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Factor XI deficiency

Niamh M O'connell1

  • 1The Katharine Dormandy Haemophilia Centre and Haemostasis Unit, The Royal Free and University College Medical School, London, UK.

Seminars in Hematology
|February 12, 2004
PubMed

Factor XI (FXI) deficiency leads to an injury-related bleeding diathesis, which is notable for the variability in the bleeding tendency and the lack of a clear relationship between bleeding and FXI coagulant activity. Bleeding in this disorder occurs especially in areas of high fibrinolytic activity. Although a rare disorder, the frequency of FXI deficiency is high in certain populations, notably persons of Ashkenazi descent and the Basque population of Southern France. In these populations, five mutations of the FXI gene have been identified and a founder effect has been confirmed for three of these. This paper reviews the role of FXI in coagulation and documents factors known to modify the bleeding tendency. Treatment of surgical bleeding in patients with FXI deficiency is reviewed with emphasis on the combined use of recombinant activated factor VII (rFVIIa; NovoSeven(R), Novo Nordisk, Bagsvaerd, Denmark) and the antifibrinolytic agent, tranexamic acid.

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