Von Willebrand's disease

Von Willebrand's disease, hereditary disease in which there is prolonged bleeding when the skin is injured. Unlike hemophilia, Von Willebrand's disease causes external bleeding; internal bleeding is rare. It affects both males and females and occurs most commonly in Scandinavian countries. The disease is caused by the absence of one of the clotting factors in the blood. Erik von Willebrand, a German professor of medicine, first identified the disease in 1926.