Performance Evaluation of the Latest Fully Automated Hematology Analyzers in a Large, Commercial Laboratory Setting: a 4-way, Side-by-side Study

Gamma-Dynacare is a Canadian-based community laboratory partnership formed in the mid-1990s through the merger of 3 prominent Ontario medical diagnostic laboratories. Laboratory Corporation of America acquired an interest in the GD partnership in mid 2002. We service more than 10,000 community-based Canadian clinicians, hospital partners, and private clients with an integrated customer-focused system that includes specimen collection, transportation, and results reporting services. With more than 1,700 highly qualified medical, technical, and support staff and a network of laboratories, Gamma Dynacare aims to be at the forefront of technological innovation to better service the clinician base and ultimately deliver better patient care. We were looking for a hematology analyzer that would allow. (1) standardization throughout Ontario in our 4 largest sites and (2) better performance to effectively handle aged samples and minimize slide review. To select the best, most productive hematology analyzer for our environment, it was decided to perform a side-by-side comparison of the top hematology analyzers from Abbott (Cell-Dyn 3500), Beckman Coulter (LH 750), Bayer (Advia 120), and Sysmex (XE 2100), utilizing the same samples. CBC, differential and reticulocyte parameters were all evaluated according to CLSI (formerly NCCLS) and established hematology analyzer evaluation guidelines. We assessed each analyzer for precision, linearity, carryover, stability, differential capabilities, slide review rates, and throughput (clean bench studies). Two hundred samples were assessed for differential and morphology flagging on each analyzer using the reference 400 cell manual differential for comparison. Throughput was assessed by analyzing 700 consecutive samples representative of our workload mix. Stability studies at 24 hours showed that the Beckman Coulter LH 750 was least affected by EDTA, effect with minimal changes in the mean corpuscular volume (MCV) and hematocrit. Both the Bayer Advia 120 and Sysmex XE 2100 showed an elevation of the MCV (up to 5 fL) and Hematocrit over the 24 hours. Analysis of the 200 randomly selected patient samples showed that, while the false-negative rates on each of the instruments were comparable, there were significant differences in the false-positive rates. This has important implications for slide review rates. For our specimen mix, the Sysmex XE 2100 had the highest false-positive rate (15%), followed by the Cell-Dyn 3500 (8%), Advia 120 (6.5%) and the Beckman Coulter LH 750 (1.5%). Reticulocyte analysis performance was observed to be satisfactory with the Beckman Coulter LH 750, Cell-Dyn 3500, and XE 2100, while the Bayer Advia 120 showed a decrease in retic values after 12 hours. In conclusion, many laboratories will not be able to perform a 4-way evaluation such as described here due to time, space, and resource constraints. For our laboratories, result quality, sample stability performance, slide review rates, and efficiency were the primary criteria in selection of the most suitable hematology analyzer. Our 4-way evaluation resulted in selection of the Beckman Coulter LH 750 for Gamma-Dynacare Laboratories because it enabled the lowest slide review rate and handled aged samples better than the other analyzers.