International Journal of Laboratory Hematology The Ofﬁcial journal of the International Society for Laboratory Hematology ORIGINAL ARTICLE INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY Initial performance evaluation of the UniCel Coulter cellular analysis system B. D. HEDLEY, M. KEENEY, I. CHIN-YEE, W. BROWN DxH 800 Department of Hematology, London Health Sciences Centre, London, ON, Canada Correspondence: Wendy Brown, Department of Hematology, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario, N6A 5W9 Canada. Tel.: +1 519 685 8300; Fax: +1 519 685 8360; E-mail. wendy.brown@lhsc.on.ca doi:10.1111/j.1751-553X.2010.01239.x Received 18 December 2009; accepted for publication 18 March 2010 Keywords Hematology analyzer, WBC, NRBC, platelet count, extreme leukocyto- sis, interference S U M M A R Y The Beckman Coulter UniCel DxH 800 is a hematology analyzer incorporating new electronic and mechanical design with advanced algorithm technology to perform CBC, white blood cell (WBC) differential, nucleated red blood cell (NRBC), and reticulocyte analysis. Evaluation of this instrument was performed in our 800-bed tertiary care hospital and specifically centered upon the correlation of WBC, NRBC, and platelet (PLT) enumeration when compared to a predicate analyzer, the Coulter LH 780, and flow cytometry (FCM) reference methods. Of particular interest were those samples with morpholog- ically confirmed interference and extreme leukocytosis (evaluated with respect to red blood cell parameter correction). The sample set (n = 272) consisted of morphologically normal and hematologically abnormal patients. Correlation of the WBC, PLT, and NRBC showed r2 values of 0.994, 0.985, and 0.910 for the DxH 800 vs. FCM, respectively. The presence of interfering particles did not affect the accuracy of the DxH 800 with respect to WBC counts. The DxH 800 showed accurate PLT and NRBC counts in the clinically signiﬁcant low range when compared to FCM. Compared to the LH 780, ﬂagging rates were signiﬁcantly reduced (NRBC ﬂag), or equivalent (WBC, PLT ﬂag) on the DxH 800. The DxH 800 demonstrated higher sensitivity and speciﬁcity for PLTs and NRBCs and achieved a lower NRBC false negative rate compared to the LH 780. The UniCel DxH 800 represents a significant improvement to previous impedance analyzers in accurately detecting the presence of NRBCs at counts >1/100 WBC. Furthermore, it provides accurate PLT and WBC counts in the presence of interference and improved NRBC flagging efficiency when compared to the LH 780. Correction of red blood cell parameters is appropriate and accurate in cases of extreme leukocytosis. Re-use of this article is permitted in accordance with the Terms and Conditions set out at http://wileyonline library.com/onlineopen#OnlineOpen_Terms 2010 Blackwell Publishing Ltd, Int. Jnl. Lab. Hem. 2011, 33, 45–56 I N T R O D U C T I O N The accurate automated enumeration and identiﬁca- tion of platelets (PLTs), white blood cells (WBCs), and 45