title: Applying diagnostic criteria for type 1 von Willebrand disease to a pediatric population.
abstract: BACKGROUND
  Definitive diagnosis of type 1 von Willebrand disease (VWD) remains elusive in clinical practice. Both the International Society on Thrombosis and Haemostasis (ISTH) and the Hospital for Sick Children (HSC) have proposed diagnostic criteria for type 1 VWD, which include abnormal laboratory values, significant mucocutaneous bleeding history, and/or positive family history. The objective of this study was to apply ISTH and HSC criteria to a large pediatric population previously diagnosed with type 1 VWD. We hypothesized that a substantial number of patients would not meet these diagnostic criteria.
  
  
  METHODS
  We performed a retrospective medical record review of all type 1 VWD patients at a single children's hospital. Frequencies of fit for ISTH and HSC diagnostic criteria were calculated.
  
  
  RESULTS
  Of 201 patients, 4.5% and 34% met the ISTH and HSC definitions, respectively. An additional 15% (ISTH) and 56% (HSC) met the definition of possible disease. For each definition, criteria for significant bleeding were most likely to be met, while criteria for abnormal laboratory values were least likely. When defined as simply VWF:Ag 5-20 IU/ml, as recently proposed by the ISTH, only 9% of patients met the definition of type 1 VWD.
  
  
  CONCLUSIONS
  ISTH criteria failed to identify the majority of children and adolescents who presented to medical attention with significant mucocutaneous bleeding. Further work is needed to develop diagnostic criteria with improved clinical validity in the pediatric setting.
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Hyatt
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Bryce A
authors.initials: BA
authors.lastname: Kerlin
authors.forename: Sarah H
authors.initials: SH
authors.lastname: O'Brien
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D019411:Clinical Laboratory Techniques; D005192:Family Health; D005260:Female; D006470:Hemorrhage; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D017410:Practice Guidelines as Topic / Q000592:standards*; D012189:Retrospective Studies; D014842:von Willebrand Diseases / Q000175:diagnosis*