Inherited disorders are inborn and have some familial linkage. The hemophilias are inherited coagulation disorders.
Hemophilia A is a deficiency of coagulation factor VIII. It is the most commonly encountered hereditary based coagulation disorder. Hemophilia A is found almost exclusively in males, its pattern of inheritance is sex-linked recessive. This disorder presents clinically with hemorrhagic events ranging in severity from mild to severe. Patients often present with spontaneous bleeding into their joints, a classic symptom of this affliction. The treatment of hemophilia A often involves the administration of commercial factor VIII products.
Hemophilia B is a deficiency of coagulation factor IX. This disorder is also found almost exclusively in males, its pattern of inheritance is sex-linked recessive. Hemophilia B presents almost identically to hemophilia A in terms of symptoms, and has a very similar pattern of inheritance. Be sure to keep in mind that while similar, hemophilia A and B are caused by a deficiency in different coagulation factors. The treatment of hemophilia B involves therapeutic administration of Factor IX concentrates.