Scholarlink

Background <p>Hospital wastewater (HWW) is a significant reservoir for multidrug-resistant (MDR) bacteria and antimicrobial resistance (AMR) genes, posing serious public health risks. This study investigated the phenotypic and genotypic resistance profiles of <i>Escherichia coli</i> (<i>E. coli</i>) isolates from HWW in Shiraz, Iran. Thirty-six HWW samples (18 influent, 18 effluent) were collected weekly over six weeks from three major hospitals. <i>E. coli</i> isolates were identified and assessed for antimicrobial susceptibility, extended-spectrum β-lactamase (ESBL) and carbapenemase production, resistance genes, phylogroups, and sequence types (STs).</p> Results <p>A total of 68 <i>E. coli</i> isolates were obtained (33 influent, 35 effluent). High resistance rates were observed for ampicillin (97.1%), cefazolin, and amoxicillin/clavulanic acid (86.8%). The lowest resistance rates were to imipenem (5.9%), meropenem (13.2%), and chloramphenicol (19.1%). MDR and extensively drug-resistant (XDR) profiles were identified in 80.9% and 22.1% of isolates, respectively. ESBL production was found in 57.4% of isolates. All nine carbapenem-resistant isolates were tested by both modified carbapenem inactivation method (mCIM) and EDTA-CIM (eCIM); eight (88.9%) were positive by mCIM, while all were negative by eCIM. Resistance genes detected included <i>bla</i>TEM (39.7%), <i>bla</i>CTX-M (33.8%), and <i>bla</i>SHV (2.9%). Three isolates carried <i>bla</i>OXA-48, while one carried <i>bla</i>IMP and another carried <i>bla</i>VIM. Phylogroup B2 was most frequent (22.1%), with ST131 being the dominant type (33.8%).</p> Conclusion <p>In conclusion, HWW may serve as a potential reservoir for resistant and pathogenic <i>E. coli</i> isolates, indicating the importance of monitoring wastewater as a step in addressing the issue of AMR.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

High prevalence of MDR and XDR Escherichia coli in hospital wastewater from Shiraz, Iran: ESBL and carbapenemase production

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年10月9日

查看全文
  • Abolfazl Rafati Zomorodi,
  • Mohammad Reza Samaei,
  • Himen Salimizand,
  • Mohammad Hassan Parvizi Mashhadi,
  • Mohammad Motamedifar

摘要

Background

Hospital wastewater (HWW) is a significant reservoir for multidrug-resistant (MDR) bacteria and antimicrobial resistance (AMR) genes, posing serious public health risks. This study investigated the phenotypic and genotypic resistance profiles of Escherichia coli (E. coli) isolates from HWW in Shiraz, Iran. Thirty-six HWW samples (18 influent, 18 effluent) were collected weekly over six weeks from three major hospitals. E. coli isolates were identified and assessed for antimicrobial susceptibility, extended-spectrum β-lactamase (ESBL) and carbapenemase production, resistance genes, phylogroups, and sequence types (STs).

Results

A total of 68 E. coli isolates were obtained (33 influent, 35 effluent). High resistance rates were observed for ampicillin (97.1%), cefazolin, and amoxicillin/clavulanic acid (86.8%). The lowest resistance rates were to imipenem (5.9%), meropenem (13.2%), and chloramphenicol (19.1%). MDR and extensively drug-resistant (XDR) profiles were identified in 80.9% and 22.1% of isolates, respectively. ESBL production was found in 57.4% of isolates. All nine carbapenem-resistant isolates were tested by both modified carbapenem inactivation method (mCIM) and EDTA-CIM (eCIM); eight (88.9%) were positive by mCIM, while all were negative by eCIM. Resistance genes detected included blaTEM (39.7%), blaCTX-M (33.8%), and blaSHV (2.9%). Three isolates carried blaOXA-48, while one carried blaIMP and another carried blaVIM. Phylogroup B2 was most frequent (22.1%), with ST131 being the dominant type (33.8%).

Conclusion

In conclusion, HWW may serve as a potential reservoir for resistant and pathogenic E. coli isolates, indicating the importance of monitoring wastewater as a step in addressing the issue of AMR.