Also called: Classic hemophilia, Factor VIII deficiency, Christmas disease, Factor IX deficiency
Hemophilia is a rare bleeding disorder in which the blood does not clot properly. It usually runs in families. But there are times a person may be the first one in their family to develop hemophilia.
Platelets are blood cells that help clot the blood. Certain proteins in the blood, called clotting factors, help platelets stick together to form clots and stop bleeding. Hemophilia is caused by having little or no clotting factor. This means the blood does not clot fast enough when tissue is injured.
There are 12 clotting factors in the blood. Lacking even one of these clotting factors causes prolonged bleeding. Hemophilia is caused by a change (called a mutation) in a gene that provides instructions to proteins to form clots in the blood.
Hemophilia results in soft, unstable clots or no clot forming at all. Hemophilia does not cause a person to bleed faster than someone without the disorder, just longer. A person with hemophilia may bleed longer after an injury or may bleed internally or may bleed spontaneously. This can damage tissues, organs, and joints.
Hemophilia can be mild, moderate, or severe based on how much clotting factor is in the blood. In some cases, hemophilia may be life-threatening.
Treatment for hemophilia includes factor replacement therapy, which replaces missing proteins from the blood.
Hemophilia symptoms usually depend on how low the factor levels are. Signs and symptoms may include:
There are 3 types of hemophilia. The type of hemophilia a person has depends on which clotting factor is low or missing:
Hemophilia A is the most common type of hemophilia. It accounts for about 80% of all hemophilia cases and is 4 times more common than hemophilia B. Hemophilia affects about 20,000 people in the United States and about 400,000 people worldwide.
Hemophilia A and B are usually inherited, which means passed on from parent to child through genes. Hemophilia can also happen by a new gene change (mutation) that occurs before birth. This occurs in about 1 in 3 people with hemophilia.
Chromosomes are the proteins that carry genetic information. Males have a X chromosome and a Y chromosome (XY). Females have two X chromosomes (XX). The gene that causes hemophilia A and B is located on the X chromosome, so the disorder is usually passed from a mother to a male child.
Some females who carry the gene can have symptoms of increased bleeding such as heavy nosebleeds or heavy menstrual bleeding.
Inheritance from mother to child: A female carrier of hemophilia has a 50% chance of passing the gene on with each birth, depending on which X chromosome the child gets.
If the gene mutation is passed on to a male child, he will have hemophilia.
If the gene mutation is passed on to a female child, she will be a carrier.
Inheritance from father to child: Because a male child inherits the Y chromosome from their father, a father cannot pass the gene on to a male child. However, because the father provides one of the X chromosomes, every girl born to a male with hemophilia will be a carrier.
Unlike hemophilia A or B, hemophilia C (factor XI deficiency) is passed on by either the mother or the father. Most people with factor XI (11) deficiency will have few bleeding symptoms or none at all.
It is not well known how the amount of factor XI (11) in a person's blood affects the severity of symptoms. Usually, factor XI (11) deficiency is a mild bleeding disorder, but this can vary widely, even among family members. This can make it hard to diagnose. Some people with only a mild deficiency in factor XI (11) can have serious bleeding episodes.
Hemophilia is diagnosed based on your child’s family and medical history, physical exam, and lab tests. If your child has symptoms or if your family has a history of bleeding disorders, your child’s care team will order blood tests. Your doctor may ask you about any changes in bleeding or bruising, recent illnesses, or medicines your child is taking.
Tests to diagnose hemophilia include:
Hemophilia A and B are classified based on the amount of factor VIII (8) or factor IX (9) a child has:
If your child is diagnosed with hemophilia, they will be treated by a hematologist, a doctor who specializes in treating blood disorders.
Treatment for hemophilia is based on disease severity, the child’s activity level, and medical or dental procedures needed. Current therapies include:
Replacement therapy is the main treatment for hemophilia. This treatment replaces the clotting factor that is low or missing in the blood.
Clotting factor medicines for replacement therapy can be made from the plasma of donated blood (plasma factor concentrate). Plasma is the part of the blood that has clotting proteins. Clotting factors for replacement therapy can also be man-made concentrates called recombinant clotting factors.
Replacement therapy for hemophilia is given in a vein by IV and can be given at a medical clinic or at home by a trained caregiver. After the clotting factor is given, it works quickly to increase the factor levels.
Treatment with factor products may be given either preventatively (called prophylaxis or prophy) or as needed for bleeding symptoms as they occur. The decision to start prophylaxis is made between the hematologist and the family. However, research has shown that children with hemophilia who were treated regularly to prevent bleeding had less joint damage by age 6 than did children who were only treated after a bleed started.
Emicizumab (HEMLIBRA®) is a medicine used to help prevent bleeding events in patients with hemophilia A, a factor VIII (8) hemophilia. Emicizumab mimics the role of factor VIII (8) and helps the blood to clot.
Since emicizumab is not actual factor VIII (8), it works even in patients with inhibitors. Emicizumab is given as an injection under the skin once a week, every other week, or every 4 weeks to prevent bleeding.
This medicine is used for prevention only. It should not be used to treat an active bleed. It will only work in factor VIII (8) hemophilia and not factor IX (9). If bleeding events occur, the patient needs to infuse factor VIII (8) concentrate (or Factor VIIa in the case of inhibitor) to treat the bleed.
DDVAP is a man-made hormone used to treat some people with mild hemophilia A. It is not used to treat hemophilia B or severe hemophilia.
DDAVP causes the release of von Willebrand factor from where it is stored in the lining of the blood vessels and in platelets. Von Willebrand factor is bound to factor VIII (8) in the blood. Without von Willebrand factor, factor VIII (8) is destroyed quickly. Because it is bound to factor VIII (8), von Willebrand factor increases the amount of the clotting factor VIII (8) in the blood.
Treatment with DDAVP is only given in certain situations, such as before a dental procedure to help reduce or prevent bleeding. If used often, this medicine will not work as well.
Some people do not have a good increase in their factor VIII (8) levels with DDAVP. To see if your child will have a good response, your care team may order a DDAVP challenge. This will measure the amount of factor VIII (8) in the blood before and after being given the medicine.
Antifibrinolytic medicines are used to help keep blood clots together once they are formed. These medicines include tranexamic acid (Lysteda®) and aminocaproic acid (Amicar®).
Antifibrinolytic medicines may sometimes be used along with clotting factor replacement therapy or DDAVP. These medicines are usually taken before and after a dental procedure. They are used to stop bleeding from the mouth or nose or to treat heavy menstrual cycles.
Scientists are studying new gene therapy treatments for hemophilia. Gene therapies work by changing or repairing genes to correct the genes that cause hemophilia. Researchers continue to test gene therapy in clinical trials to find ways to prevent or reduce bleeding in people with hemophilia.
A person with mild hemophilia may only have problems with bleeding after surgery or a traumatic injury. If the level of clotting factor is very low, a person may also have spontaneous bleeding episodes, often into the muscles and joints with little or no injury.
Hemophilia is a lifelong disorder with no cure. However, most people with hemophilia have a normal life expectancy. With the right treatment and proper self-care, your child can live a healthy, active life.
Tips for families include:
Always have factor medicine supplies on hand. This is important in both emergency and non-emergency situations. Always infuse first.
Emergency treatment: In an emergency, like a head injury, take your child and the factor medicine you have to the nearest emergency room. The emergency room care team will mix and infuse the factor treatment through an IV in your child’s arm. This gives your child the factor needed to stop bleeding. Even in the emergency room, the infusion should take priority over X-ray, labs, or other tests.
Non-emergency treatment: If your child has a minor injury, infuse the factor medicine yourself at home. You can help prevent pain, swelling, and potential joint damage if you infuse and then follow-up with RICE treatment (rest, ice, compression, and elevation).
Joint bleeds are the most common type of bleeds in people with hemophilia. These bleeds can happen in any joint, but they are most common in the knees, elbows, and ankles. Treating these bleeds is vital because they can damage the joint.
Early signs and symptoms of a joint bleed:
Late signs and symptoms of a joint bleed:
If you suspect a joint bleed, always follow the care instructions in your treatment plan for any joint bleed. Call your child’s care team if you are unsure about your next steps.
Treat your child with factor at home immediately. Then:
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Reviewed: December 2024
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