title: Factor V Leiden mutation in cerebral venous thrombosis.
abstract: OBJECTIVE
  Resistance to activated protein C is a common inherited risk factor for venous thrombosis, which is due to a mutation in coagulation factor V (factor V Leiden mutation). It is present in approximately 20% of unselected consecutive patients with deep vein thrombosis. The rate of resistance to activated protein C in patients with cerebral venous thrombosis (CVT) is unknown.
  
  
  METHODS
  We investigated the association of factor V mutation with CVT using a case-control study. Nineteen unselected patients with CVT and 57 healthy control subjects were tested for the point mutation.
  
  
  RESULTS
  The mutation was found in a heterozygous form in 4 of the 19 patients with CVT (21%) and in only 1 of the 57 control subjects (2%) (P = .02, Fisher's exact test). The prevalence of the coagulation defect found in our patients with CVT was consistent with that observed in previous studies in patients with deep vein thrombosis. In 3 of the 4 patients positive for the mutation, CVT developed in the presence of an acquired prothrombotic state, including oral contraceptive use in 2 patients and puerperium in the third.
  
  
  CONCLUSIONS
  Factor V Leiden mutation is a risk factor for CVT and may be the most common inherited coagulation defect associated with this condition.
authors.affiliation: Service de Neurologie, Centre R. Garcin, Hôpital Sainte-Anne, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Zuber
authors.forename: P
authors.initials: P
authors.lastname: Toulon
authors.forename: L
authors.initials: L
authors.lastname: Marnet
authors.forename: J L
authors.initials: JL
authors.lastname: Mas
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002550:Cerebral Veins; D003276:Contraceptives, Oral / Q000009:adverse effects; D005165:Factor V / Q000235:genetics*; D005260:Female; D006579:Heterozygote; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011644:Puerperal Disorders / Q000235:genetics; D012307:Risk Factors
chemical_list: D003276:Contraceptives, Oral; C095381:factor V Leiden; D005165:Factor V