title: [Protein Z: a new factor of thrombophilia?].
abstract: BACKGROUND
  Sometimes, in front of a clinical setting of thrombophilia, the biological findings are helpless. Therefore we suggest to test a protein Z deficiency.
  
  
  METHODS
  Protein Z is a vitamin-K dependent protein forming a complex with the Z protein-dependent protease inhibitor for inhibiting the activated factor X; so protein Z acts as a "natural low molecular weight heparin". The prothrombotic phenotype associated with protein Z deficiency includes early fetal losses (before the 20th week of gestation), early and relapsing venous thrombosis in patients with factor V Leiden mutation and somehow ischaemic stroke in young people.
  
  
  CONCLUSIONS
  The protein Z deficiency seems to be associated with a particular prothrombotic phenotype including early fetal losses as well as early and relapsing venous thromboses in patients carrying the factor V Leiden mutation. It is unclear whether or not it plays a role as a thrombophilic factor especially in the arterial vascular field.
authors.affiliation: Service de médecine interne et immunologie clinique, CHU Jean-Minjoz, 2, boulevard Fleming, 25000 Besançon, France. nmagy@chu-besancon.fr
authors.forename: N
authors.initials: N
authors.lastname: Magy
mesh_terms: D000293:Adolescent; D000328:Adult; D001798:Blood Proteins / Q000235:genetics* / Q000502:physiology*; D004252:DNA Mutational Analysis; D006801:Humans; D010641:Phenotype; D020521:Stroke / Q000209:etiology; D019851:Thrombophilia / Q000235:genetics* / Q000503:physiopathology; D020246:Venous Thrombosis / Q000209:etiology
chemical_list: D001798:Blood Proteins; C026080:plasma protein Z