Sysmex XN-1000/2000 Technical Guide

Standard parameters and channel system

The XN series provides approximately 30 standard parameters, covering the core projects of routine hematological analysis. Standard parameters include WBC、NRBC#、NRBC%、RBC、HGB、HCT、MCV、MCH、MCHC、RDW-SD、RDW-CV、MicroR#、MacroR#、PLT、PDW、MPV、PCT、P-LCR、NEUT#、NEUT%、LYMPH#、LYMPH%、MONO#、MONO%、EO#、EO%、BASO#、BASO%、IG#、IG%。 Among them, the direct measurement and correction of WBC by NRBC are important features of the XN series, which can provide nucleated red blood cell information in each CBC analysis, reducing the need for manual microscopic review.

The WNR channel corresponds to XN-CBC applications, mainly used for white blood cell counting, eosinophils, and nucleated red blood cells. The WDF channel corresponds to the XN-DIFF application, providing 6 categories of white blood cells, including immature granulocytes. The WPC channel corresponds to the WPC application and is used to prompt abnormal white blood cell populations, such as abnormal lymphocytes, primitive cells, etc. For XN-20, HPC parameters can serve as additional value for assisting in determining the timing of peripheral blood stem cell collection. HPC and CD34 analysis have high comparability and can support rapid determination of the optimal collection timing.

In addition to standard parameters, the XN series also offers 16 optional parameters. Optional parameters include RET#、RET%、IRF、LFR、MFR、HFR、RET-He、RBC-He、Delta-He、HYPO-He、HYPER-He、PLT-O、PLT-F、IPF%、IPF#、HPC#/%。 These parameters can be configured and software activated according to the clinical needs of the laboratory. RET related parameters are used for monitoring red blood cell production, and Ret He helps distinguish functional iron deficiency from classical iron deficiency, and can be used for monitoring EPO or intravenous iron therapy. IRF stands for immature reticulocyte fraction, which can reflect the activity of red blood cell generation. PLT-F is a fluorescent platelet counting method that has a good correlation with CD61/41. IPF, which stands for immature platelet fraction, can be used for differential diagnosis of thrombocytopenic diseases and as an early predictor of platelet recovery.

Fluid analysis and special applications

The XN series can be equipped with a body fluid analysis mode, namely BF mode. This mode can perform fully automated analysis on samples such as cerebrospinal fluid, CAPD fluid, synovial fluid, and serum. Fluid analysis provides two categories, including monocyte population and polymorphonuclear cell population, which help distinguish between viral and bacterial infections. BF mode does not require additional reagents or special sample preparation, which can reduce the burden of manual microscopy. The report parameters include WBC-BF, MN #, MN%, PMN #, PMN%, TC-BF #, RBC-BF. For laboratories that need to process body fluid samples, BF mode can significantly improve standardization and turnover efficiency.

The RET channel is another important extension of the XN series. The parameters of reticulocytes include RET #, RET%, IRF, LFR, MFR, HFR, RET He, as well as RBC He, Delta He, HYPER He, etc. These indicators can be used for anemia identification, bone marrow hematopoietic function assessment, treatment monitoring, and transfusion management. Especially as a reticulocyte hemoglobin equivalent, Ret He can reflect iron utilization earlier and has practical value in the management of iron deficiency anemia, chronic disease anemia, and renal anemia.

The PLT-F channel uses fluorescence labeling for platelet counting, which has higher accuracy in low platelet samples. IPF% and IPF # can be used for the differentiation of thrombocytopenia, such as primary immune thrombocytopenia and aplastic thrombocytopenia. For patients undergoing autologous stem cell transplantation or chemotherapy, IPF can predict the recovery of platelet production. HPC parameters are used for peripheral blood stem cell collection management, which can assist in determining the collection timing and improving collection efficiency.

Performance specifications and sample size requirements

The whole blood throughput of XN-1000 and XN-2000 is about 100 samples/hour and 200 samples/hour, respectively. The sample suction volume varies depending on the mode: 88 μ L for whole blood mode, 70 μ L for pre dilution mode, 88 μ L for body fluid mode, and 190 μ L for HPC mode. When developing blood collection vessels, micro collection, and special project procedures in the laboratory, special attention should be paid to the HPC mode requiring a larger sample size to avoid unreliable results or repeated sampling due to insufficient samples.

In terms of quality control, the XN series supports three-level quality control materials for all parameters, as well as two-level body fluid quality control materials. For routine hematology projects, three-level quality control can cover low, medium, and high value ranges, which helps monitor precision and linearity. For fluid analysis, two-level quality control can meet the daily performance verification requirements. Engineers should establish quality control trend charts and regularly check reagent batch numbers, calibration status, laser signals, sheath flow pressure, and scatter plot distribution. If the quality control is out of control, priority should be given to investigating the expiration date of reagents, bottle stability, sample mixing, pipeline bubbles, flow chamber contamination, and software settings.