Abstract Number: PB1104
Meeting: ISTH 2022 Congress
Background: Platelet microparticles are small membrane bound vesicles 0.1μm-1 μm in size that are shed from the platelet membrane during platelet activation, stress or apoptosis. They contribute phosphatidylserine externalisation to provide a procoagulant surface. Platelet microparticles also express functional platelet receptors (including CD41) and other bioactive effector molecules. Microparticles produced via transportation of samples as whole blood have been shown to produce reduced DRVVT screen ratio results (Cox-Morton, 2015).
We investigated whether platelet microparticles rich in procoagulant phospholipids are released during sample transport manifesting as a reduction in the clot time using the Stago PPL kit.
Aims: Does sample transportation impact the generation of microparticles that may contribute to previously identified false negative results for phospholipd assays such as Lupus Anticoagulant.
Methods: A reference range was established on samples collected from 20 normal donors. Residual patient samples were obtained following completion of routine testing. Classification of transported or non-transported was based upon available sample delivery information. PPL activity was measured using the Stago ProCoag-PPL (Stago, Asniers, France) kit on the ACLTOP 750 analyser (Werfen, Bedford, USA). Statistical analysis was performed using Microsoft Excel (Microsoft Corporation, USA). Differences in means were calculated with the Welch’s t-test for unequal variances. As multiple significance tests were applied the Bonferroni correction was applied to set a significance level of 0.025.
Results: A statistically significant increase in PPL activity (reduced clot time) was associated with transported samples (mean 30.0 +/- 11.8s) compared to patient samples taken in the adjacent clinical area (mean 50 +/- 5.88s).
Conclusion(s): With the introduction of Hub and Satellite laboratories transport of samples is a significant pre-analytical variable. Transportation of samples results in increased PPL activity from additional microparticle phospholipids being produced presumably due to platelet activation. This could be used in conjunction with dRVVT screen results to determine when transportation has affected lupus anticoagulant results.
To cite this abstract in AMA style:
Sharp M, Griffin J, MacDonald S. The effect of sample transportation on microparticle production measured in vitro using a procoagulant phospholipid activity assay. [abstract]. https://abstracts.isth.org/abstract/the-effect-of-sample-transportation-on-microparticle-production-measured-in-vitro-using-a-procoagulant-phospholipid-activity-assay/. Accessed March 21, 2024.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/the-effect-of-sample-transportation-on-microparticle-production-measured-in-vitro-using-a-procoagulant-phospholipid-activity-assay/