Platelets play a crucial role in normal haemostasis, and their contributions
to thrombotic disorders are critical. Mean platelet volume (MPV) can be an
important biomarker in the detection of platelet activation. Activated
platelets are an indicator of increased thrombotic risk among patients (De
Luca et al., 2014). Therefore, this parameter could theoretically be used as
a standard introductory screening test for determining thrombotic risks.
Moreover, MPV is quick to test, easily interpreted, and a significant marker
for events of thrombosis. However, the time from phlebotomy to analysis and
the type of anticoagulant used may influence the results of this test (Machin
and Briggs, 2010).
Aim: The purpose of this study was to
determine the anticoagulant effects on platelets stability over time and the
effect of platelet activation on MPV and platelet count to determine whether
MPV can act as a marker for platelet activation.
Method: Venous blood samples were collected
from 17 healthy male volunteers into tubes containing citrate or
ethylenediaminetetraacetic acid (EDTA). MPV and platelet count changes were
analysed at specific intervals. Platelets were activated using adenosine
diphosphate (ADP) at the concentration of 10 µM, and then platelet parameters
were measured using a Sysmex XS-1000i haematology analyser.
MPV measurements from EDTA samples presented significant changes at the second
day measurement (p = 0.011). However, no significant difference for citrated
MPV was seen (p = 0.061). A significant difference in the platelet count was
observed in citrate after the second day (p = 0.006). Nevertheless, platelet
counts in EDTA were not significantly different over the study period (p =
0.107). MPV measurements were significantly higher in EDTA participants’
samples treated with ADP compared to resting EDTA samples (p ˂ 0.001).
However, this was not the case in citrate or platelet-rich plasma (PRP). In
terms of platelet counts, only a significant difference was observed in
citrated ADP-treated samples when compared to resting citrated samples (p ˂
The study has shown that MPV can be used as a simple marker for platelet
activation and thrombotic risks, but EDTA would be the anticoagulant of
choice due to its ability to differentiate activated from resting platelets.
The stability of EDTA decreased compared to citrate would need to be taken
into account when performing such analyses and should be performed within
24hrs of phlebotomy.