Evaluation of cell count and classification capabilities in body fluids using a fully automated Sysmex XN equipped with high-sensitive Analysis (hsA) mode and DI-60 hematology analyzer system

Abstract

The XN series automated hematology analyzer has been equipped with a body fluid (BF) mode to count and differentiate leukocytes in BF samples including cerebrospinal fluid (CSF). However, its diagnostic accuracy is not reliable for CSF samples with low cell concentration at the border between normal and pathologic level. To overcome this limitation, a new flow cytometry-based technology, termed “high sensitive analysis (hsA) mode,” has been developed. In addition, the XN series analyzer has been equipped with the automated digital cell imaging analyzer DI-60 to classify cell morphology including normal leukocytes differential and abnormal malignant cells detection. Using various BF samples, we evaluated the performance of the XN-hsA mode and DI-60 compared to manual microscopic examination. The reproducibility of the XN-hsA mode showed good results in samples with low cell densities (coefficient of variation; % CV: 7.8% for 6 cells/μL). The linearity of the XN-hsA mode was established up to 938 cells/μL. The cell number obtained using the XN-hsA mode correlated highly with the corresponding microscopic examination. Good correlation was also observed between the DI-60 analyses and manual microscopic classification for all leukocyte types, except monocytes. In conclusion, the combined use of cell counting with the XN-hsA mode and automated morphological analyses using the DI-60 mode is potentially useful for the automated analysis of BF cells.

Lack of harmonization in high fluorescent cell automated counts with body fluids mode in ascitic, pleural, synovial, and cerebrospinal fluids

“…The XN‐BF module uses fluorescent flow cytometry with hydrodynamic focusing for generating total count (and classification) of RBC, WBC (XN‐WBC‐BF), and TC (XN‐TC‐BF) in BF samples. Briefly, a total volume of 88 µL is used for each BF sample . In the BF‐mode, the combination of laser side scatter (SSC), forward scatter (FSC), and fluorescence analysis (SFL) allows classifying nucleated cells, which are clustered in the WDF‐scattergram according to their complexity ( x ‐axis), size ( z ‐axis), and nucleic acid content ( y ‐axis).…”

“…Cell counting and classification in body fluids (BFs; ascitic [AF], pleural [PF], synovial [SF], and cerebrospinal [CSF]) has become very popular in recent times due to enhanced availability of new commercial instrumentation . Carried out using suitable analyzers, automated cell count can now be regarded as a useful screening, since is adequately precise, may substantially reduce the turnaround time (TAT), is available 24 hours a day, and allows better standardization of the analytical process …”

“…Although all hematological analyzers (also referred to as “hemocytometers”) equipped with the BF‐mode can generate both quantitative and qualitative measures, these parameters differ among the various commercial analyzers, being mostly instrument‐dependent. Quantitative parameters may include total cell count (TC), leukocyte count (WBC) and, sometimes, differential cell count capable to discriminate between polymorphonuclear (PMN) and mononuclear (MN) leukocytes . The two hematological analyzers of Sysmex XN series (Sysmex, Kobe Japan) and the Mindray BC‐6800 (Mindray, Shenzhen, China) are equipped with a BF‐mode channel dedicated to cell count and classification, which is based on optical fluorescence reading, selective lysis of red blood cells (RBCs), along with specific hardware and fluidics.…”

“…The XN‐module in BF mode (XN‐BF) provides the following diagnostic parameters: TC (XN‐TC‐BF), WBC (XN‐WBC‐BF), PMN (XN‐PMN‐BF), MN (XN‐MN‐BF), and high fluorescent cells (XN‐HF‐BF) counts, as well as additional research parameters such as neutrophil (XN‐NE‐BF), lymphocyte (XN‐LY‐BF), monocyte (XN‐MO‐BF), and eosinophil (XN‐EO‐BF) counts . The BC‐6800 in BF mode (BC‐BF) generate TC (BC‐TC‐BF), WBC (BC‐WBC‐BF), PMN (BC‐PMN‐BF), MN (BC‐MN‐BF), and high fluorescent cells (BC‐HF‐BF) counts, along with other research parameters such as neutrophil (BC‐NE‐BF) and eosinophil (BC‐EO‐BF) counts .…”

“…The BC‐6800 in BF mode (BC‐BF) generate TC (BC‐TC‐BF), WBC (BC‐WBC‐BF), PMN (BC‐PMN‐BF), MN (BC‐MN‐BF), and high fluorescent cells (BC‐HF‐BF) counts, along with other research parameters such as neutrophil (BC‐NE‐BF) and eosinophil (BC‐EO‐BF) counts . For both XN‐BF and BC‐BF modes, the number of cells classified as HF‐BF is significantly correlated with the presence of mesothelial and/or various neoplastic cells . According to the origin of the BF, the presence of a variable number of cells classified as HF‐BF can then suggest microscopic revision of the sample …”