[Comparison Between Two Methods for the Measurement Reticulated Platelet and Their Clinical Significance--flow Cytometry (FCM) Method and IPF Method Using Automated Hematology Analyzer (XE-2000)]

Reticulated platelet (RP) is thought to be a useful marker for differential diagnosis and analysis of platelet kinetics in patients with thrombocytopenia. In this study, we compared two methods for the measurement of RP: flow cytometric (FCM) method and immature platelet fraction (IPF) method using automated hematology analyzer (XE-2000). There was a relatively good correlation between RP% measured by FCM method and IPF% measured by IPF method in patients with idiopathic thrombocytopenic purpura (ITP) (Y = 0.806X-0.050, r = 0.634, p < 0.001). We then measured RP% and IPF% in 61 patients with ITP and 27 patients with aplastic anemia (AA). For the differential diagnosis for ITP, the sensitivity (82%) and specificity (93%) of FCM method were better than those of IPF method (sensitivity 67% and specificity 63%). Our data demonstrate the significant difference between two methods by analyzing clinical samples in parallel.