Authors' objectives: The National Salaried Workers' Health Insurance Fund (CNAMTS) asked HAS to assess the value of the different laboratory tests for haemostasis abnormalities with a view to updating the section in the Nomenclature of Procedures in Laboratory Medicine (NABM) containing the procedures in laboratory medicine for measuring abnormalities of haemostasis (subsection 5-02). One of those procedures is testing for the G1691A mutation of the factor V gene (Leiden FV) and the G20210A mutation of the factor II gene. All methods of testing for point mutations can be used to test for the G1691A polymorphism of exon 10 of the FV gene and for G20210A of the untranslated region 3' of the FII gene. The reference technique is still bidirectional sequencing of a specific genetic region of the gene of interest. These methods can be used to identify mutations and to determine their type (homozygous or heterozygous). These examinations can be performed only by laboratories authorised to carry out genetic tests. The G1691A mutation of the factor V gene (FV) and the G20210A mutation of the prothrombin (or FII) gene are genetic variants, each due to a point mutation of the corresponding genes. These are biological risk factors for VTE. Their predictive value is however poorly defined, since there is no consensus among the various guidelines on this subject.

Authors' recommendations: According to the literature identified and analysed, tests for mutations of factors V and II are not indicated in unselected patients. Consensus indications are identified in all the guidelines analysed: - first episode of VTE: o unprovoked, and occurring before 50/60 years of age; o women of child-bearing age whether or not the episode is provoked; - recurrence of VTE: o any recurrence of proximal DVT and/or PE, the first episode of which occurred before 50/60 years of age; o any unprovoked recurrence of distal DVT; - personal history of VTE or pregnant women with a family history of VTE. Testing for mutations of FV and FII can also be suggested, after case-by-case discussion, in the following indications: - pregnant women with a family history of hereditary thrombophilia; - pregnant women with a history of multiple spontaneous abortions or unexplained intrauterine fetal death, preeclampsia, HELLP syndrome, premature detachment of the placenta or retarded fetal growth;

Project Status: Completed

URL for project: http://www.has-sante.fr/portail/jcms/c_1009982/en/biology-of-haemostasis-disorders?xtmc=&xtcr=42

Year Published: 2011

URL for published report: http://www.has-sante.fr/portail/upload/docs/application/pdf/2011-08/biologie_anomalie_hemostase_t7_mutations_fii_et_fv_-_rapport_devaluation_2011-08-10_14-55-5_348.pdf

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: France

Organisation Name: Haute Autorité de Santé

Contact Address: 2 avenue du Stade de France, 93218 Saint-Denis La Plaine Cedex, France. Tel: +33 01 55 93 71 88; Fax: +33 01 55 93 74 35;

Contact Name: has.seap.secretariat@has-sante.fr

Contact Email: has.seap.secretariat@has-sante.fr