Generalities:

Hemophilia is a rare disorder in which the blood does not clot normally. People with hemophilia lack a clotting factor or have a low amount of it, people can bleed a long time after an injury or accident. They may also bleed internally from the knees, ankles, and elbows. Bleeding into the joints causes pain and, when left untreated, can lead to arthritis. Brain hemorrhages are a very serious complication of hemophilia and require emergency treatment. The main signs and symptoms of hemophilia are excessive bleeding and easy bruising. Blood tests can detect it. The main treatment is injection of the missing clotting factor into the bloodstream. It can be done regularly or only when the person needs it.