PB0286 - Specificity of the bleeding phenotype in children with von Willebrand disease

Sunday, June 23, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Alexander Poletaev

Head of the Laboratory of Clinical Hemostasis
Dmitry Rogachev National Medical Research Centеr of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia

Co-Author(s)

Elena A. Seregina, PhD

Leading Researcher
Dmitry Rogachev National Medical Research Centеr of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia
DF

Darya Fedorova

Hematologist
Dmitry Rogachev National Medical Research Centеr of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia
DF

Dmitry Florinskiy

Hematologist of Outpatient Consultative Unit, P.h.D.
Dmitry Rogachev National Medical Research Center Of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia
AP

Alexey Pshonkin

Hematologist, Head of day hospital department, P.h.D.
Dmitry Rogachev National Medical Research Center Of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia
PZ

Pavel Zharkov

Doctor of Science, Head of Hemostasis Pathology Unit
Dmitry Rogachev National Medical Research Center Of Pediatric Hematology, Oncology and Immunology
Moscow, Moskva, Russia

Background: Von Willebrand disease - the most common hereditary bleeding disorder. The difficult of diagnosis consist in the wide variability of clinical manifestations and laboratory results, especially in children

Aims: To evaluate the specific clinical manifestation and specific laboratory results in children with vWD

Methods: There were 70 children under the age of 18 year enrolled of this study. The severity of bleeding was assessed on the PBQ scale, with the calculation of the final bleeding score. The concentration of antigen, ristocetin-cofactor activity of von Willebrand factor(vWf) and activity of blood coagulation factor VIII were evaluated in all patients.

Results: The mean score PBQ was 4.03 points, median 3 points. The minimum PBQ was 0 point, the maximum was 15 points. The average age of the debut vWD was 3.3 years (median is 2 years, 0-16 years). Out of 70 patients, 41 (58.6%) patients corresponded to type 1, 7 (10%) patients corresponded to type 3, and 22 (31.4%) patients corresponded to type 2 vWD. Most frequently occurring bleeding symptoms were epistaxis(70%) and cutaneous bleeding(60%). 30% of patients was need of treatment, including blood transfusion, desmopressin or coagulation-factor concentrate. Higher age was not associated with a higher PBQ score in children(p=0.3). There is no difference between boys and girls PBQ score (median 2 vs. 3, p=0.67). PBQ score differed significantly between VWD type 1 and 3, 2 and 3: median 3(0–9) and 7(6–15), 4(1–12) and 7(6–15), respectively(p < 0.001). More than a quarter of the patients had a normal level of vWF, of which 52% were patients with type 1 vWD and 48% were patients with subtypes of type 2 (2A, 2B, 2M). PBQ score was not associated with VWF(p=0.7) and FVIII levels(p=0.6)

Conclusion(s): In children with VWD the bleeding phenotype is not associated with type of VWF and VWF activity and FVIII levels