Hemophilia

Hemophilia means Hemo = blood; philein = to love

Hemophilia refers to several different hereditary deficiencies of coagulation in which bleeding may occur spontaneously or after only minor trauma. The effects of all forms of hemophilia are similar but each is a deficiency of a different blood clotting factor. The most common type (classic hemophilia) is hemophilia A. absence of factor VIII. People with hemophilia B lack factor IX.

Hemophilia A and B occur primarily among males, since these are sex-linked recessive disorders. A mider form is hemophilia C, a lack of factor XI which affects both males and females. Recall that factor XI activates factor IX. Hemophilia C is much less severe than hemophilia A and B because an alternate activator of factor IX is present, namely, factor VII. 

Hemophilia is characterized by spontaneous or traumatic subsutaneous and intramuscuar hemorrhaging, nosebleeds, blood in the urine, and hemorrhaging in joints that produce pain and damage. Treatment involves transfusions of fresh plasma or concentrates of the deficient clotting factor to relieve the bleeding tendency. 

Hemophilia C is much less severe than hemophilia A and B because an alternate activator of factor IX is present, namely, facttor VII.

Factor VIII concentrates are made by culling the factor from plasma of a very large number of donors. 

Sadly, between 1982 and 1985 most such factor VIII preparations were contaminated with HIV, the virus that causes AIDS and most hemophiliacs who used the products at that time became infected with HIV.