Abstract Number: PB0822
Meeting: ISTH 2022 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: High-molecular forms of von Willebrand factor (vWF) multimers(HMWM) play a major role in primary hemostasis, however, the contribution of the amount of HMWM to the severity of bleeding in children is not fully understood.
Aims: To evaluate the relationship between the HMWM vWF count and the severity of clinical manifestations in children with different types of vWD.
Methods: There were 35 children under the age of 18 year with different types of vWD enrolled of this study. Out of 35 patients, 16 (45.7%) patients corresponded to type 1, 2 (5.7%) patients corresponded to type 3, and 12 (40%) patients corresponded to type 2 vWD. The severity of bleeding was assessed on the PBQ scale, with the calculation of the final bleeding score. The vWF:Ag, vWF:RCo, activity of blood coagulation factor VIII, vWF collagen binding and vWF multimers were evaluated in all samples. For a quantitative assessment of the photograph of the gel, the Imagej program was used, where the HMWM amount was estimated of brightness of the bands.
Results: The mean score PBQ was 4.05 points, median 4 points. The minimum PBQ was 1 point, the maximum was 12 points. There were no correlations between the amount of HMWM vWF and the degree of bleeding for all types of vWD (rs=0,1, p=0,7), for 1 type(rs=0,02, p=0,9) and for 2A, 2B types (rs=0,13, p =0,8). It is noteworthy that of the two functional tests evaluating the work of the HMWM vWF, a strong inverse relationship was found between the number of HIMF and vWF:CB (rs=-0,81, p=0,015), while the dependence between the HMWM and vWF:RCo moderate and not significant (rs=-0,5, p=0,21).
Conclusion(s): The evaluation of the amount of vWF IMMF does not provide additional information in terms of assessing the severity of clinical manifestations and predicting the severity of hemorrhagic syndrome in children’s.
table
Correlations of laboratory parameters and the PBQ bleeding scale in patients with all types vWD
table
Correlations of laboratory parameters and the PBQ bleeding scale in patients with 2A,B types vWD
To cite this abstract in AMA style:
Poletaev A, Seregina E, Karamian N, Fedorova D, Pshonkin A, Plyasunova S, Zharkov P. A quantitative evaluation of high-molecular forms of von Willebrand factor multimers in children’s with different types of vWD. [abstract]. https://abstracts.isth.org/abstract/a-quantitative-evaluation-of-high-molecular-forms-of-von-willebrand-factor-multimers-in-childrens-with-different-types-of-vwd/. Accessed September 21, 2023.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-quantitative-evaluation-of-high-molecular-forms-of-von-willebrand-factor-multimers-in-childrens-with-different-types-of-vwd/