Evaluation of automated urine particle analyzer, UF-5000, as a screening tool to identify Gram stainability of urinal pathogens

Abstract

Urine smear (Gram stain) analysis is a rapid diagnostic method for urinary tract infection (UTI). At present, an automated urine analyzer with enhanced bacterial identification function is expected to be used as a screening tool. Here, we evaluated the performance of the automated urine particle analyzer UF-5000 (Sysmex), which has an enhanced function to identify bacterial Gram stainability (BACT-info), compared with conventional methods including Gram staining and quantitative bacterial culture. A total of 188 urine samples from suspected UTI patients were used and 179 were feasibly UTI. UF-5000 results were 83.2% in agreement with Gram staining results and 81.0% in agreement with culture results, whereas the agreement of Gram staining with culture results was 85.1%. Gram-negative results obtained with UF-5000 exhibited a high positive predictive value (93.3%) for both Gram staining and culture results. An insufficient judgement algorithm in UF-5000 may be responsible for some discordant results. UF-5000 using BACT-info shows great promise in screening for UTI pathogens.