The diagnostic accuracy of Sysmex XN for identification of pseudothrombocytopenia using various thresholds for definition of platelet aggregation

Abstract

Introduction:The aim of this study was to investigate the diagnostic accuracy of the flag PLT-Clumps from the WNR/WDF and the PLT-F channels from Sysmex XN and to study how different cut-offs for investigation for pseudothrombocytopenia (PTCP) and the definition of platelet aggregation affected the diagnostic accuracy.Methods: A smear review was performed for samples with platelet count <150 Â 10 9 /L and samples flagged for platelet aggregation by Sysmex XN-20. The samples were investigated for platelet aggregation in 30 fields using 40Â objective. Findings were classified by size and quantity using two definitions of aggregation: the Norwegian quality improvement of laboratory investigations (Noklus) and the Groupe Francophone de'Hematologie Cellulaire (GFHC). The Q-values for the PLT-Clumps flag from the WNR/WFD channel and the PLT-F channel were compared with smear findings.Results: ROC analysis showed that the diagnostic accuracy of the PLT-clumps flags increased with increasing stringency of the definition of platelet aggregation and when only samples with thrombocytopenia were investigated. With the most stringent PTCP definitions, the diagnostic accuracy of the PLT-Clumps flag from PLT-F was very high (AUC 0.97-0.98) and markedly better than for WNR/WDF. Conclusion:The diagnostic accuracy of PLT-F from Sysmex XN-20 for identification of PTCP was very good and superior to the WNDR/WDF channel in samples with platelet count <150 Â 10 9 /L and a moderate to high number of aggregates in the smear. There is a need for a more precise definition of platelet aggregation.

The effect of oscillation depolymerization on ethylenediaminetetraacetic acid‐dependent platelet aggregation samples: A cross‐over study

“…The results showed that, under fixed time conditions, the oscillations affected the PLT, with higher oscillation speeds resulting in higher PLT values. An increase in PLT count can be used as an indicator of the disaggregation of clumped platelets, [14][15][16] and our results suggest that oscillations may have a disaggregating effect on clumped platelets. Blood cell analyzers mainly use sheath fluid resistance detection methods to detect platelet parameters, 17 which determine the PLT by counting blood elements within a specific size range, generating a platelet-volume histogram, and calculating the final data.…”

Developing and validating a highly sensitive platelet clump detection model for the Sysmex haematology analyser

“…To the best of our knowledge, this study is the first to apply a CNN algorithm to platelet clump detection using optical information from dedicated leucocyte channels, and the results showed that the CNN had a higher ability to detect platelet clumps than the XN-10 device's internal algorithm even under practical circumstances. Although the fluorescent platelet channel is also reported to have outstanding flagging performance detecting platelet clumping, 28 the regent for this channel is expansive and could not be tested on every CBC sample. However, the CNN could replace the current algorithm used in the Sysmex HA without requiring any additional device or reagent.…”