title: Factor V Leiden is not common in children with portal vein thrombosis.
abstract: Portal vein thrombosis (PVT) is a rare condition affecting both children and adults, and occurs in association with a wide variety of clinical situations. On the other hand, the development of PVT in patients under these situations indicates that other contributing factors could be involved. Recently a missense mutation in the factor V gene (1691G-->A), known as factor V Leiden, has been identified and results in abnormal factor V product, resistant to proteolytic inactivation by activated protein C and thus predisposes to thrombosis. This study was carried out to verify if children with PVT have an increase in frequency of factor V Leiden. Allele-specific restriction analysis and single strand conformational polymorphism (SSCP) were used to test for factor V Leiden in 20 children with PVT and 64 normal children. None of the PVT children were heterozygous or homozygous for the factor V Leiden, and one control child was heterozygous. This study demonstrates that factor V Leiden is not common in children with PVT, and is not a prerequisite for this thrombotic event.
authors.affiliation: Department of Pediatrics, São Francisco University, Bragança Paulista, SP, Brazil.
authors.forename: C A
authors.initials: CA
authors.lastname: Seixas
authors.forename: G
authors.initials: G
authors.lastname: Hessel
authors.forename: C C
authors.initials: CC
authors.lastname: Ribeiro
authors.forename: V R
authors.initials: VR
authors.lastname: Arruda
authors.forename: J M
authors.initials: JM
authors.lastname: Annichino-Bizzacchi
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004198:Disease Susceptibility; D005165:Factor V / Q000032:analysis* / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D011169:Portal Vein; D013927:Thrombosis / Q000453:epidemiology / Q000235:genetics*
chemical_list: C095381:factor V Leiden; D005165:Factor V