Hemophilia

Hemophilia

Signs and Symptoms
Diagnosis
Treatment

Signs and Symptoms

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.

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.

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

• An individual with mild hemophilia has 6 percent to 49 percent of the normal factor level, and usually bleeds only after serious injury, trauma or surgery. The first episode of bleeding may not occur until adulthood.
• An individual with moderate hemophilia has 1 percent to 5 percent of the normal factor level and has bleeding episodes after injuries, major trauma or surgery. He also may experience occasional bleeding without obvious cause, called spontaneous bleeding episodes.
• An individual with severe hemophilia has less than 1 percent factor level and experiences 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 because factor level is determined by genetics. If a person cannot make clotting factor when he is young, he will never have the ability to make clotting factor.

Reviewed by health care specialists at UCSF Medical Center.
Last updated May 8, 2007