title: Clinical features and laboratory patterns in a cohort of consecutive Argentinian patients with von Willebrand's disease.
abstract: OBJECTIVE
  von Willebrand's disease (vWD) is a bleeding disorder with variable clinical expression. Our aim was to classify patients with vWD and to determine the phenotype in their relatives.
  
  
  METHODS
  The types and subtypes, blood group frequency and its relevance, bleeding sites, response to the desmopressin (DDAVP) test, transfusion requirements and clinical features in type 1 and 2A families were determined in 1,885 patients.
  
  
  RESULTS
  Our findings were: type 1: 91%, type 2A: 3.1%, severe vWD: 1.3%; type 2N: 1.6%; type low intraplatelet: 2.7%; combined 1+ 2N: 0.3%. Blood group O prevalence was 70.5%. Bleeding and transfusion requirements were not correlated to blood groups. The most frequent symptoms were: ecchymoses-hematomas and epistaxis and, in females over 13 years, also menorrhagia. Normal levels of factor VIII:C were found in 38.4% of the patients. DDAVP was infused in 567 patients with a good response in 80.6%. About 9% of our patients needed transfusion therapy. The diagnosis of von Willebrand's disease is more likely in subjects belonging to families with type 2A disease than in members of families with type 1 vWD in spite of these being symptomatic.
  
  
  CONCLUSIONS
  These observations provide a good strategy to identify, classify and treat vWD patients without performing molecular assays.
authors.affiliation: Department of Thrombosis and Hemostasis, Hematologic Research Institute of National Academy of Medicine of Buenos Aires, CONICET, Argentina.
authors.forename: A I
authors.initials: AI
authors.lastname: Woods
authors.forename: S S
authors.initials: SS
authors.lastname: Meschengieser
authors.forename: A N
authors.initials: AN
authors.lastname: Blanco
authors.forename: M J
authors.initials: MJ
authors.lastname: Salviú
authors.forename: C E
authors.initials: CE
authors.lastname: Farías
authors.forename: A C
authors.initials: AC
authors.lastname: Kempfer
authors.forename: M A
authors.initials: MA
authors.lastname: Lazzari
mesh_terms: D001118:Argentina / Q000453:epidemiology; D001789:Blood Group Antigens / Q000032:analysis; D015331:Cohort Studies; D005192:Family Health; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D008297:Male; D010641:Phenotype; D015995:Prevalence; D014842:von Willebrand Diseases / Q000097:blood / Q000453:epidemiology / Q000235:genetics*
chemical_list: D001789:Blood Group Antigens