Distinct Characteristics of Escherichia coli Isolated from Patients with Urinary Tract Infections in a Medical Center at a Ten-Year Interval.

Wei-Hung Lin,Yi-Hsien Hsieh,Pei-Yun Kuo,Yen-Zhen Zhang,Tran Thi Thuy Duong,Li-Li Wen,Shining Wang,Ming-Cheng Wang,Cheng-Yen Kao,Tran Thi Dieu Thuy,Po-Yao Liu,Po-Shun Chen

doi:10.3390/pathogens10091156

Abstract

Escherichia coli causing urinary tract infections (UTIs) are one of the most common outpatient bacterial infections. This study aimed to compare the characteristics of E. coli isolated from UTI patients in a single medical center in 2009–2010 (n = 504) and 2020 (n = 340). The antimicrobial susceptibility of E. coli was determined by the disk diffusion method. PCRs were conducted to detect phylogenetic groups, ST131, K1 capsule antigen, and 15 virulence factors. Phylogenetic group B2 dominated in our 2009–2010 and 2020 isolates. Moreover, no phylogenetic group E strains were isolated in 2020. E. coli isolates in 2020 were more susceptible to amoxicillin, ampicillin/sulbactam, cefuroxime, cefmetazole, ceftazidime, cefoxitin, tetracycline, and sulfamethoxazole/trimethoprim, compared to the isolates in 2009–2010. Extensively drug-resistant (XDR)-E. coli in 2009–2010 were detected in groups B1 (5 isolates), B2 (12 isolates), F (8 isolates), and unknown (1 isolate). In 2020, XDR-E. coli were only detected in groups A (2 isolates), B2 (5 isolates), D (1 isolate), and F (4 isolates). The prevalence of virulence factor genes aer and fimH were higher in E. coli in 2009–2010 compared to those in 2020. In contrast, afa and sat showed higher frequencies in E. coli isolates in 2020 compared to E. coli in 2009–2010.

Highlights

Urinary tract infection (UTI) is one of the most common outpatient bacterial infections worldwide with a lifetime incidence of 50–60% in adult women and contribute to a substantial financial burden on society [1]
We previously divided UTI patients into six age groups (≤3, 4–20, 21–40, 41–60, 61–80, and >80 years old) and reported that E. coli isolated from the elderly with UTI were more resistant to antimicrobial agents and had fewer virulence factors compared to E. coli isolated from the younger age groups [5]
When the strains isolated from patient age groups ≤3 and >80 were compared, we found strains isolated from the elderly age group had fewer virulence factors, including papGII (p = 0.001), papGIII (p = 0.028), cnf1 (p = 0.015), usp (p = 0.009), and hlyA (p = 0.001), compared to the E. coli isolated from patient age group ≤3, in 2009–2010 (Table 6)

Summary

Introduction

Urinary tract infection (UTI) is one of the most common outpatient bacterial infections worldwide with a lifetime incidence of 50–60% in adult women and contribute to a substantial financial burden on society [1]. Fimbriae [12], iron acquisition systems [13], iron-regulated gene homologue adhesin Iha [14], ferric aerobactin receptor IutA [15], cytotoxic necrotizing factor 1 (Cnf1) [16], hemolysin (HlyA) [16], uropathogenic specific protein (Usp) [17], and outer membrane protease T (OmpT) [18], are shown as important virulence factors of E. coli in murine uropathogenesis Carriage of these urovirulence factors is thought to enhance UPEC pathogenicity and is used to measure and categorize clinical UPEC strains isolated from different patient populations [19,20,21]. E. coli isolated from the elderly have fewer virulence factors compared to those isolated from younger age groups [5]

Objectives

Methods

Results

Conclusion