Performance evaluation of the automated nucleated red blood cell enumeration on Sysmex XN analyser

Summary Introduction Presence of peripheral blood nucleated red blood cell ( NRBC ) is associated with pathological conditions and leads to the overestimation of white blood cell count in automated haematology analysers ( HA ). The authors evaluated NRBC enumeration by a new HA Sysmex XN ( XN ) to demonstrate the precision and comparability to manual count ( MC ) at the various NRBC values. Methods Specimens with initially NRBC positive were included. For precision assessment, 8 levels of NRBC s were repeatedly analysed. For comparison study, 234 specimens were analysed by both XN and MC . Results For precision study, the percentage of coefficient of variation ranged from 14% to 45.6% and 1.2% to 4.4% for MC and XN , respectively. For comparison study between XN and MC , NRBC s ranged from 0% to 612.5%. Regression analysis demonstrated an r 2 of 0.98. The mean bias of 14.1% with 95% limits of agreement between –48.76% and 76.95% was found. The NRBC counts from XN appeared to be more in accordance with MC when the NRBC s were lower than 200% with the concordance rate of 94.2%. Conclusion The automated NRBC enumeration by XN was precise and could replace the traditional MC , especially for the specimens with NRBC s lower than 200%.