Comparison of the Sysmex UF-100 Automated Urinalysis Analyzer and the Conventional Microscopic Method for Urinalysis

Urine microscopy is useful for detecting renal and urinary tract diseases. The microscopic techniques have several methodological steps that may cause inaccuracy and imprecision. The Sysmex UF-100 automated urinalysis analyzer has been introduced to analyze the unspun urine for improving the quality of results. In this study, we compared the UF-100 with the conventional microscopic technique. It was performed on urine samples collected from 104 outpatients at Siriraj hospital. Based on the precision analyses, the UF-100 was considered better than the conventional manual method. The correlations of the number of RBCs,WBCs, ECs, and casts detected from the two methods were found significant (r = 0.689-0.960). However,the number of RBCs, WBCs, ECs, and casts found in the UF-100 were 2.7, 2.5, 3.2 and 15.4 times higher than those in the conventional method respectively. The difference between the amount of RBCs, WBCs, ECs, and casts reported from the two methods could be attributed to the fact that all formed elements in a certain volume of urine were counted in the UF-100 whereas only those centrifuged sediments were included in the microscopic method. This study also showed that 60% of RBCs, 45% of WBCs, 30% of ECs, and 30% of casts in original urine still remained in the supernatant. We concluded that the UF-100 could be an alternative to the tedious conventional microscopic urinalysis because of its faster rate of analysis and more precise results. Key words : Urine Sediment, Sysmex UF-100