Hemophilia A

• Quantitative or functional deficiency of factor VIII

• X-linked recessive; bleeding has been seen in heterozygous women, most likely it’s due to unfavorable mosaicism

• About 30% of patients have no family history and get the d/o through a new mutation

• Bleeding characteristics

  • May have life-threatening spontaneous, post-traumatic, or post-surgical bleeding

  • Often see hemarthroses and joints may be crippled if recurrent

  • Minor cuts don’t bleed too much because platelets are normal; petechiae are usually absent

  • The aPTT is prolonged, and bleeding time, PT time, and platelet counts are normal

• Factor VIII transfusions carried HIV risk until recently

• Severity relates to amount of functional factor VIII

  • Severe = < 1% of normal factor VIII levels

  • Moderate = 1% to 5% of normal

  • Mild = 6% to 50% of normal

• About 15% of patients develop Abs to factor VIII

Category: Medical Subject Notes , Pathology Notes