title: Prothrombotic abnormalities in children with venous thromboembolism.
abstract: OBJECTIVE
  The aim of this study was to determine the frequency of acquired or inherited prothrombotic disorders in a pediatric population with venous thromboembolism (VTE).
  
  
  METHODS
  From May 1992 to April 1998, 56 consecutive children with VTE were prospectively studied at a single center.
  
  
  RESULTS
  The median age was 8.4 years (range, 0.1-18 years). There was a male predominance. Fifty (89%) children had thrombosis in the lower venous system. Risk factors were detected in 54 (96%) children. Twenty-one (38%) thrombotic episodes were related to central venous lines. Family history of thrombosis was positive in 13 (23%) patients. In 26 (46%) patients, a prothrombotic disorder was detected. Nine of them had inherited disorders (protein C deficiency, 5 patients; protein S deficiency, 3 patients; Factor V Leiden mutation, 1 patient), and 13 children had acquired disorders (antiphospholipid antibodies, 5 patients; antithrombin deficiency, 8 patients). The remaining four showed combined abnormalities (Factor V Leiden mutation associated with inherited protein S deficiency, 1 patient; acquired antithrombin deficiency, 2 patients and inherited antithrombin deficiency, 1 patient).
  
  
  CONCLUSIONS
  In the series, a high percentage of prothrombotic disorders was detected; thus, a complete hemostatic evaluation should be performed in all of the children with VTE whether the patients have one or more risk factors.
authors.affiliation: Hematology-Oncology Department, Hospital de Pediatría, Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Bonduel
authors.forename: M
authors.initials: M
authors.lastname: Hepner
authors.forename: G
authors.initials: G
authors.lastname: Sciuccati
authors.forename: A F
authors.initials: AF
authors.lastname: Torres
authors.forename: G
authors.initials: G
authors.lastname: Pieroni
authors.forename: J P
authors.initials: JP
authors.lastname: Frontroth
mesh_terms: D000293:Adolescent; D001778:Blood Coagulation Disorders / Q000453:epidemiology* / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D020151:Protein C Deficiency / Q000453:epidemiology / Q000235:genetics; D018455:Protein S Deficiency / Q000453:epidemiology / Q000235:genetics; D011655:Pulmonary Embolism / Q000097:blood / Q000453:epidemiology / Q000235:genetics; D012307:Risk Factors; D013923:Thromboembolism / Q000097:blood / Q000453:epidemiology* / Q000235:genetics; D020246:Venous Thrombosis / Q000097:blood / Q000453:epidemiology* / Q000235:genetics