title: [Thrombophilia factors as inducers of retinal vascular occlusion].
abstract: OBJECTIVE
  Thrombophilic abnormalities and defects in the anticoagulant system, such as protein C or protein S deficiency, activated protein C resistance and factor V Leiden mutation, may produce retinal vascular occlusions.
  
  
  METHODS
  Blood samples from 66 consecutive retinal vascular occlusion patients were obtained and analysed for protein C resistance and fibrinolysis activity. Other thrombophilic and standard laboratory coagulant tests were also carried out.
  
  
  RESULTS
  An increased activity of factor VIII was found in 72% of the collective. Furthermore, 24% of all patients and 32% of patients younger than 45 years old were resistant to activated protein C. Nevertheless only one patient showed a homozygous factor V Leiden mutation.
  
  
  CONCLUSIONS
  Thrombophilic activity in cases of protein C resistance or factor V Leiden mutation may result in severe thrombotic manifestations in ocular vessels. Compared to the elderly, younger people showed a higher activated protein C resistance which seems be one of the most common causes for retinal vascular occlusion in this age group.
authors.affiliation: Universitäts-Augenklinik Magdeburg, Leipziger Strasse 44, 39120 Magdeburg. RCLerche@medizin.uni-magdeburg.de
authors.forename: R C
authors.initials: RC
authors.lastname: Lerche
authors.forename: C
authors.initials: C
authors.lastname: Wilhelm
authors.forename: B
authors.initials: B
authors.lastname: Eifrig
authors.forename: G
authors.initials: G
authors.lastname: Richard
mesh_terms: D020016:Activated Protein C Resistance / Q000097:blood*; D000328:Adult; D000368:Aged; D001780:Blood Coagulation Tests; D005165:Factor V / Q000235:genetics* / Q000378:metabolism; D005169:Factor VIII / Q000378:metabolism; D005260:Female; D005342:Fibrinolysis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015356:Retinal Artery Occlusion / Q000097:blood*; D012170:Retinal Vein Occlusion / Q000097:blood*; D012307:Risk Factors; D019851:Thrombophilia / Q000097:blood*
chemical_list: C095381:factor V Leiden; D005165:Factor V; D005169:Factor VIII