Platelet Count Pitfalls Between Routine and Advanced Techniques

Background: Precise quantification of platelet counts is a fundamental aspect of clinical hematology, pivotal in diagnosing and managing conditions such as thrombocytopenia and thrombocytosis. However, inconsistencies in platelet measurements across various automated hematology analyzers present significant challenges, potentially compromising the reliability of results. This variability is especially critical when platelet counts inform urgent clinical interventions, including the administration of platelet transfusions. Aim: The present study evaluated the accuracy of Sysmex XN-350 and Mindray in comparison to flow cytometry, the gold standard for platelet counting. Methods: 120 blood samples were categorized into thrombocytopenic, thrombocytosis, and normal groups. Platelet counts were measured using Sysmex XN-350, Mindray BC-720, and flow cytometry. Statistical analyses, including correlation coefficients, Bland-Altman plots, and repeated measures ANOVA, were employed to assess agreement and differences among the methods. Results: The study revealed significant discrepancies in platelet counts among the devices. Sysmex XN-350 consistently overestimated platelet counts compared to flow cytometry, particularly at higher counts, with a mean difference of 176.76 ± 358.51. Mindray BC-720 demonstrated greater agreement with flow cytometry, with a mean difference of 60.062 ± 119.67 and a stronger correlation (r = 0.972). Bland-Altman analysis showed that Sysmex exhibited substantial overestimation at higher platelet counts, while Mindray maintained consistency within clinically relevant ranges. Conclusions: Mindray BC-720 outperformed Sysmex XN-350 in terms of agreement with flow cytometry, especially in the thrombocytopenic and normal ranges. These findings highlight the importance of validating automated hematology analyzers against advanced techniques like flow cytometry to ensure precision in platelet enumeration.