Changing insights in the diagnosis and classification of autosomal recessive and dominant von Willebrand diseases 1980-2015

Figure 12 Absence of large and intermediate von Willebrand factor multimers in severe dominant von Willebrand disease type 2 A, with absence of ristocetin-induced platelet aggregation and strongly prolonged Ivy bleeding times in a case with the S1506L mutation[44]. The responses of VWF parameters to DDAVP are very poor with no correction of Ivy bleeding times (BT) and no re-appearance of large VWF multimers in this case with dominant severe VWD 2A Group I indicating impaired assembling, transport and proteolysis of intracellar VWF multimers caused by the mutation S1506L near to the VWF cleavage site in the A2 domain of the VWF gene. VWD: Von Willebrand disease; VWF: Von Willebrand factor; DDAVP: Desmopressin; NP: Normal plasma; P: Patient.