Medicine & USMLE

Hemophilia C

  1. Common Pathway of Coagulation
  2. Extrinsic Pathway of Coagulation
  3. Intrinsic Pathway of Coagulation
  4. Hemophilia A
  5. Hemophilia B
  6. Hemophilia C
  7. Factor V Leiden
  8. Antithrombin-3 Deficiency


Hemophilia C is an autosomal recessive inherited bleeding disorder caused by a deficiency in clotting factor 11. Like most hemophilias, patients with hemophilia C present with symptoms of bleeding. This bleeding is usually milder than is seen in other hemophilias. The diagnosis of Hemophilia C can be supplemented by the lab finding of an elevated PTT.

Key Points

  • Hemophilia C
    • Pathogenesis
      • Deficiency of Factor XI
    • Genetics
      • Autosomal recessive inheritance
    • Presentation
      • Clinical symptoms are usually milder in this syndrome vs. Hemophilias A or B
      • Mild bleeding
        • Usually only detected with prolonged bleeding after trauma or surgery
    • Diagnosis
      • Definitive: Factor XI levels
      • Elevated PTT
        • Due to inhibited intrinsic coagulation pathway
      • Normal PT
        • Extrinsic (tissue factor) pathway is unaffected
      • Normal Bleeding Time
        • Platelet plug formation (primary hemostasis is unaffected)
    • Treatment
      • Recombinant Factor XI concentrate