[Evaluation of Immature Platelet Fraction Measurements Using an Automated Hematology Analyzer, Sysmex XN]

The immature platelet fraction (IPF%) is a parameter for the automatic quantification of reticulated plate- lets and is considered to reflect platelet production. We evaluated IPF% measurements using an automated analyzer, the Sysmex XN. We measured the platelet counts and the IPF% values in 35 healthy subjects and 275 patients with various diseases using both the XN analyzer and a conventional analyzer, the Sysmex XE. Significant correlations in the platelet count and the IPF% were observed between the XN results and the XE results. In the same samples, significant inverse correlations were observed between the platelet count and the IPF% in both the XN and XE results. The coefficient of variation values for the platelet count and the IPF% measurements obtained using the XN analyzer were lower than those obtained using the XE ana- lyzer. In patients who had undergone hematopoietic stem cell transplantation, the IPF% measurements obtained using the XN analyzer increased several days before platelet recovery. IPF% measurements performed using the XN analyzer are adequate for clinical use. This parameter may be a useful marker for the prediction of platelet recovery. [Original].