Evaluation of Five Automated Urine Analyzers as Screening Instruments for Enhancing Diagnostic Efficiency in Urinary Tract Infection

Abstract

진단적 효율을 장비로서의 자동화 ABSTRACT Background: Although urine culture is considered a reference standard for the diagnosis of urinary tract infection (UTI), it is time-consuming, labor-intensive, and expensive. Here, we evaluated the performance of five recent automated urine analyzers for UTI diagnosis. Methods: For the 510 specimens analyzed, the criterion for ‘ significant bacteriuria’ was defined as ≥ 10 4 CFU/mL in the inoculated plate for all specimens or ≥ 10 3 CFU/mL for specimens from patients using a Foley catheter or with urinary symptoms. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of UTI were analyzed using indicators individually, in different combinations, or with various cut-off values. Results: Seventy-one specimens (13.9%) exhibited ‘ significant bacteriuria’. In the receiver operating characteristics curve analysis, UF-5000 (Sysmex Corp., Japan) showed the highest area under the curve values for both males and females (0.876 and 0.846, respectively). The PPVs for specimens from males with all indicators positive increased up to 100% after adjusting the cut-off values. NPVs for specimens with all indicators negative were 94.3%– in males and 78.1%–93.8% in females after adjusting the cut-off values. Conclusion: As a rapid and accurate diagnostic tool, urine sediment analyzers can be valuable for UTI diagnosis by reducing unnecessary culture and can help clinicians determine a treatment plan. The Cobas ® u701 and URiSCAN® PlusScope did not display the quantitative bacterial counts when our experiment was conducted. The iQ ® 200SPRINT provided ASP values instead of bacterial counts.