Abstract Number: PB0482
Meeting: ISTH 2021 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Hemophilia - Basic
Background: Patients with haemophilia present individual differences in bleeding tendency despite similar levels of the clotting factors VIII (FVIII:C) and IX (FIX:C). In this context the additional presence of hereditary coagulopathies such as thrombophilia, deficiencies of other coagulation factors and impairment of primary haemostasis is discussed in the literature.
Aims: Analyzing primary haemostasis parameters mainly in pediatric patients with haemophilia A and B in comparison to a pediatric control group.
Methods: Specimens from 38 haemophilia patients (33 with haemophilia A: severe n=24, moderate n=1, mild n=8 and 5 with haemophilia B: severe n=3, moderate n=1, mild n =1) with a median age of 11 years (range: 1 to 32 years) and 30 healthy controls (median 5.5 years ranging from 1 to 19 years) were evaluated. Platelet function was investigated by impedance aggregometry and luminometry in whole blood, by light transmission aggregometry and flow cytometry in platelet rich plasma (PRP). Furthermore, the PFA 100® closure times, factor VIII- and IX-activities, von Willebrand factor parameters, hemogram, and blood group were determined. Informed consent was obtained.
Results: Patients showed a significant elevated maximal aggregation induced by arachidonic acid (final concentration: 0.5 mM) and collagen (1 µg/ml) in whole blood. In PRP a significantly reduced ADP-induced (5 µM) maximal aggregation was detected in the haemophilia group. A reduced CD63 expression induced by ADP was significantly more often seen in the patient’s group (50%) compared to controls (22%). CD63 expression by TRAP and mepacrine release showed no differences between the two groups. Patients had significantly lower platelet counts (median: 266.500/µl) compared to controls (312.000/µl.) No significant differences between the groups were detected for all other parameters.
Conclusions: Our data demonstrate only minor and most likely clinically non-relevant differences in primary haemostasis between patients with haemophilia and healthy controls.
The study was supported by an unrestricted grant from Intersero®.
To cite this abstract in AMA style:
Kürschner M, Lohse J, Boiti F, Tiebel O, Knöfler R. Evaluation of Primary Haemostasis in Children and Young Adults with Haemophilia [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/evaluation-of-primary-haemostasis-in-children-and-young-adults-with-haemophilia/. Accessed November 29, 2021.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/evaluation-of-primary-haemostasis-in-children-and-young-adults-with-haemophilia/