Factor XI deficiency

From Dog

Factor XI deficiency (Hemophilia C) is a rare autosomal-recessive genetic form of canine hemophilia.

Factor XI is a contact phase protein that is part of the intrinsic pathway of coagulation and normally drives thrombin generation and fibrin formation. Deficiencies in this protein results in interruptions of the coagulation cascade and lack of activation of thrombin, resulting in delayed hemorrhage sometimes up to days after a surgical procedure.

This disease has been reported in both male and female Springer Spaniels, Great Pyrenees[1], Weimaraners and Kerry Blue Terriers[2].

Clinical signs are usually absent but in severe deficiencies (Factor XI < 30 normal activity), mild prolonged bleeding may occur after trauma or surgery. Other symptoms may appear, including delayed healing and spontaneous hematoma formation up to 3 - 4 days later.

Diagnosis is based on coagulation screening tests and detection of delayed partial thromboplastin and activated clotting times[3][4].

Acute bleeding crises may require administration of whole blood or fresh frozen cryoprecipitate plasma[5].

Most affected dogs are clinically normal between hemorrhagic crises.


  1. LIDA
  2. Knowler C et al (1994) Factor XI deficiency in Kerry Blue Terriers. J Am Vet Med Assoc 205(11):1557-1561
  3. Mischke R & Nolte I (1997) Optimization of prothrombin time measurements in canine plasma. Am J Vet Res 58(3):236-241
  4. Parry BW (1989) Laboratory evaluation of hemorrhagic coagulopathies in small animal practice. Vet Clin North Am Small Anim Pract 19(4):729-742
  5. Dodds WJ & Kull JE (1971) Canine factor XI (plasma thromboplastin antecedent) deficiency. J Lab Clin Med 78(5):746-752