A-122 Thorough Verification of Automated Hematology Equipment for Differential Cell Count Analysis in Whole Blood

Abstract Background Hematology analyzers (HA) represent a class of automated equipment that allows results to be revealed faster and more reliable. Among the tests with the highest volume is the complete blood count, which provides essential information for disease tracking and the monitoring of medical therapies. Therefore, the results generated by the HA constitute the basis for various medical interventions, and it is crucial that these results are analytically valid, with performance and suitability assurance. The study aimed to evaluate the analytical performance of the BC6000 automated hematology equipment (Mindray). Methods Precision, comparison, linearity and carryover tests were performed, as recommended by the manufacturer and in accordance with the parameters suggested by the SBPC (Brazilian Society of Clinical Pathology) guidelines. The 14 hematological parameters analyzed were: Erythrocytes, Hemoglobin, Hematocrit, MCV, MCH, MCHC, RDW, Platelets, Leukocytes, Neutrophils, Eosinophils, Basophils, Lymphocytes, and Monocytes. To evaluate precision and comparative analyses, the total allowable error (TEa) from the laboratory analytical quality (QAL) data or the biological variation criteria from the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) were used. For precision, three commercial control levels were measured in quintuplicate over 5 days. The statistical analysis considered 1/4 and 1/3 of the TEa for intra-assay and inter-run precision, respectively. For the comparative test, 20 to 25 samples were processed on both equipments: BC6000 and XN9100 (Sysmex). The acceptance criteria applied for the quantitative statistical evaluation was a correlation greater than 95%, and for qualitative analyses, a concordance greater than 75%. Linearity and carryover were assessed through serial dilution from samples, processed in duplicate (acceptance criteria of r²>0,99) and using samples with distinct values and according to the SBPC guidelines, respectively. The parameters analyzed were: Erythrocytes, Hemoglobin, Hematocrit, Platelets, and Leukocytes. The software EP Evaluator, version 12.4 was used for statistical analysis. Results Precision tests were passed with a 95% confidence interval for at least one control level for erythrocytes, hematocrit, MCH, and platelets. MCHC, MCH, and platelets precision tests were approved at one or more control levels using the manufacturer*s CV, while others were assessed using the TEa calculation. In the comparative test, erythrocytes, hemoglobin, hematocrit, platelets, leukocytes, neutrophils, eosinophils, lymphocytes, and monocytes passed according to the established quantitative criteria. MCV, MCH, MCHC, RDW, and basophils were approved by qualitative comparison using the Kappa criteria, considering the manufacturer*s reference values and/or results validated by the internal medical team’s evaluation. Regarding linearity, five analytes showed satisfactory results with an r² value greater than 0.99. Carryover testing for five analytes revealed expected results with a "Calc*d" limit of 3 standard deviations from the measurement of two consecutive low samples. Conclusion The verification of the analytical system showed satisfactory performance according to the established criteria. The variations found in the precision analysis were not statistically significant and were in accordance with the parameters determined by the QAL and/or the EFLM. For critical values, manual confirmation by microscopy is required, particularly for basophils. Data indicate the suitability of the BC6000 equipment for processing hematological tests.