Hemophilia is a bleeding disorder caused by a lack of blood clotting factor. The disorder can be mild, moderate or severe, depending on the level of clotting factor. More than 15,000 people in the United States have hemophilia.

The condition is usually inherited from a parent with a genetic mutation. However, in about a third of patients, there is no family history of the disease and the disorder is caused by a new genetic mutation. Although most children with hemophilia have signs of bleeding during infancy or childhood, some people with mild hemophilia may not have symptoms until they're adults.

At UCSF, patients are treated at the Hemophilia Treatment Center, a federally designated Hemophilia Comprehensive Care Center. We provide a full range of services — including diagnosis, treatment, counseling and education — to both adults and children with hemophilia and other congenital bleeding disorders.

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Types of Hemophilia

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, also known as Christmas disease, named after Stephen Christmas, the first person diagnosed with the factor IX deficiency.

Hemophilia A and B occur almost always in males. A third, very rare type of hemophilia, sometimes called Hemophilia C, is caused by a lack of clotting factor XI, and occurs in both males and females.

Causes of Hemophilia

Hemophilia A and B are caused by genetic mutations in the gene for factor VIII or factor IX. Mutations are abnormal changes that occur in a gene. The gene for factor VIII and factor IX is located on the X chromosome, making Hemophila A and B X-linked disorders. As such, one copy of the abnormal factor VIII or factor IX gene results in hemophilia in males, and a carrier state in females.

When there is a family history of hemophilia, the mother usually is a carrier and half of her sons and some of her male relatives will have hemophilia. If there is no family history of hemophilia, the disorder is due to a new mutation that occurred either in the affected individual or in the individual's mother, whose carrier state may have gone unnoticed.

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The most common symptom of hemophilia is bleeding, particularly into the joints and muscles. When a person with hemophilia is injured, he does not bleed faster than a person without hemophilia, but it takes longer for bleeding to stop. Bleeding also may start 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 lead to permanent disability unless they are treated promptly.

Other symptoms of hemophilia include easy bruising, prolonged nosebleeds or vomiting of blood.

Symptoms and Severity of Hemophilia

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

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Accurate diagnosis is essential for the optimal management of hemophilia. Testing for hemophilia should be performed at a highly experienced specialized coagulation laboratory. Laboratories that do not frequently perform these specialized tests may not be able to accurately establish a diagnosis.

Most people with hemophilia are diagnosed at an early age. However, those with mild hemophilia may not be diagnosed until adulthood when they experience a bleeding episode due to trauma or surgery.

Hemophilia is diagnosed with 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 that your doctors know the clotting factor your relatives are missing. You will probably be missing the same one.

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Our health care team can help you decide which is the best treatment option for you. We rely on your input to help develop a plan of care that will keep you healthy, active and able to live successfully with the challenges of hemophilia.

The present goal of hemophilia therapy is to raise factor levels, decrease the frequency and severity of bleeding episodes and prevent complications of bleeding. Hemophilia treatment uses clotting factor concentrate, also called "factor," which 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 products, are made from donated human blood plasma. Others, called recombinant factor products, are made in a laboratory.

Clotting factor concentrate is injected into your vein soon after you have had an injury or show signs of bleeding. When clotting factor is given, 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 Medical Center.

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Hemophilia Treatment Center
400 Parnassus Ave., 4th Floor
San Francisco, CA 94143
Phone: (415) 353-2421
Fax: (415) 353-2467
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