Age-Specific Cutoffs of the Sysmex UF-1000i Automated Urine Analyzer for Rapid Screening of Urinary Tract Infections in Outpatients

• Published in: Annals of laboratory medicine 2019, 39(3), , pp.322-326
• Main Authors: Kim, Hyunji, Kim, Hye Ryoun, Kim, Tae Hyoung, Lee, Mi Kyung
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age Factors; Aged; Anti-Bacterial Agents - pharmacology; Area Under Curve; Bacteria - isolation & purification; Brief Communication; Child; Child, Preschool; Gram-Negative Bacteria - drug effects; Gram-Negative Bacteria - isolation & purification; Gram-Positive Bacteria - drug effects; Gram-Positive Bacteria - isolation & purification; Humans; Leukocyte Count; Middle Aged; Outpatients; Retrospective Studies; ROC Curve; Urinalysis - instrumentation; Urinalysis - methods; Urinary Tract Infections - diagnosis; Young Adult; 병리학
• ISSN: 2234-3806; 2234-3814
• DOI: 10.3343/alm.2019.39.3.322

We investigated the usefulness of age-specific cutoffs for screening of urinary tract infections (UTIs) in Korean outpatients, using the automated urine analyzer UF-1000i (Sysmex, Kobe, Japan). We retrospectively reviewed outpatient medical records. Urine samples of 7,443 outpatients from January 2010 to December 2017 were analyzed using urine culture and UF-1000i. ROC curves were calculated for each UF-1000i parameter based on the culture results. There were 1,398 culture positive samples, 5,774 culture negative samples, and 271 contaminated samples. UF-1000i had an area under the curve of ≥0.9 in outpatients >15 years. The appropriate cutoffs, which are the sum of bacterial (B-A-C) and white blood cell (WBC) counts, were 297.10/μL (15-24 years), 395.65/μL (25-44 years), 135.65/μL (45-64 years), 67.95/μL (65-74 years), and 96.5/μL (≥75 years). B-A-C and WBC counts differed among the three most frequently identified bacteria ( , , and ). The UF-1000i system is useful for applying age-specific cutoffs to screen for UTIs, thereby preventing antibiotic abuse and reducing antibiotic resistance. Future studies can explore how its B-A-C and WBC counts can facilitate selection of empirical antibiotics by distinguishing between gram-positive and gram-negative bacteria.