Hemophilia
Problems with bleeding too much
| Download this episode | There’s a good chance you’ve heard of hemophilia, a rare bleeding disorder in which the blood does not clot properly. This can lead to problems with bleeding too much after an injury or surgery. There are several different types of hemophilia. The most common are hemophilia A, which is caused by a lack or decrease of clotting factor 8, and hemophilia B, which is caused by a lack or decrease of clotting factor 9. Hemophilia B is also known as the Christmas disease but it has nothing to do with this time of year. In 1952 a five-year-old Canadian boy named Stephen Christmas was diagnosed with hemophilia but a pair of researchers found that the boy didn’t have a deficiency of clotting factor 8. Christmas had a different deficiency in blood clotting proteins and was lacking clotting factor 9. Until then, there was just one known type of hemophilia. The researchers named the condition Christmas disease after the young patient. | The gene for hemophilia is passed on from a parent to a child. When the father has hemophilia but the mother does not, none of the sons will have hemophilia. All of the daughters will carry the hemophilia gene without displaying any of the disease’s symptoms. Men have an X and a Y chromosome and women have two X chromosomes. The genes for hemophilia A and B are on the X chromosome. Since men have only one X chromosome, if they inherit the hemophilia gene, they will have the bleeding disorder. Because women have two X chromosomes, if one X chromosome has the hemophilia gene, the other X chromosome makes up for it. Women who have the hemophilia gene are called carriers, and they can pass it on to their children. When the mother is a carrier and the father is normal, for each child there is a 50 percent chance that a son will have hemophilia and a 50 percent chance that a daughter will carry the gene. | The symptoms of hemophilia are usually first noticed during infancy or childhood, such as when a male child is circumcised. Some people who have milder forms of the bleeding disorder, however, may not develop symptoms until later in life. Some of the common signs of hemophilia are unexplained bruises and bleeding into muscles and joints, especially the knees, elbow, and ankles. Spontaneous internal bleeding that occurs for no apparent reason or bleeding for a long time after getting a cut, removing a tooth, or having surgery are possible symptoms of the disease. For people with a family history of hemophilia, it’s possible to test the fetus during pregnancy to determine if the child is affected by the disease. Analysis of a blood sample from either a child or an adult can show a deficiency of a clotting factor. Sometimes, mild hemophilia isn’t diagnosed until after a person has undergone surgery and excessive bleeding results. | About 400 babies are born with hemophilia A each year. Based on a recent study that used data collected on patients receiving care in federally funded hemophilia treatment centers during the period between 2012 and 2018, as many as 33,000 males in the United States are living with the disorder. Many people who have or have had family members with hemophilia will ask that their babies get tested soon after birth. About one-third of babies who are diagnosed with hemophilia have a new mutation not present in other family members. In these cases, a doctor might check for hemophilia if a newborn is showing certain signs of hemophilia. To make a diagnosis, doctors would perform certain blood tests to show if the blood is clotting properly. If it does not, then they would do clotting factor tests, also called factor assays, to diagnose the cause of the bleeding disorder. These blood tests would show the type of hemophilia and the severity. | How a patient with hemophilia is treated depends on the type and severity of the disorder. The treatment usually involves replacement therapy, in which concentrates of clotting factors are given as needed to replace the blood clotting factors that are missing or deficient. These concentrates can be made from donated blood that has been treated and screened to reduce the risk of transmitting diseases such as hepatitis and HIV. Recombinant clotting factors, which are not made from human blood, are also available to further reduce the risk of infectious disease. Usually, people with mild hemophilia don’t require replacement therapy unless they are going to have surgery. In cases of severe hemophilia, treatment may be given as needed to stop bleeding when it occurs. Patients who have frequent bleeding episodes may be candidates for prophylactic factor infusions, which are given two or three times per week to prevent bleeding from occurring.
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Passed from a parent to a child
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Symptoms develop during childhood
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Tested soon after birth
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Replacement therapy
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