Bleeding History in a Child Undergoing Surgery
Spero R. Cataland, MD, and Eric H. Kraut, MD
Ohio State University
Hemophilia A is an inherited bleeding disorder due to a deficiency of functional factor VIII. Factor VIII after proteolytic activation serves as a cofactor with factor IXa to activate factor X. Factor X then acts with factor V and a phospholipid surface to generate thrombin from prothrombin to form fibrin from fibrinogen to stabilize the developing clot. The gene for factor VIII is located on the long arm of the X chromosome, and thus almost all affected patients are male. Carrier females, however, may be found with factor VIII levels of less than 50%, and may have an increased bleeding risk with surgery or major trauma.
Hemophilia A typically develops secondary to a mutation in the gene, but in up to one third of patients the mutation may be spontaneous and not inherited. No single mutation accounts for all hemophilia A cases. Hundreds of deletions, inversions, and point mutations have been described.
The clinical severity of hemophilia correlates with the level of plasma factor VIII; the most severe patients have levels of less than 1%. These patients can bleed spontaneously into joints or muscles and may require frequent infusions of recombinant factor VIII or plasma-derived factor VIII to treat these bleeding episodes.
Table 1. Typical presentation abd symptoms in patients with hemophilia.
|Factor VIII and IX Activity||<1%||1-5%||>5%|
|Clinical Presentation||Early onset of symptoms (<2 years of age). Spontaneous bleeding into joints, muscles.||Later onset of symptoms. Bleeding after trauma, surgical procedures.||May go undetected until later in life. Very few or no bleeding episodes.|
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