title: An evaluation of the DDAVP infusion test with PFA-100 and vWF activity assays to distinguish vWD types in children.
abstract: von Willebrand disease (vWD) is classified into partial (type 1), qualitative (type 2), and total deficiency (type 3).The aims of the study were to evaluate prospectively the potency of the DDAVP infusion test together with von Willebrand factor (vWF) ristocetin cofactor (vWF:RCo), vWF antigen (vWF:Ag), factor VIII coagulant activity (FVIII:C), and platelet function analyzer (PFA)-100 to distinguish vWD types. Genetic analysis and multimeric analysis of vWF was not applied. We classified the 112 patients and 47 healthy children phenotypically according to the laboratory test results and bleeding severity score. PFA-100 closure times (CT), FVIII:C, vWF:RCo, vWF:Ag, ristocetin-induced platelet aggregation (RIPA), and the response of FVIII:C and vWF parameters to desmopressin (DDAVP) were used to define types 1, 2, and 3 vWD. Type 1 vWD is mild in 34 cases (vWF:RCo % 40-55), moderate in 29 (vWF:RCo %27-40), severe type 1 vWD or nonclassical type 2 vWD in 12 cases (vWF:RCo % 4-16), and type 2 vWD in 23 cases (vWF:RCo %4-38).The response to DDAVP of vWF parameters is normal in all patients with mild/moderate type 1 vWD, 6 patients with severe type 1 vWD or nonclassical type 2 vWD and 11 patients with type 2 vWD. In conclusion, this study showed that measurement of vWF:RCo, vWF:Ag, FVIII:C, and PFA-100 parameters can differentiate vWD types but not severe type 1 vWD or nonclassical type 2 vWD. In the differentiation of severe type 1 vWD and nonclassical type 2 vWD, DDAVP response may be used.
authors.affiliation: Department of Pediatric Hematology, Ege University Faculty of Medicine, Izmir, Turkey. drmehmetakin@yahoo.com.tr
authors.forename: Mehmet
authors.initials: M
authors.lastname: Akin
authors.forename: Deniz Yilmaz
authors.initials: DY
authors.lastname: Karapinar
authors.forename: Can
authors.initials: C
authors.lastname: Balkan
authors.forename: Yilmaz
authors.initials: Y
authors.lastname: Ay
authors.forename: Kaan
authors.initials: K
authors.lastname: Kavakli
mesh_terms: D001780:Blood Coagulation Tests / Q000379:methods; D002648:Child; D002675:Child, Preschool; D003894:Deamino Arginine Vasopressin / Q000008:administration & dosage*; D005169:Factor VIII / Q000378:metabolism; D005260:Female; D006490:Hemostatics / Q000008:administration & dosage*; D006801:Humans; D007223:Infant; D008297:Male; D010979:Platelet Function Tests / Q000295:instrumentation / Q000379:methods; D056725:von Willebrand Disease, Type 1 / Q000097:blood / Q000145:classification / Q000188:drug therapy; D056728:von Willebrand Disease, Type 2 / Q000097:blood / Q000145:classification / Q000188:drug therapy; D056729:von Willebrand Disease, Type 3 / Q000097:blood / Q000145:classification / Q000188:drug therapy; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D006490:Hemostatics; D014841:von Willebrand Factor; D005169:Factor VIII; D003894:Deamino Arginine Vasopressin