Hemophilia A (factor VIII deficiency), hemophilia B (Christmas disease, factor IX deficiency). Both disorders will result in bleeding and hemorrhage.
- Hemophilia A is much more common than B.
Etiology
Both disorders are X-linked defects in genes coding for clotting factors, leading to their deficiencies.
- Factor VIII is a cofactor for factor IX of the intrinsic pathway produced by endothelial cells.
- Factor