Diagnostic efficiency of the Sysmex XN WPC channel for the reduction of blood smears

Abstract Background Several small studies showed that the WPC (white precursor cell) channel in the Sysmex haematology analyser for leukocyte differentiation analysis leads to a significant reduction of microscopic blood smears. We determined the added value of the WPC channel for blood smear reduction in a large teaching hospital and whether this reduction was cost-effective and save. Methods Retrospectively, for 7850 leukocyte differentiation orders the percentage of samples resulting in a WPC analysis and the outcomes of the WPC analysis were analysed and compared with the blood smear results. Results WPC analysis resulted in a 12% reduction of blood smears, which is much lower than observed in other studies. This means 3–4 blood smears/day less of a total of 28 smears/day at the expense of missing 14 patient samples with pathology (blasts or abnormal lymphocytes) in a 9 weeks period. The estimated total costs of WPC analysis per year was more than the reduction in costs due to less blood smear reviews. Conclusions In a large teaching hospital, the small reduction in blood smears by the WPC channel does not outweigh the costs and the slight reduction in sensitivity for pathology.