Evaluation of a phenotypic, point-of-care solution for the detection and quantitative antibiotic susceptibility testing for lower Urinary Tract Infection

BackgroundUrinary tract infections (UTIs) are one of the most common bacterial infections seen in primary care. The current standard for diagnosis is microbiological culture and antibiotic sensitivity testing of a mid-stream urine sample; however, this technique is costly, labour intensive and typically takes 2-3 days to yield a result. Study design and ObjectiveThis is a nonexperimental cross-sectional study. The aim of this study was to evaluate the efficacy of U-treat, a bioluminescent approach for rapid detection of bacteriuria and quantitative determination of the antimicrobial susceptibility profiles of uropathogens in clinical urine specimens - in under an hour. MethodThe evaluation was carried out in two UK-based Medical Centres using urine samples from patients presenting with symptoms of a UTI (n=249). The U-treat technology is a two test, two reagent process. Test 1 detects the presence of a bacterial UTI > 104 bacteria/mL (5-10 minutes). Test 2 produces quantitative antibiotic susceptibility (<50 minutes). Only urine samples testing positive for bacteria in Test 1 underwent Test 2 (n=82). U-treat results were compared retrospectively against reference laboratory culture and sensitivity findings. The influence of the technology on patient treatment outcomes was also analysed. ResultsRelative to reference laboratory analysis, Test 1 showed a sensitivity of 97.1% and specificity of 92.0%. (PPV: 89.3%; NPV: 97.8%). Test 2 produced an overall sensitivity (measurement of true susceptibility) of 94.1% (Predictive value: 96%) and an overall specificity (measurement of true resistance) of 90.5% (Predictive value 86.4%). Analysis of treatment data demonstrated that had the physicians had access to U-treat results at the point of care, the percentage of patients treated successfully would have risen from 68.3% to 92.7%. ConclusionU-treat represents the first technology, world-wide, capable of providing UTI treatment data to physicians at the point of care, in less than 60 minutes.