Torres-Sangiao Eva, Lamas Rodriguez Brais, Cea Pájaro María, Carracedo Montero Raquel, Parajó Pazos Noelia, García-Riestra Carlos
Grupo Escherichia coli, Fundación Instituto de InvestigaciónSanitaria (FIDIS), Hospital Clínico Universitario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain.
Clinical Microbiology Lab, University Hospital Marqués de Valdecilla, 39008 Santander, Spain.
Antibiotics (Basel). 2022 May 15;11(5):663. doi: 10.3390/antibiotics11050663.
Urinary tract infections (UTIs) are the most common infectious diseases in both communities and hospitals. With non-anatomical or functional abnormalities, UTIs are usually self-limiting, though women suffer more reinfections throughout their lives. Certainly, antibiotic treatment leads to a more rapid resolution of symptoms, but also it selects resistant uropathogens and adversely affects the gut and vaginal microbiota. As uropathogens are increasingly becoming resistant to currently available antibiotics, it could be time to explore alternative strategies for managing UTIs. Rapid identification and antimicrobial susceptibility testing (AST) allow fast and precise treatment. The objective of this study was to shorten the time of diagnosis of UTIs by combining pathogen screening through flow cytometry, microbial identification by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS), and the VITEK 2 system for the direct analysis of urine samples. First, we selected positive urine samples by flow cytometry using UF5000, establishing the cut-off for positive at 150 bacteria/mL. After confirming the identification using MALDI-TOF MS and filtering the urine samples for , we directly tested the AST N388 card using VITEK 2. We tested a total of 211 from urine samples. Cefoxitin, ertapenem, imipenem, gentamicin, nalidixic acid, ciprofloxacin, fosfomycin, and nitrofurantoin had no major important errors (MIE), and ampicillin, cefuroxime, and tobramycin showed higher MIEs. Cefepime, imipenem, and tobramycin had no major errors (ME). Fosfomycin was the antibiotic with the most MEs. The antibiotic with the most minor errors (mE) was ceftazidime. The total categorical agreement (CA) was 97.4% with a 95% CI of (96.8-97.9). The direct AST from the urine samples proposed here was shorter by one day, without significant loss of sensibility regarding the standard diagnosis. Therefore, we hypothesize that this method is more realistic and better suited to human antibiotic concentrations.
尿路感染（UTIs）是社区和医院中最常见的传染病。在没有解剖学或功能异常的情况下，尿路感染通常是自限性的，不过女性在一生中更容易再次感染。当然，抗生素治疗能使症状更快缓解，但也会筛选出耐药的尿路病原体，并对肠道和阴道微生物群产生不利影响。由于尿路病原体对目前可用的抗生素越来越耐药，可能是时候探索管理尿路感染的替代策略了。快速鉴定和抗菌药敏试验（AST）可实现快速且精确的治疗。本研究的目的是通过结合流式细胞术进行病原体筛查、基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）进行微生物鉴定以及使用VITEK 2系统直接分析尿液样本，来缩短尿路感染的诊断时间。首先，我们使用UF5000通过流式细胞术选择阳性尿液样本，将阳性阈值设定为每毫升150个细菌。在使用MALDI-TOF MS确认鉴定结果并对尿液样本进行过滤后，我们使用VITEK 2直接测试AST N388卡。我们总共测试了来自尿液样本的211份样本。头孢西丁、厄他培南、亚胺培南、庆大霉素、萘啶酸、环丙沙星、磷霉素和呋喃妥因没有主要重要错误（MIE），而氨苄西林、头孢呋辛和妥布霉素显示出较高的MIE。头孢吡肟、亚胺培南和妥布霉素没有主要错误（ME）。磷霉素是ME最多的抗生素。mE最多的抗生素是头孢他啶。总分类一致性（CA）为97.4%，95%置信区间为（96.8 - 97.9）。这里提出的直接从尿液样本进行的AST缩短了一天时间，在标准诊断的敏感性方面没有显著损失。因此，我们假设这种方法更符合实际情况，更适合人体抗生素浓度。
