{"title":"Colistin resistance in ESBL- and Carbapenemase-producing Escherichia coli and Klebsiella pneumoniae clinical isolates in Cambodia","authors":"","doi":"10.1016/j.jgar.2024.06.017","DOIUrl":null,"url":null,"abstract":"<div><h3>Objectives</h3><p>Despite the critical importance of colistin as a last-resort antibiotic, limited studies have investigated colistin resistance in human infections in Cambodia. This study aimed to investigate the colistin resistance and its molecular determinants among Extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing (CP) <em>Klebsiella pneumoniae</em> (<em>K. pneumoniae</em>) and <em>Escherichia coli</em> (<em>E. coli</em>) isolated in Cambodia between 2016 and 2020.</p></div><div><h3>Methods</h3><p><em>E. coli</em> (<em>n</em> = 223) and <em>K. pneumoniae</em> (<em>n</em> = 39) were tested for colistin minimum inhibitory concentration (MIC) by broth microdilution. Resistant isolates were subjected to polymerase chain reaction (PCR) for detection of mobile colistin resistance genes (<em>mcr</em>) and chromosomal mutations in the two-component system (TCS).</p></div><div><h3>Results</h3><p>Eighteen isolates (10 <em>K. pneumoniae</em> and 8 <em>E. coli</em>) revealed colistin resistance with a rate of 5.9% in <em>E. coli</em> and 34.8% in <em>K. pneumoniae</em> among ESBL isolates, and 1% in <em>E. coli</em> and 12.5% in <em>K. pneumoniae</em> among CP isolates. The resistance was associated with <em>mcr</em> variants (13/18 isolates, <em>mcr-1, mcr</em>-<em>3</em>, and <em>mcr-8.2</em>) and TCS mutations within <em>E. coli</em> and <em>K. pneumoniae</em>, with the first detection of <em>mcr-8.2</em> in Cambodia, the discovery of new mutations potentially associated to colistin resistance in the TCS of <em>E. coli</em> (PhoP I47V, PhoQ N352K, PmrB G19R, and PmrD G85R) and the co-occurrence of <em>mcr</em> genes and colistin resistance conferring TCS mutations in 11 of 18 isolates.</p></div><div><h3>Conclusions</h3><p>The findings highlight the presence of colistin resistance in ESBL- and CP- <em>Enterobacteriaceae</em> involved in human infections in Cambodia as well as chromosomal mutations in TCS and the emergence of <em>mcr</em>-<em>8.2</em> in <em>E. coli</em> and <em>K. pneumoniae</em>. It underscores the need for continuous surveillance, antimicrobial stewardship, and control measures to mitigate the spread of colistin resistance.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001346/pdfft?md5=baecadd2c501f3b5b9504df2e7990299&pid=1-s2.0-S2213716524001346-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of global antimicrobial resistance","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2213716524001346","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
Objectives
Despite the critical importance of colistin as a last-resort antibiotic, limited studies have investigated colistin resistance in human infections in Cambodia. This study aimed to investigate the colistin resistance and its molecular determinants among Extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing (CP) Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) isolated in Cambodia between 2016 and 2020.
Methods
E. coli (n = 223) and K. pneumoniae (n = 39) were tested for colistin minimum inhibitory concentration (MIC) by broth microdilution. Resistant isolates were subjected to polymerase chain reaction (PCR) for detection of mobile colistin resistance genes (mcr) and chromosomal mutations in the two-component system (TCS).
Results
Eighteen isolates (10 K. pneumoniae and 8 E. coli) revealed colistin resistance with a rate of 5.9% in E. coli and 34.8% in K. pneumoniae among ESBL isolates, and 1% in E. coli and 12.5% in K. pneumoniae among CP isolates. The resistance was associated with mcr variants (13/18 isolates, mcr-1, mcr-3, and mcr-8.2) and TCS mutations within E. coli and K. pneumoniae, with the first detection of mcr-8.2 in Cambodia, the discovery of new mutations potentially associated to colistin resistance in the TCS of E. coli (PhoP I47V, PhoQ N352K, PmrB G19R, and PmrD G85R) and the co-occurrence of mcr genes and colistin resistance conferring TCS mutations in 11 of 18 isolates.
Conclusions
The findings highlight the presence of colistin resistance in ESBL- and CP- Enterobacteriaceae involved in human infections in Cambodia as well as chromosomal mutations in TCS and the emergence of mcr-8.2 in E. coli and K. pneumoniae. It underscores the need for continuous surveillance, antimicrobial stewardship, and control measures to mitigate the spread of colistin resistance.
期刊介绍:
The Journal of Global Antimicrobial Resistance (JGAR) is a quarterly online journal run by an international Editorial Board that focuses on the global spread of antibiotic-resistant microbes.
JGAR is a dedicated journal for all professionals working in research, health care, the environment and animal infection control, aiming to track the resistance threat worldwide and provides a single voice devoted to antimicrobial resistance (AMR).
Featuring peer-reviewed and up to date research articles, reviews, short notes and hot topics JGAR covers the key topics related to antibacterial, antiviral, antifungal and antiparasitic resistance.