title: Association of severe haemophilia A and factor V Leiden: report of three cases.
abstract: The clinical severity of haemophilia is usually related to residual clotting factor activity. Reports of factor V deficiency or protein C have been described in haemophilic patients and both are involved in the activated protein C pathway. Recently, the poor response to activated protein C due to factor V Leiden (FQ506) has been associated with an increased risk of thrombosis and its incidence in the normal population is given as 2-7%. We describe three cases of severe haemophilia A heterozygous for factor V Leiden and its influence on phenotype.
authors.affiliation: Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, and Department of Internal Medicine, School of Medicine, Escola Paulista de Medicina, Säo Paulo, Brazil Valder R. Arruda, M.D., Ph.D., Haematology-Haemotherapy Centre, UNICAMP, CP 6198, CEP 13.081-970, Campinas, SP, Brazil.*Joyce M. Annichino-Bizzacchi, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.Sandra V. Antunes, M.D., Haematologist, Department of Internal Medicine, Escola Paulista de Medicina, Säo Paulo, SP, Brazil.Fernando F. Costa, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.
authors.forename: V R
authors.initials: VR
authors.lastname: Arruda
authors.affiliation: Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, and Department of Internal Medicine, School of Medicine, Escola Paulista de Medicina, Säo Paulo, Brazil Valder R. Arruda, M.D., Ph.D., Haematology-Haemotherapy Centre, UNICAMP, CP 6198, CEP 13.081-970, Campinas, SP, Brazil.*Joyce M. Annichino-Bizzacchi, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.Sandra V. Antunes, M.D., Haematologist, Department of Internal Medicine, Escola Paulista de Medicina, Säo Paulo, SP, Brazil.Fernando F. Costa, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.
authors.forename: J M
authors.initials: JM
authors.lastname: Annichino-Bizzacchi
authors.affiliation: Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, and Department of Internal Medicine, School of Medicine, Escola Paulista de Medicina, Säo Paulo, Brazil Valder R. Arruda, M.D., Ph.D., Haematology-Haemotherapy Centre, UNICAMP, CP 6198, CEP 13.081-970, Campinas, SP, Brazil.*Joyce M. Annichino-Bizzacchi, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.Sandra V. Antunes, M.D., Haematologist, Department of Internal Medicine, Escola Paulista de Medicina, Säo Paulo, SP, Brazil.Fernando F. Costa, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.
authors.forename: S V
authors.initials: SV
authors.lastname: Antunes
authors.affiliation: Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, and Department of Internal Medicine, School of Medicine, Escola Paulista de Medicina, Säo Paulo, Brazil Valder R. Arruda, M.D., Ph.D., Haematology-Haemotherapy Centre, UNICAMP, CP 6198, CEP 13.081-970, Campinas, SP, Brazil.*Joyce M. Annichino-Bizzacchi, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.Sandra V. Antunes, M.D., Haematologist, Department of Internal Medicine, Escola Paulista de Medicina, Säo Paulo, SP, Brazil.Fernando F. Costa, M.D., Assistant Professor, Haematology-Haemotherapy Centre, State University of Campinas, UNICAMP, Campinas, SP, Brazil.
authors.forename: F F
authors.initials: FF
authors.lastname: Costa
keywords: factor V gene; haemophilia; hypercoagulability; thrombosis