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Published on: September 9, 2012
Why factor XI deficiency is a clinical concern
Allison P Wheeler1,2, David Gailani1,3
1a Department of Pathology, Microbiology and Immunology , Vanderbilt University , Nashville , TN , USA.
Introduction:
Inherited fXI deficiency has been an enigma since its discovery in 1953. The variable and relatively mild symptoms in patients with even the most severe form of the disorder seem out of step with the marked abnormalities in standard clotting assays. Indeed, the contribution of factor XI to hemostasis in an individual is not adequately assessed by techniques available in modern clinical laboratories.
Areas Covered:
We discuss clinical studies, genetic/genomic analyses, and advances in laboratory medicine that are reshaping our views on the role of factor XI in pathologic coagulation. We review how the disorder associated with factor XI deficiency has contributed to changes in blood coagulation models, and discuss the complex genetics of the deficiency state and its relationship to bleeding. Finally, we cover new laboratory approaches that may distinguish deficient patients who are prone to bleeding from those without such predisposition. Expert commentary: Advances in understanding the biology of factor XI have led to modifications in treatment of factor XI-deficient patients. Factor replacement is used more judiciously, and alternative approaches are gaining favor. In the future, better laboratory tests may allow us to target therapy to those patients who would benefit most.
Insights
Inherited factor XI (fXI) deficiency presents mild symptoms despite severe clotting assay abnormalities. New research clarifies fXI
Area of Science:
- Hemostasis and Thrombosis
- Genetic Blood Disorders
Background:
- Inherited factor XI (fXI) deficiency, known since 1953, exhibits a puzzling discrepancy between mild clinical symptoms and severe clotting assay results.
- The precise role of fXI in hemostasis remains unclear, as current laboratory tests inadequately assess its contribution in individuals.
Purpose of the Study:
- To review current clinical, genetic, and laboratory advancements that are redefining the understanding of factor XI's role in coagulation.
- To explore the complex genetics of fXI deficiency and its correlation with bleeding tendencies.
- To discuss novel laboratory methods for identifying fXI-deficient individuals at risk of bleeding.
Main Methods:
- Discussion of clinical studies and genetic/genomic analyses.
- Review of advances in laboratory medicine and coagulation models.
- Examination of new diagnostic approaches for bleeding risk assessment in fXI deficiency.
Main Results:
- Understanding fXI biology has led to revised treatment strategies for fXI deficiency.
- Factor replacement therapy is now used more cautiously, with alternative treatments gaining prominence.
- Emerging laboratory tests show promise in differentiating bleeding-prone patients from those without bleeding risk.
Conclusions:
- Factor XI's role in hemostasis is complex and not fully captured by standard assays.
- Advances in research are improving the diagnosis and management of factor XI deficiency.
- Future laboratory diagnostics will enable more targeted and effective patient therapies.
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