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Response to desmopressin in type IID von Willebrand's disease
N Thomas1, U O'Callaghan, G D Lowe
1Academic Department of Haematology, Royal Free Hospital, London, UK.
Abstract:
Dominant transmission of a variant of von Willebrand's disease (vWD) with aberrant polymerization of von Willebrand factor (vWF) has been identified in a Scottish family. Multimer analysis of plasma vWF from the propositus and her father revealed an identical pattern to that previously reported in families designated as type IID vWD. There is loss of the larger multimers and presence of an intermediate subsidiary band not seen in normal subjects or other vWD variants. Platelet/vWF interaction induced by ristocetin is not enhanced in these cases and the platelet vWF shows the same aberrant multimer pattern as plasma vWF. DDAVP infusion in two affected members of the Scottish family and in one of the index cases produced a rise in plasma vWF antigen and factor VIII. Higher molecular weight vWF multimers appeared transiently after infusion of desmopressin (1-deamino-8-D-arginine vasopressin, abbreviated DDAVP) coincident with shortening of the bleeding time. The platelet counts did not change after the DDAVP infusions. DDAVP should be considered for management of bleeding in this variant of von Willebrand's disease.
Insights
A rare von Willebrand
Area of Science:
- Hematology
- Genetics
- Molecular Biology
Background:
- Von Willebrand's disease (vWD) is a bleeding disorder.
- Aberrant polymerization of von Willebrand factor (vWF) causes a rare vWD variant.
Observation:
- A Scottish family presented with dominant transmission of vWD.
- Plasma vWF multimer analysis revealed loss of large multimers and a unique intermediate band.
- Platelet vWF showed the same aberrant multimer pattern.
Findings:
- Desmopressin (1-deamino-8-D-arginine vasopressin, DDAVP) infusion increased vWF antigen and Factor VIII.
- Higher molecular weight vWF multimers appeared transiently post-DDAVP.
- Bleeding time was shortened after DDAVP infusion without affecting platelet count.
Implications:
- DDAVP shows potential for managing bleeding in this vWD variant.
- Understanding vWF polymerization defects is crucial for diagnosis and treatment.
- This study contributes to the classification and therapeutic strategies for vWD subtypes.