UriSed as a screening tool for presumptive diagnosis of urinary tract infection

Abstract

BackgroundAlthough a quantitative urine culture is essential for the final diagnosis of urinary tract infection, it is time-consuming and an expensive procedure. Effective screening tests would be a promising alternative to provide immediate results for the clinician and eliminate unnecessary culturing for most of the negative samples. The aim of this study was to evaluate the performance of an automated sediment analyzer (UriSed) as screening tool for presumptive diagnosis of urinary tract infection. MethodsWe studied 1379 fresh midstream clean-catch urine samples from children to elderly. All samples were submitted to automated sediment analysis (UriSed) and quantitative urine culture (CLED medium agar). ResultsThe sediment analyzer detected leukocyturia and/or significant bacteriuria with sensitivity of 97%, specificity of 59%, positive predictive value of 27%, negative predictive value of 99%, and accuracy of 64% at cutoff values of bacteria count ≥12.6 elements/hpf and WBC ≥6 cells/hpf. These data suggest a potential 52% reduction of unnecessary urine cultures. ConclusionThe UriSed seems to be an efficient tool for screening UTI with high sensitivity and low rate of false-negative results.