Data from: Rapid and accurate detection of urinary pathogens by mobile IMS-based electronic nose: a proof-of-principle study

Urinary tract infection (UTI) is a common disease with significant morbidity and economic burden, accounting for a significant part of the workload in clinical microbiology laboratories. Current clinical chemisty point-of-care diagnostics rely on imperfect dipstick analysis which only provides indirect and insensitive evidence of urinary bacterial pathogens. An electronic nose (eNose) is a handheld device mimicking mammalian olfaction that potentially offers affordable and rapid analysis of samples without preparation at athmospheric pressure. In this study we demonstrate the applicability of ion mobility spectrometry (IMS) –based eNose to discriminate the most common UTI pathogens from gaseous headspace of culture plates rapidly and without sample preparation. We gathered a total of 101 culture samples containing four most common UTI bacteries: E. coli, S. saprophyticus, E. faecalis, Klebsiella spp and sterile culture plates. The samples were analyzed using ChemPro 100i device, consisting of IMS cell and six semiconductor sensors. Data analysis was conducted by linear discriminant analysis (LDA) and logistic regression (LR). The results were validated by leave-one-out and 5-fold cross validation analysis. In discrimination of sterile and bacterial samples sensitivity of 95% and specificity of 97% were achieved. The bacterial species were identified with sensitivity of 95% and specificity of 96% using eNose as compared to urine bacterial cultures. In conclusion: These findings strongly demonstrate the ability of our eNose to discriminate bacterial cultures and provides a proof of principle to use this method in urinanalysis of UTI.尿路感染（Urinary tract infection, UTI）是一类常见疾病，具有较高的发病率与显著的经济负担，同时占据临床微生物实验室日常工作量的重要组成部分。当前临床化学领域的即时检验依赖灵敏度欠佳的试纸条检测技术，仅能为尿路细菌病原体的检测提供间接且灵敏度不足的佐证。电子鼻（electronic nose, eNose）是一类模拟哺乳动物嗅觉功能的手持设备，有望在常压下无需样品预处理，即可实现低成本、快速的样本分析。本研究验证了基于离子迁移谱（ion mobility spectrometry, IMS）的电子鼻，可无需样品预处理，快速从培养皿的气态顶空样本中区分最常见的UTI病原体。我们共收集了101份培养样本，涵盖4种最常见的UTI致病菌：大肠埃希菌（E. coli）、腐生葡萄球菌（S. saprophyticus）、粪肠球菌（E. faecalis）以及克雷伯菌属（Klebsiella spp），同时设置了无菌培养皿作为对照样本。所有样本均采用搭载IMS检测单元与6个半导体传感器的ChemPro 100i型设备完成检测。数据分析采用线性判别分析（linear discriminant analysis, LDA）与逻辑回归（logistic regression, LR）两种方法完成，并通过留一法与5折交叉验证对分析结果进行了验证。在区分无菌与细菌样本的任务中，本方法实现了95%的灵敏度与97%的特异度；相较于尿液细菌培养的金标准结果，利用电子鼻识别细菌菌种的灵敏度为95%、特异度为96%。综上：本研究结果充分证明了所使用的电子鼻可有效区分细菌培养样本，为该方法应用于UTI的尿液分析提供了原理验证依据。