Abstract

Urine analysis is a routine test performed in clinical practice. Urine sediment analysis is a part of urinalysis that provides precious information to laboratory professionals. Manual review is an application which is time-consuming, as it is the gold standard for analysis. In this study, it was aimed to compare urine sediment analysis performance of the Sysmex UF-5000 flow cytometer with the manual Fuchs-Rosenthal counting chamber. From outpatient clinics, a total of 127 fresh urine samples were analyzed. Sysmex UF-5000 fluorescence flow cytometer was used for urine analysis and Fuchs-Rosenthal counting chamber was used for urine sediment analysis. Two methods were compared using Pearson correlation coefficient (r), Passing-Bablok regression analysis and Bland-Altman plot. CLSI Statis-Pro software version 3.0, Microsoft Excel 2010 and Analyse-it software version 3.80 (Analyse-it Software, Ltd., Leeds, UK) were used. A good correlation was observed between automated and manual white blood cell (WBC) counts in 71 urine samples (r = 0.988; y = 1.162x + 0.489; n = 127). The UF-5000 showed a significant proportional overestimation with the Passing-Bablok regression (95% CI slope: 1.110 to 1.226). Correlation between the counting chamber and UF-5000 was observed in 77 samples for red blood cell (RBC) counts (r=0.996; y=1.1x+0.75). This study showed that flow cytometry urinalysis is a promising area compared to the manual reference method. Urine analyzer automation is commonly used in clinical laboratories all over the world and is effective in reducing report time and workload.

Key words: Flow cytometer, urine analysis, Fuchs-Rosenthal chamber, UF-5000