Hemophilia is a disorder that prevents blood from clotting properly, resulting in bruising and bleeding. Caused by a defective gene, it affects about one in 5,000 boys born in the United States. Although hemophilia typically is inherited, a third of cases may result from a new genetic mutation. In children with hemophilia, one of the 11 blood clotting factors — proteins that help stop bleeding — is missing or reduced.

The most common type of hemophilia, caused by a lack of clotting factor VIII, is called Hemophilia A or classic hemophilia. The second most common type is caused by a lack of clotting factor IX and is called Hemophilia B or Christmas disease, named for Stephen Christmas, the first person diagnosed with the factor IX deficiency. Hemophilia A and B almost always occur in boys. A third, very rare type of hemophilia, called Hemophilia C, is caused by a lack of clotting factor XI and can occur in both girls and boys.

Hemophilia is caused by a mutation in the gene for factor VIII or factor IX. This occurs on the X chromosome, the chromosome inherited from the mother. If there is a family history of hemophilia, the mother is a carrier and her son will have the same type of hemophilia as her relatives. If there is no family history of hemophilia, the child's hemophilia is due to a new mutation and the mother may or may not be a carrier.

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At UCSF Benioff Children's Hospital, the pediatric Hemophilia Treatment Center offers the most comprehensive care for children with hemophilia throughout Northern California. Through our research, we also provide the latest advances in treating complications of the disease. UCSF is also a federally designated Hemophilia Comprehensive Care Center, designated by the Centers for Disease Control and Prevention, that cares for both adult and pediatric patients.

Children with hemophilia may qualify for coverage of medical expenses through California Children's Services and the Genetically Handicapped Persons' Program, and if severely disabled, for financial support from the Social Security Administration. A social worker at the Hemophilia Treatment Center can refer you to the appropriate resources.

Forms of Hemophilia

Hemophilia may occur in mild, moderate and severe forms, based on both the child's symptoms and the level or amount of clotting factor in the blood.

  • Mild Hemophilia — A child with mild hemophilia has 6 percent to 49 percent factor level and usually has problems with bleeding only after serious injury, trauma or surgery. In many cases, mild hemophilia is not discovered until a major injury, surgery or tooth extraction results in unusual bleeding. The first episode may not occur until adulthood.

  • Moderate Hemophilia — A child with moderate hemophilia has 1 percent to 5 percent factor level and has bleeding episodes after injuries, major trauma or surgery. He also may experience occasional bleeding without obvious cause. These are called spontaneous bleeding episodes.

  • Severe Hemophilia — A child with severe hemophilia has less than 1 percent factor level and has bleeding following an injury or surgery, and may have frequent spontaneous bleeding episodes into the joints and muscles.

A person's severity of hemophilia does not change over time. If a person's cells cannot make clotting factor during childhood, they will not have the ability to make clotting factor during adulthood.

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The most common symptom of hemophilia is bleeding, especially into the joints and muscles. When a child with hemophilia is injured, he does not bleed faster than a child without hemophilia. He bleeds longer. He may also start bleeding again several days after an injury or surgery. Small cuts or surface bruises usually are not a problem, but deeper injuries may result in bleeding episodes that can cause serious problems and lead to permanent disability unless treated promptly.

Symptoms of hemophilic bleeding depend on where the bleeding occurs. Infants may have bleeding from their mouth when they are cutting teeth, bite their tongue or tear tissue in their mouth. Toddlers and older children commonly have bleeding into muscles and joints. Symptoms of bleeding include pain, swelling, loss of range of motion and an inability to move or use the affected arm or leg. Usually there is no bruising or discoloration of the skin to indicate that the swelling and pain are due to blood.

Another symptom of hemophilia is easy bruising. Children with hemophilia may have many bruises of different sizes all over their bodies. Other symptoms of bleeding may be a prolonged nosebleed or vomiting of blood.

The diagnosis of hemophilia is made by blood tests to determine if clotting factors are missing or at low levels, and which ones are causing the problem. If you have a family history of hemophilia, it is important to tell your child's doctors which clotting factor your relatives are missing, since your child will be missing the same one.

If you know you are a carrier, the diagnosis of hemophilia can be made in your newborn soon after birth. Tests to determine if your baby has hemophilia can be run on blood obtained from the umbilical cord or drawn from the newborn's vein. You will be advised to delay some procedures, such as circumcision, until after you learn whether your child has hemophilia.

Some families with a history of hemophilia may want to request prenatal testing, or testing before birth. This testing can be done early in pregnancy, allowing your family to make informed decisions and preparations. UCSF Benioff Children's Hospital has genetic counselors who are available to help you make family planning decisions and arrange for prenatal testing, if desired.

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The present goal of therapy is to raise factor levels, decrease the frequency and severity of bleeding episodes and prevent the complications of bleeding. This is done by injecting the missing clotting factor into your child's vein soon after he has injury or shows signs of bleeding.

Clotting factor concentrate, also called "factor," is a dried powder form of the clotting factor. It is mixed with water to form a liquid before it is given. Some clotting factor products, called plasma-derived factor, are made from donated human blood plasma. Others, called recombinant factor, are made in a laboratory and do not use human blood proteins. Because recombinant products do not contain human blood, they are much safer since they avoid potential transmission of a virus from donated blood.

When clotting factor is administered, it immediately circulates in the blood so the body can use it to form a blood clot. Once the blood clot is established and the bleeding has stopped, the body begins to reabsorb the blood that has leaked into the tissues and joints.

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Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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UCSF Clinics & Centers

Cancer & Blood Disease

Hemophilia Treatment Center
1825 Fourth St., Sixth Floor
San Francisco, CA 94158
Phone: (415) 476-3831
Phone: (800) 476-0560
Fax: (415) 476-3301
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