Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Eötvös Utca 6., Szeged, 6720, Hungary.
Institute of Clinical Microbiology, Faculty of Medicine, University of Szeged, Semmelweis utca 6., Szeged, 6725, Hungary.
Biol Futur. 2020 Jun;71(1-2):175-182. doi: 10.1007/s42977-020-00016-6. Epub 2020 Jun 4.
Urinary tract infections (UTIs) are some of the most common infections affecting humans worldwide. Occurrence of atypical, lactose non-fermenting, biochemically "inactive" strains of E. coli in clinical material has been described in the literature, which may cause a significant diagnostic challenge. The present retrospective microbiological study was carried out using isolates and data collected between January 1, 2013, and December 31, 2017, at the Institute of Clinical Microbiology. n = 24,285 positive urine samples were noted during the study period, out of which, samples positive for either lac + and lac- E. coli were included in the analysis. E. coli represented n = 7075 (55.8% ± 4.6%) of outpatient and n = 4916 (42.4% ± 3.6%) of inpatient isolates. n = 401 (3.3%; 80.2 ± 14.6/year) lac- E. coli isolates were identified from urinary tract infections. The ratio of lac- E. coli isolates was significantly higher in outpatient samples (262 vs. 139). Resistance levels of lac- isolates for antibiotics commonly used for treating UTIs were significantly higher for both inpatient and outpatient isolates: norfloxacin, ciprofloxacin, fosfomycin and nitrofurantoin. It is essential to pay attention to the presence of lac- strains, and their omission from clinical material during diagnostic procedures may have significant consequences for epidemiological studies and therapy.
尿路感染（UTI）是全球范围内最常见的感染之一。文献中已经描述了在临床标本中出现非典型、乳糖非发酵、生化“无活性”的大肠杆菌菌株，这可能会给诊断带来重大挑战。本回顾性微生物学研究使用了 2013 年 1 月 1 日至 2017 年 12 月 31 日期间在临床微生物学研究所收集的分离株和数据进行。在研究期间，共注意到 24285 份阳性尿液样本，其中，对既产乳糖又不产乳糖的大肠杆菌样本进行了分析。大肠杆菌代表 n=7075（55.8%±4.6%）门诊和 n=4916（42.4%±3.6%）住院分离株。从尿路感染中鉴定出 401（3.3%；80.2±14.6/年）株不产乳糖的大肠杆菌分离株。门诊样本中不产乳糖的大肠杆菌分离株比例明显更高（262 比 139）。门诊和住院分离株对治疗 UTI 常用抗生素的耐药水平明显更高：诺氟沙星、环丙沙星、磷霉素和呋喃妥因。注意产乳糖菌株的存在很重要，在诊断过程中忽略其在临床标本中的存在可能会对流行病学研究和治疗产生重大影响。
