Clinical features of thrombophilia in families with gene defects in protein C or protein S combined with factor V Leiden

Blood Coagul Fibrinolysis. 1998 Jan;9(1):85-9. doi: 10.1097/00001721-199801000-00011.

Abstract

Twenty-nine clinically well-characterized, symptomatic index patients, 15 with protein C and 14 with protein S deficiency, in whom the genetic defect had been identified, were investigated for the presence of factor V Leiden. In six of 15 (40%) propositi with protein C and four of 14 (29%) with protein S deficiency, factor V Leiden was present. The age at first thrombosis was significantly lower (P < 0.001) in the ten propositi with a combined genetic defect (mean age 18.4 +/- 6.6 years) than in those with a single defect (mean age 32.6 +/- 10.4 years). Spontaneous occurrence, recurrence and site of thrombosis were similar in propositi with the single and the combined defect. Family studies led to the identification of a combined defect in 18 individuals from 11 families (11 propositi and 29 relatives), seven subjects had no abnormality, and in 15 a single defect was found. In individuals with a combined defect, thrombosis-free survival time was significantly shorter than in individuals with a single defect, even after exclusion of index patients. None of the seven individuals without genetic abnormality had experienced thrombosis. Our findings indicate a higher risk for development of thrombosis in individuals with a combined defect compared with those with a single defect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Blood Coagulation Disorders / blood
  • Blood Coagulation Disorders / epidemiology
  • Blood Coagulation Disorders / genetics*
  • Child
  • Child, Preschool
  • Factor V / genetics
  • Humans
  • Middle Aged
  • Mutation*
  • Prevalence
  • Protein C / genetics
  • Protein C Deficiency
  • Protein S / genetics
  • Protein S Deficiency / blood
  • Protein S Deficiency / epidemiology
  • Protein S Deficiency / genetics
  • Thrombophilia / blood
  • Thrombophilia / epidemiology
  • Thrombophilia / genetics*

Substances

  • Protein C
  • Protein S
  • factor V Leiden
  • Factor V