A prospective evaluation of the prevalence of symptomatic von Willebrand disease (VWD) in a pediatric primary care population.

The prevalence of von Willebrand disease (VWD) is reported as approximately 1%; however, these estimates were not based on individuals with significant symptoms. Four thousand five hundred ninety-two unselected parents/children were asked: "Does your child have a problem with bleeding/bruising?"; 223 (5%) answered yes, 41 of whom were administered the validated Pediatric Bleeding Questionnaire and had VWF testing. Five were diagnosed with VWD (three type 1, one type 2A, one type 2B). The prevalence of bleeding/bruising in a general pediatric population is 5%; the prevalence of symptomatic VWD at the level of pediatric primary care is at least 1 in 1,000.