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How do hemophilia A and hemophilia B differ?
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bleeding and blood clotting
Red blood cells (erythrocytes) trapped in a mesh of fibrin threads. Fibrin, a tough, insoluble protein formed after injury to the blood vessels, is an essential component of blood clots.
Hemophilia A and hemophilia B are both hereditary bleeding disorders characterized by a deficiency in specific proteins required for blood coagulation. While they share similar clinical symptomsâsuch as an increased tendency for bruising, internal bleeding, and joint hemorrhagesâthey differ primarily in the specific clotting factor that is missing.1
- Hemophilia A: This is the most common form of the disease and is caused by a deficiency or inactivity of factor VIII. It is a sex-linked recessive disorder, meaning it is typically expressed in males and transmitted by female carriers.12
- Hemophilia B: Also known as Christmas disease, this form is caused by a deficiency of factor IX. Like hemophilia A, it is sex-linked and occurs almost exclusively in males.1
Management for both conditions involves avoiding injury and receiving infusions of the missing clotting factor, which can be produced via recombinant DNA technology. Additionally, gene therapy has shown effectiveness in treating the factor IX deficiency associated with hemophilia B.12