title: Prothrombotic factors in children with stroke or porencephaly.
abstract: OBJECTIVE
  This study compared the frequencies of genetic and functional coagulation abnormalities in children with arterial ischemic stroke or porencephaly with frequencies in previously published studies.
  
  
  METHODS
  A series of 59 children (age 0-18 years) with arterial ischemic stroke or porencephaly were referred to the National Institutes of Health. A blood sample, buccal smear sample, questionnaire, and pedigree were requested for each child. Blood samples were analyzed for protein C (PC); protein S; antithrombin (AT); activated PC resistance (APCR); lipoprotein (a) [Lp(a)]; lupus anticoagulant; anticardiolipin antibodies; and the methylenetetrahydrofolate reductase C677T (MTHFR), factor V G1619A, factor II G20210A (PT), plasminogen activator inhibitor-1 4G6755G, and tissue factor pathway inhibitor C536T mutations. The frequency of each coagulation abnormality was compared with published international pediatric stroke case and control rates.
  
  
  RESULTS
  At least 1 prothrombotic abnormality was identified in 63% (36 of 57) of children studied, including plasminogen activator inhibitor-1 4G6755G (15 of 56), MTHFR (12 of 56), elevated Lp(a) (12 of 59), APCR (11 of 58), factor V G1619A (5 of 57), PT (3 of 57), PC deficiency (1 of 59), and AT deficiency (1 of 59). The MTHFR mutation, elevated Lp(a), the PT mutation, and AT deficiency rates were similar to rates in cases and more common than control subjects in previously published studies. The rate of children with APCR or multiple abnormalities was higher than in previous pediatric stroke studies. A family history of early thrombosis was identified in one third of the children with a prothrombotic abnormality.
  
  
  CONCLUSIONS
  Two thirds of children in this study had at least 1 of the prothrombotic risk factors tested, and several children had multiple risk factors. These results provide additional evidence that prothrombotic abnormalities are common among children with AIS or porencephaly.
authors.affiliation: National Institute of Neurological Disorders and Stroke, Building 10, Room 5S220, 10 Center Dr, MSC 1447, Bethesda, MD 20892-1447, USA. lynchj@ninds.nih.gov
authors.forename: John Kylan
authors.initials: JK
authors.lastname: Lynch
authors.forename: Christina J
authors.initials: CJ
authors.lastname: Han
authors.forename: Linda E
authors.initials: LE
authors.lastname: Nee
authors.forename: Karin B
authors.initials: KB
authors.lastname: Nelson
mesh_terms: D000293:Adolescent; D001777:Blood Coagulation; D019774:Blood Coagulation Factor Inhibitors / Q000032:analysis; D001779:Blood Coagulation Factors / Q000032:analysis; D001921:Brain / Q000002:abnormalities*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D020521:Stroke / Q000097:blood*; D013927:Thrombosis / Q000097:blood / Q000150:complications* / Q000235:genetics
chemical_list: D019774:Blood Coagulation Factor Inhibitors; D001779:Blood Coagulation Factors