由克隆 ST131-O25b 占主导地位的同种菌株引起的产超广谱β-内酰胺酶大肠埃希菌导致的尿路感染复发。

Recurrence of urinary tract infections with extended-spectrum β-lactamase-producing Escherichia coli caused by homologous strains among which clone ST131-O25b is dominant.

机构信息

Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy and Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden; Department of Clinical Microbiology, Sahlgrenska University Hospital, Gothenburg, Sweden.

出版信息

J Glob Antimicrob Resist. 2020 Sep;22:126-132. doi: 10.1016/j.jgar.2020.01.024. Epub 2020 Feb 12.

DOI:10.1016/j.jgar.2020.01.024

PMID:32061816

Abstract

OBJECTIVES

Bacterial features associated with recurrent urinary tract infections (RUTIs) due to extended-spectrum β-lactamase-producingEscherichia coli (ESBL-E. coli) are not well understood. In this study, phylogenetic groups and ST131 subclones were investigated to assess strain homology of ESBL-E. coli isolates in patients with RUTIs in inpatient and outpatient settings in western Sweden.

METHODS

Almost all isolates (319/356) from 123 patients with 2-7 episodes (median 2 episodes) of ESBL-E. coli UTI within 1 year were examined for seven E. coli phylogroups, the ST131-O25b clone and its subclone fimH30-Rx. Antimicrobial resistance and ESBL genes were determined for the index isolates. A subset of isolates was typed using pulsed-field gel electrophoresis (PFGE).

RESULTS

The same phylogroup and ST131 subclones were seen for all recurrences in 119/123 patients, and PFGE confirmed strain homology in recurrences for 43/44 patients tested. Phylogroup B2 dominated (56%), followed by D (19%) and F (10%). ST131-O25b andfimH30-Rx isolates were detected in 44% and 30%, respectively. CTX-M group 1 (71%) predominated. Elderly patients were in the majority. There were no associations between patient demographics or time to recurrence and bacterial characteristics. The fimH30-Rx subclone was associated with a higher number of recurrences (P = 0.015) compared with the remaining B2 isolates.

CONCLUSION

In ESBL-E. coli RUTI, most recurrences were caused by the initial infecting strain. The high frequency of the multidrug-resistant fimH30-Rx subclone and its association with multiple recurrences warrants further attention and early detection of this subclone in patients at risk of developing RUTI with ESBL-E. coli.

摘要

目的

由产超广谱β-内酰胺酶的大肠杆菌（ESBL-E. coli）引起的复发性尿路感染（RUTI）的细菌特征尚不清楚。本研究调查了进化枝群和 ST131 亚克隆，以评估在瑞典西部住院和门诊环境中患有 RUTI 的患者中 ESBL-E. coli 分离株的菌株同源性。

方法

对 123 名患者的 319/356 株（中位数为 2 次发作）的 ESBL-E. coli UTI 进行了 2-7 次发作（中位数为 2 次），检查了 7 株大肠杆菌进化枝群、ST131-O25b 克隆及其 fimH30-Rx 亚克隆。对指数分离株进行了抗生素耐药性和 ESBL 基因的测定。使用脉冲场凝胶电泳（PFGE）对分离株进行了亚型分析。

结果

在 119/123 名患者的所有复发中都观察到相同的进化枝群和 ST131 亚克隆，44 名经测试的患者中有 43 名的 PFGE 证实了复发的菌株同源性。进化枝群 B2 占主导地位（56%），其次是 D（19%）和 F（10%）。检测到 ST131-O25b 和 fimH30-Rx 分离株分别为 44%和 30%。CTX-M 组 1（71%）占主导地位。老年患者居多。患者的人口统计学特征或复发时间与细菌特征之间无关联。与其余 B2 分离株相比，fimH30-Rx 亚克隆与更多的复发次数相关（P=0.015）。