Comparison of four automated hematology analyzers

To compare four automated hematology analyzers for efficiency and sensitivity.

Four automated hematology analyzers were compared in a side by side study: Bayer ADVIA 120 (Bayer Diagnostic Division, Tarrytown, NY), Beckman Coulter GEN S (Beckman Coulter, Brea, CA), Abbott CELL DYN 3500 and CELL DYN 4000 (Abbott Diagnostics, Santa Clara, CA). 164 specimens were analyzed for cell counts, indices, and the automated WBC differential (DLC). Tallies were kept of all interventions, defined as any parameter necessitating examination of a stained blood smear by a clinical laboratory scientist. A 400-cell manual differential was performed on each specimen and used as the reference to prepare truth tables for each type of WBC.

Specimens comprised regular runs from this tertiary care teaching hospital. These included inpatients, outpatients, and oncology patients, including bone marrow transplant patients.

Results from the truth tables were used for calculating sensitivity and efficiency for each analyzer. Each DLC parameter was analyzed for variance using the one-way ANOVA test.

No intervention was required for 103 of 164 specimens for the CELL DYN 3500; the ADVIA gave 70 reportable DLCs without intervention, the GEN S provided 91 and the CELL DYN 4000 resulted in 117 of 164 DLCs without intervention. Agreement or efficiency was 65% for the CELL DYN 3500, 41% for the ADVLA, 58% for the GEN S, and 79% for the CELL DYN 4000. Sensitivity was 67% for the CELL DYN 3500, 86% for the ADVIA, 76% for the GEN S, and 71% for the CELL DYN 4000. Probability of significant variation was as follows for each parameter: % neutrophil 0.8747, % lymphocyte 0.8830, % monocyte 0.0296, % eosinophil 0.7903, and % basophil <.0001.

The analyzers tested were acceptable for routine laboratory work. Selection would depend on individual need with respect to sensitivity and efficiency. The clinical significance of disagreement between the DLC and the manual differential remains to be determined.