RESUMO
OBJECTIVE: Although the microscopic manual count is considered the standard method for NRBC enumeration, modern hematology analyzers can perform this task automatically with reliable accuracy and efficiency. This study aims to evaluate the diagnostic performance of the Sysmex XN hematology analyzer and to construct the optimal workflow for accurate and efficient NRBC reporting. METHODS: Specimens containing different levels of NRBC were included. Analytical performance was evaluated via method comparison with flow cytometry (FCM) and manual count (MC). Clinical sensitivity was analyzed by ROC analysis using manual count as the standard method. RESULTS: Correlation study of %NRBC with FCM and MC demonstrated an r value of 0.925 (95% CI 0.905 to 0.942) and 0.990 (95% CI 0.987 to 0.992) with a mean difference of -0.8 (95%CI: -6.7 to +5.0) and +0.50 (95% CI: -6.7 to +7.7), respectively. When the automated NRBC count was equal to zero and >0.07 × 109 /L, the false-negative rate and false-positive rate were 100%, respectively; hence, manual slide review could be omitted. A false-positive rate of 72.7% was noted in specimens containing NRBC count less than 0.07 × 109 /L. CONCLUSION: The Sysmex XN can help improve the efficiency of NRBC enumeration owing to its accuracy, rapidity, and automation. However, further studies are required to improve the accuracy of detection in specimens containing a very low level of NRBC.
