Sex-divided reference intervals for mean platelet volume, platelet large cell ratio and plateletcrit using the Sysmex XN-10 automated haematology analyzer in a UK population

Abstract

Background This study aimed to define the sex-divided reference intervals for platelet indices (mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR) and plateletcrit (PCT)) on the Sysmex XN-10. Methods A total of 2376 samples were assayed for full blood count on the Sysmex XN-10 haematology analyzer. After removing the outliers, reference intervals were calculated using the mean ± 2SD. The P value 0.05 was adopted to denote statistical significance. Results There was a statistical significance ( α = 0.05) between sex-divided reference intervals for MPV ( p = 0.007), P-LCR ( p = 0.015) and PCT ( p < 0.001), thus separate reference intervals were calculated for these indices, with orientation to the sex-divisions as follows: MPV, 9.1–13.0 fL [males] and 9.2–12.8 fL [females]; P-LCR, 17.6–47.0% [males] and 17.8–47.8% [females]; and PCT, 0.16–0.35% [males] and 0.18–0.37% [females]. No significance was found between sex-divided reference intervals for the PDW ( p = 0.838), therefore a reference interval for total individuals was calculated for this platelet measurement as 9.3–17.3 fL. Conclusion This study showed comparable reference intervals, using the Sysmex XN-10, with the previous literature. It determined the need to define sex-specific reference intervals for the MPV, P-LCR and PCT, but not for the PDW. These reference intervals will allow for low and high values to be facilitated in order to do further research and guide platelet disorder management.

Does gender influence reference values of platelet indices?

“…An important aspect was the sample size analyzed in the mentioned study and, as highlighted by Ali et al, the results obtained confirmed reports in the literature 14 . However, when compared to other studies, the findings were discordant, and support the relevance of establishing reference intervals for each region and specific population as recommended by the Clinical and Laboratory Standards Institute (CLSI) 15 .…”

“…Several laboratory parameters have specific reference values for men and women due to differences in anatomical structure, muscle mass or hormonal profile 13 . Specifically for the determination of platelet indices, there are contradictory reports about these differences 5, 13, 14…”

“…In this volume of the Brazilian Journal of Hematology and Hemotherapy, Ali et al analyzed the reference ranges of MPV, PDW, P-LCR and PCT according to gender, of 2356 apparently healthy individuals from a population of the United Kingdom 14 . In the study, individuals were found to have statistically significant differences in the reference range of MPV, P-LCR and PCT for men and women.…”

Large and small platelets—(When) do they differ?

“…These cell counters adopt or combine impedance and optical measurements of platelet dimensions 25 . The proportion of large cells is variable reflected by broad P‐LCR reference ranges between 17.6% and 47.0% in males and 17.8% and 47.8% in females 26 …”

“…25 The proportion of large cells is variable reflected by broad P-LCR reference ranges between 17.6% and 47.0% in males and 17.8% and 47.8% in females. 26 Instead, no standardized parameter to quantify small platelets exists. At least for scientific reasons a definition of a "platelet small cell ratio" would be desirable.…”