How Hemophilia is Treated
Hemophilia is treated by replacing the missing clotting factor in the blood. This is done by injecting a product that contains the needed factor into a vein. Bleeding stops when enough clotting factor reaches the bleeding site. It is very important that treatment is given as quickly as possible to prevent long-term damage.
With an adequate quantity of treatment products and proper care, people with hemophilia can live perfectly healthy lives.
Clotting factors are found in the following blood products in order of decreasing concentration:
- factor concentrates
- whole blood
Factor concentrates are the treatment of choice for hemophilia. They can be made from human blood (called plasma-derived products) or manufactured using genetically engineered cells that carry a human factor gene (called recombinant products). Factor concentrates are made in sophisticated manufacturing facilities. All commercially prepared factor concentrates are treated to remove or inactivate blood-borne viruses.
People with mild hemophilia A sometimes use desmopressin (also called DDAVP), a synthetic hormone that stimulates the release of factor VIII.
Cryoprecipitate is derived from blood and contains a moderately high concentration of factor VIII (but not IX) clotting factor. It is effective for joint and muscle bleeds, but is less safe from viral contamination than concentrates and is harder to store and administer. Cryoprecipitate can be made at local blood collection facilities.
In fresh plasma the red cells have been removed, leaving the blood proteins including the clotting factors. It is less effective than cryoprecipitate for the treatment of hemophilia A because the factor VIII is less concentrated. Large volumes of plasma must be transfused. This can cause circulatory overload.
The life of the clotting factors is preserved by making a product called fresh frozen plasma (FFP). FFP is still the only product available for treatment of hemophilia A and B in some countries.
There are considerable drawbacks to the use of whole blood in the treatment of hemophilia. First, it must be fresh because the activity of the clotting factors in the drawn blood decreases quickly with time. Second, the red cells it contains must, of course, be compatible with those of the recipient. Third, it takes a large volume of whole blood to stop a bleed and this volume may overload the circulation and cause the heart to fail.
Antifibrinolytic medicines (including tranexamic acid and aminocaproic acid) may be used with replacement therapy. They’re usually given as a pill, and they help keep blood clots from breaking down.
These medicines most often are used before dental work or to treat bleeding from the mouth or nose or mild intestinal bleeding.
Researchers are trying to find ways to correct the faulty genes that cause hemophilia. Such gene therapy hasn’t yet developed to the point that it’s an accepted treatment. But researchers continue to test gene therapies for hemophilia in clinical trials.