilia should be suspected in patients presenting with a history of:
- Easy bruising in early childhood.
- Spontaneous bleeding (bleeding for no apparent/known reason), especially into the joints, muscles, and soft tissues.
- Excessive bleeding following trauma or surgery.
A definitive diagnosis depends on a blood analysis to determine deficiency of Clotting Factor VIII or IX. Because each type of hemophilia requires a different therapy, accurate diagnosis is essential.
Hemophilia can be very successfully managed by simply replacing the deficient clotting factor. Therapy can be either “on demand” - the treatment of active bleeding, or “prophylactic” - regular maintenance of clotting factor levels to prevent bleeding. In developed countries where these factors are readily available, the life expectancy of males suffering from hemophilia is essentially the same as for males in the general population.
Both clotting factors can be isolated from donated human plasma and they can also be engineered by means of recombinant DNA technology. There are many commercial brands from which to choose and that choice is generally made based on price and on the risk of developing antibodies that render the factor ineffective.
1.Srivastava a. et al. Guidelines for the management of Hemophilia. Haemophilia (2012), 1–47.
2. Mannucci PM et al. How we choose factor VIII to treat Hemophilia. Blood (2012) volume 119, number 18, 4108-4114.