Abstract Number: PB1571
Meeting: ISTH 2020 Congress
Theme: Platelet Disorders and von Willebrand Disease » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: We hypothesized that the response to desmopressin acetate (DDAVP) in type 2 VWD might be related to genotype. If this is the case, it may be possible to individualize the treatment of these individuals.
Aims: To evaluate the response to DDAVP response and its relationship with genotype in type 2 VWD (except subtype 2B).
Methods: The study was cross-sectional. We collected data of type 2 VWD patients registered in two hemophilia treatment centers in Brazil after informed consent. The project was approved by the Ethics Committee of each institution. We used the Bleeding Assessment Tool (BAT) from International Society on Thrombosis and Haemostasis (ISTH). DDAVP challenge test was performed in all participants, except in individuals with subtype 2B. The identification of FVW gene variants was performed in all probands by Sanger sequencing of exons 17, 18, 20 and 28. We consulted the ISTH database to identify VWD gene variants associated with type 2 VWD.
Results: Twenty unrelated probands were evaluated, with a median age of 36 years (interquartile range [IQR], 16-49), 50% female. VWD was classified into subtypes 2A and 2M in 30% and 20% of participants, respectively. Among the probands, the median BAT was 7.5 (IQR, 4.5-11.0), 40% had a history of consanguinity and 40% responded to DDAVP test. Twelve variants were identified of which 9 (75%) were located in exon 28 and 8 (67%) were potentially pathogenic. Among the potentially pathogenic variants, individuals carrying Met740Ile and Arg1315Cys responded to DDAVP, while those carrying Val1360Ala, Arg1374Cys and Leu1580Val did not.
Conclusions: We showed that 40% of patients with VWD classified as subtypes 2A and 2M responded to DDAVP and that this response might be influenced by genotype. We are currently working on the collection of a larger sample of type 2 VWD patients to further study this association.
To cite this abstract in AMA style:
Maia GA, Freitas SDS, Cardoso PSR, Oliveira LC, Chaves DG, Rezende SM. Response to Desmopressin Acetate in Von Willebrand Disease Type 2 [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/response-to-desmopressin-acetate-in-von-willebrand-disease-type-2/. Accessed September 24, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/response-to-desmopressin-acetate-in-von-willebrand-disease-type-2/