Evaluation and comparison of automated hematology analyzer, flow cytometry, and digital morphology analyzer for monocyte counting.

INTRODUCTION: This study was aimed to evaluate monocyte counts on Sysmex XN-9000, Sysmex CyFlow Space System, and Sysmex DI60 and compare the performance of these systems with the reference optical microscopy (OM) assessment. METHODS: In all, 55 peripheral blood samples, collected in K3 EDTA tubes, were analyzed with XN-9000, CyFlow System (FlowDiff1 and 2), DI60, and OM. Within-run imprecision was carried out using normal samples. Data comparison was performed with Passing-Bablok regression and Bland-Altman plots. RESULTS: The within-run imprecision of monocyte count on XN, FlowDiff, OM, and DI60 ranged between 1.9% for FlowDiff 2 and 22.1% for DI60. The Passing-Bablok regression analysis of absolute count yielded slopes comprised between 0.93 (FlowDiff2 vs DI60) and 1.21 (DI60 vs OM), whereas the intercepts ranged between -0.002 (FlowDiff 1 vs FlowDiff 2) and 0.13 (FlowDiff1 and 2 vs DI60). Bland-Altman plots in absolute values yielded absolute bias comprised between -0.01 × 109 /L (FlowDiff 1 vs FlowDiff 2; DI60 vs OM) and 0.15 × 109 (XN-module vs DI60). CONCLUSION: The results of this analytical evaluation suggest that flow cytometry generates monocyte counts suitable for routine clinical use. OM or DI60 analysis may be useful for identifying morphologic abnormalities, but does not achieve a satisfactory level of accuracy for enumerating blood cells types such as monocytes, which are usually very low in peripheral blood.

ICSH Guideline for worldwide point-of-care testing in haematology with special reference to the complete blood count.

These guidelines provide information on how to develop and manage a point-of-care (POCT) service so that reliable haematology results are produced regardless of where the test is performed. Many of the issues addressed here are relevant to POCT within hospitals or health centres; however, the principles are equally applicable to care in the community and doctors' offices. Other aspects discussed in this guideline are the initiation of the service (including indications for and limitations of a POCT service), staff training, type of haematology equipment selected, the blood results, monitoring of quality, accreditation, safety and cost. Equipment selected should generate results that are comparable to those of the local reference laboratory. If a complete independent evaluation of the POCT device has not been performed, the purchaser should perform a local assessment according to the protocol in this document. A literature search should also be undertaken to find independent peer reviewed evaluations on POCT equipment. Often the ideals discussed here may not be achievable in some developing countries but long-term training and education of POCT workers needs to be supported and constantly kept on government agendas to reach the recommendations advised here. Users should interpret these recommendations for their particular POCT needs and setting.