Comparison of Body Fluid Cell Counting between Automate Hematology Analyzer Sysmex XT-4000i and Manual Microscopic Method.

Abstract

Objectives: To evaluate the comparison of body fluid cell count between automated hematology analyzer Sysmex XT-4000i and the gold standard manual microscope method using improved Neubauer hemocytometer or counting chamber.

Methods: Two thousand and fifty-three body fluid specimens, i.e., 85 of cerebrospinal fluid, 42 of synovial fluid, 51 of pleural fluid and 75 of ascitic fluid), were collected at the Hematology Laboratory, Department of Clinical Pathology, Faculty of Medicine Vajira Hospital. For counting red blood cells (RBC) and white blood cells (WBC) of body fluid specimens, the automatic Sysmex XT-4000i was used for analysis to compare with counting chamber, which is the gold standard method.

Results: Comparison of RBC and WBC counts of the two methods were analyzed by using Spearman’s rank correlation test (rs). The acceptable value of 218 of red blood cells count was in the range of more than 1,000 cells/μL (RBC count <1,000 cells/μL with the p-value = 0.037). The correlation of RBC count were rs = 0.857 (CSF), 0.748 (synovial fluid), 0.944 (pleural fluid) and 0.973 (ascitic fluid). The correlation of WBC count of 253 were rs = 0.950 (CSF), 0.936 (synovial fluid), 0.956 (pleural fluid) and 0.967 (ascitic fluid). RBC and WBC count by two methods were indicated that the correlation were high and in the same direction in any specimen except for synovial fluid. The correlation of differential polymorphonuclear cell (PMN) (rs=0.903) was better than mononuclear cell (MN) (rs=0.894). The background count, accuracy, precision, linearity and carryover for RBC and WBC count were found to be in the range. The correlation of counting WBC was better than RBC.

Conclusion: There is a good agreement for body fluid, red blood cells, white blood cells count and differential for PMN and MN examination were obtained between Sysmex XT-4000i and the manual gold standard method using counting chamber with the exception of the synovial fluid. With some limitations, the automate analyzer should not be used for body fluid cell counting, especially in the case of RBC less than 1,000 cells/ μL.