Information ⬇
- Hemophilia A: incidence 1:5000; sex-linked recessive deficiency of factor VIII (low plasma factor VIII coagulant activity, but normal amount of factor VIII-related antigen—vWF). Laboratory features: elevated PTT, normal PT.
- Hemophilia B (Christmas disease): incidence 1:30,000, sex-linked recessive, due to factor IX deficiency. Clinical and laboratory features similar to hemophilia A.
- von Willebrand disease: most common inherited coagulation disorder (1:800-1000), usually autosomal dominant; primary defect is reduced synthesis or chemically abnormal factor VIII-related antigen produced by platelets and endothelium, resulting in abnormal platelet function.
Outline ⬆