What is hemophilia?

• A. A hereditary bleeding disorder caused by deficiencies in clotting factors, primarily factor VIII or IX
• B. A deficiency of platelets
• C. A deficiency of von Willebrand factor
• D. An overproduction of clotting factors

Answer: (A)

Hemophilia is a hereditary bleeding disorder caused by deficiencies in specific clotting factors, most commonly factor VIII or factor IX. Without enough of these factors, the coagulation cascade cannot form a stable fibrin clot, leading to prolonged bleeding after injury and the tendency for spontaneous bleeding into joints and deep tissues. This condition is classically inherited in an X-linked recessive pattern, so it predominantly affects males, with female carriers sometimes showing milder symptoms. The other descriptions point to different problems: a platelet deficiency impairs the initial platelet plug formation; a deficiency of von Willebrand factor affects platelet adhesion and can cause mucous membrane bleeding; and an overproduction of clotting factors would promote clotting rather than bleeding.