Leukocyte Differential on Hematology Analyzer Compared and Evaluated

A complete blood count (CBC), also known as a full blood count (FBC), is a set of medical laboratory tests that provide information about the cells in a person's blood. The CBC indicates the counts of white blood cells, red blood cells and platelets, the concentration of hemoglobin, and the hematocrit (the volume percentage of red blood cells).

Different hematology analyzer models use various principles to measure the complete blood count (CBC) and leukocyte differential for routine tests in clinical laboratories. The accuracy performance of a hematology analyzer is evaluated using the manual differential leukocyte (Manual-Diff) on blood wedge film (Wedge-Diff) as the traditional reference method.

Clinical Laboratorians at the Kindai University Hospital (Osakasayama, Japan) selected for method comparison, 598 clinical samples and 46 healthy volunteer samples. All samples were collected in tubes containing K2-EDTA. The blood collection tubes, blood collection procedure, and mixing procedure were according to described methods. For method comparison between the three analyzers, 388 clinical samples were used. Blood films were stained with May-Giemsa.

The automated hematology analyzer Celltac G (Nihon Kohden, Tokyo, Japan) was designed to improve leukocyte differential performance. The two comparative hematology analyzers (CAAs) used were XN-9000 (Sysmex, Kobe, Japan) and CELL-DYN Sapphire (Abbott Diagnostics, Santa Clara, CA, USA). In manual differential, two kinds of automated slide makers were used: the Sysmex SP-10 for wedge technique and SPINNER-2000 (Lion-Power, Komatsu, Japan) for spinner technique. The immunophenotypic leukocyte differential reference method (FCM-Ref) was selected, and a flow cytometer Navios (Beckman-Coulter, Indianapolis, IN, USA) was used.

The investigators reported that the Celltac G showed sufficient comparability with the CAAs for each leukocyte differential counting value up to 40.87 × 10⁹/L, and sufficient comparability with FCM-Ref for each leukocyte differential percentage at 0.4–78.5. The identification ratio of the FCM-Ref in CD⁴⁵-positive cells was 99.7% (99.4% to 99.8%). Differences were found between FCM-Ref/Celltac G/XN-9000/Spinner-Diff and Wedge-Diff for monocytes and neutrophils. The appearance ratio of smudge cells on wedge and spinner film was 12.5% and 0.5%.

The authors concluded that the Celltac G hematology analyzer's leukocyte differential showed adequate accuracy compared with two comparative hematology analyzers, reference flow cytometry method, and two manual methods and was considered suitable for clinical use. The study was published on June 12, 2021 in the Journal of Clinical Laboratory Analysis.

Related Links:
Kindai University Hospital
Nihon Kohden
Sysmex
Abbott Diagnostics
Lion-Power
Beckman-Coulter