Clinical features and laboratory patterns in a cohort of consecutive Argentinian patients with von Willebrand's disease

Background and Objectives, von Willebrand's disease (VWD) is a bleeding dis order with variable clinical expression. Our aim was to classify patients w ith VWD and to determine the phenotype in their relatives. Design and Methods. The types and subtypes, blood group frequency and its r elevance, bleeding sites, response to the desmopressin (DDAVP) test, transf usion requirements and clinical features in type 1 and 2A families were det ermined in 1,885 patients. Results. Our findings were: type 1: 91%, type 2A: 3.1%, severe vWD: 1.3%; t ype 2N: 1.6%; type low intraplatelet: 2.7%; combined 1+2N: 0.3%. Blood grou p O prevalence was 70.5%. Bleeding and transfusion requirements were not co rrelated to blood groups. The most frequent symptoms were: ecchymoses-hemat omas 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 infu sed 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 m ore likely in subjects belonging to families with type 2A disease than in m embers of families with type 1 vWD in spite of these being symptomatic. Interpretation and Conclusions. These observations provide a good strategy to identify, classify and treat VWD patients without performing molecular a ssays. (C) 2001, Ferrata Storti Foundation.