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Understanding Hemophilia

Understanding Hemophilia -- the Basics

What Is Hemophilia?

Hemophilia refers to a group of inherited disorders that cause abnormal bleeding. The bleeding occurs because part of the blood -- called plasma -- has too little of a protein that helps blood clot.

Symptoms of hemophilia range from increased bleeding after trauma, injury, or surgery to sudden bleeding with no apparent cause. There are two types of hemophilia:

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  • Hemophilia A -- also called classic hemophilia -- is most common and occurs in about 80% of people with hemophilia.
  • Hemophilia B -- also called Christmas disease -- is less common and occurs in about 20% of people with hemophilia.

Hemophilia A

Hemophilia A results from too little of a plasma protein called factor VIII, which helps blood clot. The greater the deficiency, the more severe the symptoms.

  • Mild hemophilia: 5% to 40% of the normal factor VIII level
  • Moderate hemophilia: 1% to 5% of the normal factor VIII level
  • Severe hemophilia: Less than 1% of the normal factor VIII level

Most people who have hemophilia A have moderate or severe symptoms.

Hemophilia B

Hemophilia B results from too little of a plasma protein called factor IX, which helps blood clot. As in hemophilia A, hemophilia B can be mild, moderate, or severe. The greater the deficiency, the more severe the symptoms.

Recognizing Hemophilia

If there is no family history of hemophilia, an infant would not be tested for the condition. However, if there is a family history of hemophilia, specific tests can be done from an umbilical cord blood sample to see if a newborn infant has hemophilia. In fact, if the family desires, such testing can be done before a child is born.

For moderate or severe hemophilia, doctors and caregivers usually don't see any signs of the condition at birth or even for some time afterward. Symptoms in children may include:

  • Heavy bleeding in a male baby after circumcision
  • Excessive bruising or unusual bleeding during teething
  • Swollen, bruised joints or muscles when learning to walk
  • Frequent falls and bumps

For mild hemophilia, you may not have any noticeable symptoms until you undergo a dental procedure, which may cause you to bleed heavily, or you may not have any unusual bleeding unless you are injured in an accident or have surgery.

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