Clinical profile of the association of P.R1205h and P.R924q in a patient with von Willebrand's disease

Abstract

von Willebrand's disease (VWD)-type Vicenza is characterized by a mild-moderate bleeding tendency, presence of ultralarge multimers (ULVWF), low von Willebrand's factor (VWF) and factor VIII (FVIII:C), attributed to reduced VWF survival, and the propeptide/ VWF ratio (VWFpp/VWF:Ag) is increased. Patients with p.R1205H had a 5-10-fold increase in FVIII and 5-fold increase in VWF:RCo after DDAVP, although their levels did not reach normal values. p.R924Q was previously reported as a polymorphism (SNP), in association with type 1 VWD, responsible of VWD2N phenotype by us, and the Brazilian group (Hemocentro UNICAMP, www.vwf.group.shef.ac.uk), as a marker of null allele, and as responsible for reductions in VWF and FVIII levels, particularly in combination with O blood group, and with a second mutation.