3.2 Hemophilia

• What is hemophilia?

  A bleeding disease occurring almost exclusively in males
• What percentage of hemophilia cases is caused by Factor VIII deficiency?

  85 percent
• What is hemophilia A also known as?

  Classic hemophilia
• How common is classic hemophilia in males in the United States?

  1 in every 10,000 males
• What causes the bleeding tendency in the remaining 15 percent of hemophilia cases?

  Deficiency of Factor IX
• How are Factor VIII and Factor IX transmitted?

  By way of the female chromosome
• Why is it rare for women to have hemophilia?

  They have two X chromosomes with appropriate genes
• What happens if a woman is a hemophilia carrier?

  She transmits the disease to half her male offspring
• What determines the severity of bleeding in hemophilia?

  The degree of genetic deficiency
• When does bleeding usually occur in hemophilia patients?

  After trauma
• How long can bleeding last after a tooth extraction in hemophilia patients?

  For days
• What are the two active components of Factor VIII?

  A large component and a smaller component
• What is the molecular weight of the smaller component of Factor VIII?

  About 230,000
• What is the role of the smaller component of Factor VIII?

  It is important in the intrinsic pathway for clotting
• What causes classic hemophilia?

  Deficiency of the smaller component of Factor VIII
• What is von Willebrand disease?

  A bleeding disease from loss of the large component
• What is the most effective therapy for severe prolonged bleeding in classic hemophilia?

  Injection of purified Factor VIII
• Why is the cost of Factor VIII high?

  It is gathered from human blood
• What is the benefit of recombinant Factor VIII?

  It makes treatment available to more patients
• What are the key characteristics of hemophilia?

  • Bleeding disease primarily in males
  • Caused by deficiencies of Factor VIII or IX
  • Severity varies based on genetic deficiency
  • Bleeding occurs mainly after trauma
  • Treatment involves Factor VIII injections
• What are the differences between hemophilia A and von Willebrand disease?

  • Hemophilia A: Deficiency of Factor VIII
  • Von Willebrand disease: Loss of large Factor VIII component
  • Hemophilia A primarily affects males
  • Von Willebrand disease can affect both genders