Evaluation of the fully automated hematological analyzer Sysmex XE-5000 for flow cytometric analysis of peritoneal fluid.

Although microscopy still represents the gold standard for cytometric analysis of peritoneal fluids, automated flow cytometry may improve throughput and accuracy. We evaluated the performance of total nucleated cell (TNC), white blood cell (WBC), polymorphonuclear cell (PMN), and mononuclear cell (MONO) counts of Sysmex XE-5000 on peritoneal fluids. The imprecision was excellent, being always lower than 11%, whereas linearity studies yielded correlation coefficients of 1.00 for all parameters. The carryover was always lower than 0.2%. The comparison between XE-5000 and microscopic analysis of 117 ascitic fluids yielded correlation coefficients always greater than 0.96, with mean biases <11/µL. The diagnostic accuracy versus manual microscopy was greater than that of XE-2100, especially at thresholds for septic ascites (100 versus 98% for ≥500 WBC/µL; 98 versus 93% for ≥250 PMN/µL). The correlation with manual microscopy for macrophages and mesothelial cell count was also higher for XE-5000 than for XE-2100 (0.63 versus 0.55). The results of this evaluation show optimal performance of XE-5000 for routine analysis of ascitic fluids, which are combined with the advantages of automated analysis such as high throughout, shortened turnaround time, no need of sample preparation and trained staff, reduced sample volume, and less likelihood of transcriptional errors.

Evaluation of white blood cell count in peritoneal fluid with five different hemocytometers.

OBJECTIVES: Evaluation of automated flow cytometric analysis of white blood cell (WBC) count in peritoneal fluids. METHODS: One hundred peritoneal fluids were analyzed with manual microscopy, Sysmex XE-2100 and XE-5000, Siemens Advia 2120, Mindray BC-6800, Abbott Sapphire. RESULTS: High correlations (0.978 to 0.999) and modes biases (-132 to 80 WBC/mm(3)) were found. Agreement at septic peritonitis cutoff ranged between 96% and 99%. CONCLUSIONS: These hemocytometers display acceptable performance for WBC screening in peritoneal fluids.

Identification of spurious hemolysis in anticoagulated blood with Sysmex XE-2100 and Siemens Advia 2120.

BACKGROUND: Various degrees of hemolysis might occur during collection, processing and storage of blood bags or blood tubes for hematological testing. In both circumstances, the identification of hemolysis is challenging since the centrifugation process is not required. The aim of this study was to identify simple hematological parameters that would help identify the presence of hemolysis in anticoagulated blood. METHODS: Twenty tubes containing K2EDTA anticoagulated blood were randomly selected from outpatient samples and divided in two aliquots. The former was immediately analyzed, whereas the latter was subjected to mechanical hemolysis by aspirating whole blood two times through a very fine needle to generate mechanical hemolysis. Both aliquots were tested on Advia 2120 and Sysmex XE-2100. RESULTS: The double aspiration of the blood through the fine needle caused a remarkable hemolysis with significant decrease of red blood cell (RBC) count (-17 +/- 11%; p < 0.01), hematocrit (-18 +/- 12%; p < 0.01) and reticulocytes (-24 +/- 13%; p < 0.01), but not of hemoglobin, white blood cell or platelet counts. A remarkable increase of immature platelet fraction (IPF) on XE-2100 and RBC ghosts on Advia 2120 was observed in the hemolyzed samples, whereas RBC fragments did not vary significantly. A significant correlation was also observed between hemolysis and reticulocyte count (r = 0.823; p < 0.01), IPF (r = -0.502, p = 0.024) and RBC ghosts (r = -0.711; p < 0.01). Receiver Operating Characteristic (ROC) curve analysis demonstrated a good performance of both IPF and RBC ghosts (i.e., AUCs 0.91 and 0.96, respectively) for distinguishing non-hemolyzed from hemolyzed specimens. CONCLUSIONS: The absolute values of both IPF and RBC ghosts perform efficiently for distinguishing hemolyzed from non-hemolyzed specimens, although neither reached 100% sensitivity and specificity. Nevertheless, the demonstration that both parameters significantly increase after hemolysis can be reliably used to distinguish hemolyzed from non-hemolyzed blood.