Hemophilias

Hemophilias are rare, mainly X-linked diseases affecting males almost exclusively. Hemophilia A is due to an abnormality or deficiency of factor VIII, whereas hemophilia B (Christmas disease) is due to an abnormality or deficiency of factor IX. The incidences in the United States are 1:10,000 males for hemophilia A and 1:100,000 males for hemophilia B. An even rarer autosomal recessive variant, hemophilia C (Rosenthal syndrome), is caused by a deficiency or dysfunction of factor XI.

1. Clinical features. Patients usually present early in childhood with deep bleeding manifestations such as hemarthroses and soft tissue (eg, skeletal muscle) hematomas after minor trauma. Such events may be painful and recurrent, potentially resulting in significant complications such as hemophilic arthropathy. Laboratory tests demonstrate a markedly prolonged PTT with a normal PT and platelet count.
2. Treatment with the appropriate factor (in the form of a recombinant or lyophilized concentrate) should be coordinated perioperatively with the patient’s hematologist. Hemophilia A is treated with recombinant factor VIII to achieve preoperative activity levels of 25% to 100%, depending on the extent of the procedure. Some patients with mild hemophilia A may also respond to DDAVP therapy, which promotes release of factor VIII (with vWF) from the endothelium. If factor VIII is unavailable in an emergent situation, cryoprecipitate transfusion can provide the deficient factor, and antifibrinolytics such as TXA can reduce bleeding. Hemophilia B is treated with factor IX to achieve at least 30% to 50% activity before surgery.