Reporting Sysmex XN Absolute Neutrophil Count in Samples with Leukocyte Analyzer Flagging

Abstract

Abstract Objective To provide faster laboratory data reporting, we evaluated the accuracy of Sysmex XN (Sysmex Inc, Kobe, Japan) absolute neutrophil count (ANC) in the presence of analyzer flagging. Methods Sysmex XN and manual microscopy ANC were compared with 80 autovalidated control specimens and with 280 study specimens with analyzer flagging regarding immature granulocytes (IG) >3% or other leukocyte abnormalities. Specimens with ambiguous neutrophil clusters were excluded. Results A slight positive overall method bias was seen for Sysmex XN compared to manual microscopy (n = 280), 0.025 (95% confidence interval [CI], –0.023 to 0.069) × 109/L. With IG > 10% (n = 123) the bias was larger, but not clinically significant, 0.17 (95% CI, 0.060–0.25) × 109/L. No clinically significant difference was seen in neutropenic (ANC < 1.5 × 109/L) specimens (n = 91), 0.070 (95% CI, –0.013 to 0.14) × 109/L. Conclusion These data indicate that Sysmex XN ANC can be reported in the presence of certain analyzer flagging to improve patient care.