Journal of global antimicrobial resistance最新文献

{"title":"Chloroquine resistance transporter drives divergent multilocus drug resistance genetic backgrounds and susceptibility in Gambian Plasmodium falciparum.","authors":"Ndey Fatou Drammeh, Fatoumata Bojang, Nora Nghochuzie Nganyewo, Aminata Seedy Jawara, Baboucarr Manneh, Simon Correa, Brandon Nji Amambua-Ngwa, Haddijatou Mbye, Eniyou Cheryll Oriero, Colin J Sutherland, Umberto D'Alessandro, Alfred Amambua-Ngwa","doi":"10.1016/j.jgar.2026.04.003","DOIUrl":"https://doi.org/10.1016/j.jgar.2026.04.003","url":null,"abstract":"<p><strong>Background: </strong>Sustained antimalarial drug use against Plasmodium falciparum has often resulted in drug resistance and selection of associated genetic markers in malaria endemic populations. The genetic markers of resistance to legacy drugs like chloroquine persist in The Gambia. This study assesses the effect of these legacy drug resistance genomic backgrounds on in vitro responses to antimalarial drugs in The Gambia.</p><p><strong>Methods: </strong>Plasmodium falciparum drug resistance genotypes at pfcrt, pfmdr1, pfdhfr, pfdhps, and pfkelch13 genes was determine from amplicon sequencing of 364 isolates. In vitro 50% growth inhibitory concentrations (IC₅₀s) were determined for 68 isolates to chloroquine, dihydroartemisinin, lumefantrine, mefloquine, piperaquine, and amodiaquine. In vitro response to drugs were assessed for parasite groups with different major multilocus drug resistance genetic backgrounds.</p><p><strong>Results: </strong>Two main multilocus drug resistance backgrounds driven by pfcrt haplotypes (CVMNK/CVIET) were observed. CVIET (62%) isolates were resistant to chloroquine, whereas CVMNK were less sensitive to mefloquine and dihydroartemisinin. The pfmdr1 NFD haplotype was 60% prevalent, with 184F at 67%. Infections with CVIET-NFD combination (31.7%) had the highest chloroquine IC₅₀s. Pfdhfr S108N (98%) and pfdhps A437G (85%) mutants were highly prevalent. No validated pfkelch13 resistance mutations were detected.</p><p><strong>Conclusion: </strong>ACTs remain effective in The Gambia, supported by the absence of pfkelch13 mutations. However, reversion to chloroquine sensitivity tend to result in reduced sensitivity to ACT drugs. These genotype-phenotype dynamics needs continuous monitoring to guide drug interventions towards malaria elimination.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147690440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic insights into a multidrug-resistant Pseudomonas aeruginosa ST463 clinical isolate co-harbouring bla_KPC-2 and bla_NDM-9.","authors":"Yi Huang, Qiao Li, Fang He, Juan Xu, Andrey Bakunovich, Chao Song","doi":"10.1016/j.jgar.2026.04.008","DOIUrl":"10.1016/j.jgar.2026.04.008","url":null,"abstract":"<p><strong>Objective: </strong>Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a critical pathogen in healthcare-associated infections. In this study, we characterize a clinical P. aeruginosa isolate from China that simultaneously harbours bla_KPC-2 and bla_NDM-9, two clinically important carbapenemase genes.</p><p><strong>Methods: </strong>Strain MZ67-2 was identified using the VITEK MS system, and antimicrobial susceptibility testing was performed by broth microdilution. Whole-genome sequencing was conducted on the Illumina NovaSeq 6000 platform and assembled using Unicycler (v0.4.7). MLST and antimicrobial resistance gene identification were performed using BacWGSTdb. Phylogenetic relationships between MZ67-2 and other P. aeruginosa strains co-harbouring bla_KPC and bla_NDM were inferred by SNP-based analysis and visualized using iTOL.</p><p><strong>Results: </strong>P. aeruginosa MZ67-2 was assigned to sequence type (ST) 463 and serotype O4. The isolate exhibited a multidrug-resistant phenotype, showing resistance to all tested antimicrobial agents except colistin. Whole-genome analysis identified a total of 17 antimicrobial resistance genes, including the carbapenemase-encoding genes bla_KPC-2 and bla_NDM-9. Analysis of the NCBI GenBank database indicates that P. aeruginosa strains carrying bla_KPC or bla_NDM alone are globally prevalent and may serve as reservoirs for the emergence of co-harbouring strains. In contrast, isolates carrying both genes remain rare, with only seven cases reported worldwide to date (2020-2025), suggesting an evolutionary shift toward multi-carbapenemase carriage under the selective pressure of novel β-lactam/β-lactamase inhibitor use.</p><p><strong>Conclusion: </strong>In summary, we report a clinical P. aeruginosa isolate from China co-harbouring bla_KPC-2 and bla_NDM-9. The emergence of multi-carbapenemase-producing strains poses a serious threat to antimicrobial therapy, underscoring the need for continuous clinical surveillance.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":"30-32"},"PeriodicalIF":3.2,"publicationDate":"2026-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147674113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ceftazidime-avibactam-based regimens for the treatment of central nervous system infections caused by carbapenem-resistant Klebsiella pneumoniae in a pediatric patient.","authors":"Liming He, Wanzhen Li, Weiming Chen, Yixue Wang, Xiaofen Liu, Pan Fu, Chuanqing Wang, Junqi Zhang, Guoping Lu, Gangfeng Yan, Jing Zhang","doi":"10.1016/j.jgar.2026.04.002","DOIUrl":"https://doi.org/10.1016/j.jgar.2026.04.002","url":null,"abstract":"<p><strong>Objective: </strong>Carbapenem-resistant Klebsiella pneumoniae (CRKP) central nervous system (CNS) infections are difficult to treat in children because effective and safe therapeutic options are limited. We report a pediatric case of CRKP meningitis successfully treated with ceftazidime-avibactam (CZA) combination with intraventricular polymyxin B (PMB).</p><p><strong>Methods: </strong>A 9-year-old child with severe traumatic brain injury and multiple prior neurosurgical procedures developed CRKP meningitis. After pathogen identification, antimicrobial therapy was switched to CZA plus intraventricular PMB, and the ventriculoperitoneal shunt was externalized. Clinical outcomes, cerebrospinal fluid (CSF) parameters, microbiological clearance, and plasma and CSF concentration of CZA were monitored during treatment.</p><p><strong>Results: </strong>After CRKP was identified, therapy was adjusted to CZA (62.5 mg/kg every 8 h, administered as a 2-h infusion) plus intraventricular PMB based on susceptibility results. Fever resolved within 3 days of CZA initiation. CSF cultures became negative, and CSF parameters gradually normalized. Neurological status improved, and the patient was transferred to a rehabilitation facility. Pharmacokinetic analysis showed blood-brain barrier penetration rates of 19.4% for ceftazidime and 29.9% for avibactam.</p><p><strong>Conclusions: </strong>This report adds to the limited pharmacokinetic/pharmacodynamic (PK/PD) evidence for ceftazidime-avibactam in pediatric CNS infections. It also supports the potential role of ceftazidime-avibactam combined with intraventricular polymyxin B as a therapeutic option for CRKP meningitis in children. Further studies are needed to optimize dosing strategies and evaluate long-term safety in the pediatric population.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147674100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro evaluation of the novel antibiotic zosurabalpin against carbapenem-resistant Acinetobacter baumannii clinical isolates.","authors":"Fabiana Diaco, Luisa Torrini, Lucilla Caivano, Matteo Rossi, Federica Dominelli, Gianluca Puggioni, Federica Sacco, Agnese Viscido, Severine Louvel, Guido Antonelli","doi":"10.1016/j.jgar.2026.04.001","DOIUrl":"https://doi.org/10.1016/j.jgar.2026.04.001","url":null,"abstract":"<p><strong>Objective: </strong>Evaluate the in vitro activity of zosurabalpin (ZAB), a novel tethered macrocyclic peptide antibiotic, developed by Roche (Switzerland), against carbapenem-resistant Acinetobacter baumannii (CRAB) isolates.</p><p><strong>Methods: </strong>A total of 100 clinical CRAB isolates were obtained from respiratory samples and blood cultures of hospitalized patients at University Hospital Policlinico Umberto I in Rome. Carbapenem resistance was confirmed by meropenem susceptibility testing with the MicroScan WalkAway system (Beckman Coulter, USA). These isolates were tested for their susceptibility to ZAB and cefiderocol (FDC). ZAB MICs were determined by broth microdilution according to CLSI guidelines, using homemade cation-adjusted Mueller-Hinton broth (CAMHB) supplemented with 20% heat-inactivated horse serum. Instead, antimicrobial susceptibility to FDC was tested using the microdilution method with homemade iron depleted (ID)-CAMHB. The concentrations of both antibiotics ranged from 32 mg/L to ≤ 0.015 mg/L. Clinical breakpoints for FDC and meropenem were defined according to the EUCAST 2025 guidelines.</p><p><strong>Results: </strong>ZAB demonstrated potent in vitro activity against all clinical CRAB isolates, with an MIC₉₀ value of 0.25 mg/L and MIC values ranging from ≤0.015 to 0.5 mg/L. Eleven of the 100 clinical isolates showed resistance to FDC, with MIC values between 4 and >32 mg/L. Interestingly, these strains were susceptible to ZAB, with MIC values between 0.06 and 0.5 mg/L.</p><p><strong>Conclusions: </strong>These findings indicate that ZAB exhibits strong in vitro activity against CRAB including strains resistant to last-line commercially available antibiotics such as FDC.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147654360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in antimicrobial resistance among Enterobacter isolates in an Australian local health district.","authors":"Victoria Maseko, Colin H Cortie, Kylie J Mansfield, Sandra Jones, Martina Sanderson-Smith, Danielle Thompson, Spiros Miyakis, Caitlin Keighley, Chloe Story","doi":"10.1016/j.jgar.2026.03.016","DOIUrl":"10.1016/j.jgar.2026.03.016","url":null,"abstract":"<p><strong>Background: </strong>Antimicrobial resistance (AMR) is a universal health issue, causing significant morbidity and mortality. Enterobacter species is a gram-negative bacterial pathogen that has intrinsic and acquired resistance to multiple antibiotic classes.</p><p><strong>Aim: </strong>To determine trends in antibiotic resistance among Enterobacter isolates in community and hospital settings within the Illawarra Shoalhaven region of NSW, Australia.</p><p><strong>Methods: </strong>We analysed Enterobacter spp. isolates from a hospital-based (N = 2131) and a community-based (N = 1123) laboratory in Illawarra Shoalhaven, between 2007 and 2018. Trimethoprim, gentamicin, tobramycin, amikacin, ciprofloxacin, and meropenem resistance over the 11-y period was determined, and resistance trends and rates between community and hospital settings were compared, using statistical analysis (Pearson's chi-squared tests).</p><p><strong>Findings: </strong>AMR was significantly higher in hospital (14.9%) compared to community (8.9%) isolates. AMR reduced over the 11-y period for all antibiotics except amikacin and meropenem, for which resistance remained low throughout.</p><p><strong>Conclusions: </strong>Antibiotic resistance in Enterobacter spp. was higher in the hospital setting; however, resistance over time either significantly reduced (for most antibiotics) or remained stable (for some antibiotics) in both groups. The reduction was more pronounced in the hospital setting. This highlights the contribution of hospital-based infection-control measures, including the antimicrobial stewardship program.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":"33-36"},"PeriodicalIF":3.2,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147638922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complete genome sequences and structural variants of pESI-like plasmids in multidrug-resistant Salmonella Infantis carrying blaCTX-M-65 from retail chicken meat in South Korea","authors":"Tae-Min La ,&nbsp;Taesoo Kim ,&nbsp;Sang-Won Lee ,&nbsp;Ji-Yeon Hyeon","doi":"10.1016/j.jgar.2026.01.005","DOIUrl":"10.1016/j.jgar.2026.01.005","url":null,"abstract":"<div><h3>Objective</h3><div>This study reports complete chromosome and pESI-like megaplasmid sequences of multidrug-resistant <em>Salmonella enterica</em> serovar Infantis (<em>S.</em> Infantis) isolates obtained from retail chicken meat in South Korea in 2023 and characterizes their antimicrobial resistance (AMR) gene repertoire and the structural diversity of their pESI-like plasmids.</div></div><div><h3>Methods</h3><div>Twenty-one multidrug-resistant <em>S</em>. Infantis isolates were subjected to whole-genome sequencing using Illumina NextSeq and Oxford Nanopore MinION platforms. Hybrid assemblies were generated using Trycycler v0.5.0 and corrected using Polypolish v1.2.3. AMR genes were identified, and plasmid structures were reconstructed and visualized using Proksee.</div></div><div><h3>Results</h3><div>All isolates belonged to sequence type ST32 and carried pESI-like megaplasmid encoding multiple AMR genes. Conserved resistance genes included <em>aac(3)-IVa, aph(4)-Ia, bla</em>_CTX-M-65, and <em>tet</em>(A), while <em>ant(3″)-Ia, aph(3′)-Ia, dfrA14, floR,</em> and <em>sul1</em> were variably present. Comparative plasmid analysis revealed six plasmid structural variants (Types A–F), primarily distinguished by deletions within AMR regions. Type A retained all resistance loci, whereas Types B–F exhibited partial loss of regions harbouring <em>aph(3′)-Ia, dfrA14, floR</em>, or <em>sul1</em>. Comparative plasmid mapping showed that the Korean pESI-like plasmids exhibited high overall structural similarity to internationally reported pESI-like plasmids, including those from the UK and USA.</div></div><div><h3>Conclusions</h3><div>These complete genome sequences expand the current knowledge of pESI-like plasmid diversity in <em>S</em>. Infantis and highlight their role in the dissemination of multidrug resistance in the poultry sector. Continued genomic surveillance is warranted to monitor the emergence and spread of high-risk <em>S</em>. Infantis clones across the food chain.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"47 ","pages":"Pages 38-40"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146040813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of ESBL and carbapenemase producers and polymyxin- and fosfomycin-resistant Enterobacterales among pets in a veterinary clinic, Egypt","authors":"Atef Oreiby ,&nbsp;Samanta Freire ,&nbsp;Alaaeldin Mohamed Saad ,&nbsp;Mohamed A. Donia ,&nbsp;Hazim O. Khalifa ,&nbsp;Patrice Nordmann ,&nbsp;Laurent Poirel ,&nbsp;Mustafa Sadek","doi":"10.1016/j.jgar.2026.01.006","DOIUrl":"10.1016/j.jgar.2026.01.006","url":null,"abstract":"<div><h3>Objectives</h3><div>This study investigates the transmission risk of ESBL producers, carbapenemase producers, polymyxin-resistant, and fosfomycin-resistant Enterobacterales from healthy and sick dogs and cats in Tanta governorate, Nile Delta region, Egypt.</div></div><div><h3>Methods</h3><div>A total of 206 different samples were collected from healthy and sick pets. Samples were screened for different resistance mechanisms using mSuperCarba, SuperPolymyxin, ChromID ESBL, and SuperFOS selective plates. Antimicrobial susceptibility testing was performed using disk diffusion and broth microdilution techniques. Phenotypic confirmation of resistance traits was done using various rapid diagnostic tests. PCR screening was performed for ESBLs, carbapenemases, <em>mcr</em>, and <em>fosA</em> genes. Molecular typing and clonality evaluation were also performed.</div></div><div><h3>Results</h3><div>Isolates (<em>Escherichia coli</em>, n = 17 and <em>Enterobacter cloacae</em>, n = 1) showing acquired multidrug resistance phenotype were identified in 13 animals, accounting for 25% of the total cases. Production of ESBLs was the most prevalent resistance mechanism, with the corresponding producers predominantly carrying the <em>bla</em>_CTX-M-15 gene (92.3%), whereas the <em>bla</em>_SHV-12 gene was identified in a single isolate. The <em>bla</em>_NDM-5 carbapenemase gene was identified in three <em>E. coli</em> isolates, those latter sharing the same sequence type (ST361). A single colistin-resistant <em>E. coli</em> was isolated and carried both <em>mcr-1</em> and <em>bla</em>_CTX-M-15, whereas a fosfomycin-resistant <em>E. coli</em> isolate coproduced <em>fosA5</em> and SHV-12. Notably, 69.2% of resistant bacteria were isolated from sick pets compared with 30.7% in healthy ones. <em>E. coli</em> isolates showed various sequence types, with ESBL-producing strains belonging to seven different STs and NDM-5 enzyme producers belonging to ST361.</div></div><div><h3>Conclusions</h3><div>This study highlights significant antimicrobial resistance in companion animals and the potential risk for zoonotic transmission.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"47 ","pages":"Pages 49-54"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146018513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic analysis of a penicillin-susceptible, methicillin-resistant Staphylococcus aureus (ST9332) harboring triple mecA substitutions","authors":"Qin Tang ,&nbsp;Yuting Sun ,&nbsp;Fei Yan ,&nbsp;Lu Lin ,&nbsp;Huarong Yu ,&nbsp;Jinxing Chen","doi":"10.1016/j.jgar.2026.01.004","DOIUrl":"10.1016/j.jgar.2026.01.004","url":null,"abstract":"<div><h3>Research Background</h3><div><em>mecA</em>-positive MRSA is generally assumed to be broadly non-susceptible to β-lactams. Reports of penicillin-susceptible MRSA (PS-MRSA) challenge this view. We describe CDSYY2023, a cefoxitin-resistant yet penicillin-susceptible MRSA carrying three <em>mecA</em> substitutions (S225R, K239E, E246G) and a novel sequence type, ST9332.</div></div><div><h3>Methods</h3><div>The strain was recovered from the sputum of a hospitalised older adult with dementia and identified as <em>S. aureus</em> by MALDI-TOF MS (Autobio MS1000). Susceptibility testing followed CLSI procedures on VITEK 2 with parallel Mueller–Hinton edge tests (cefoxitin, penicillin). Key readouts were verified by Etest and independently confirmed at a referral laboratory. Whole-genome sequencing (Illumina HiSeq 2500) was assembled de novo with SOAPdenovo2. Functional annotation used COG/GO/KEGG; resistance and virulence genes were queried against CARD and VFDB. MLST was assigned and registered via PUBMLST.</div></div><div><h3>Results</h3><div>The draft genome is ∼2 750 950 bp (GC 32.94%), with no plasmids, encoding 2521 CDSs, 55 tRNAs and 19 rRNAs. MLST designated ST9332. Phenotypically, VITEK 2 and MH edge tests agreed on cefoxitin resistance (17 mm), while penicillin remained susceptible (25 mm; Etest MIC 0.032 µg/mL), contrary to expectations for a <em>mecA</em>-positive background. Genomics revealed the triple <em>mecA</em> substitutions noted above and no definitive evidence of <em>blaZ</em>. The resistome/virulome included multiple efflux and regulatory elements.</div></div><div><h3>Conclusions</h3><div>CDSYY2023 is a PS-MRSA with triple-substituted <em>mecA</em> on a novel MLST background (ST9332). Its penicillin-susceptible/cefoxitin-resistant profile likely reflects a specific <em>mecA</em> sequence/regulatory context, highlighting the limits of relying solely on cefoxitin-based screening to infer β-lactam behaviour.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"47 ","pages":"Pages 20-26"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146029678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial susceptibility analysis of diarrhoeagenic Escherichia coli isolated from outpatients in Beijing, from 2021 to 2024","authors":"Bing Lv,&nbsp;Xin Zhang,&nbsp;Hui Xu,&nbsp;Changying Lin,&nbsp;Ying Huang,&nbsp;Mei Qu,&nbsp;Daitao Zhang,&nbsp;Quanyi Wang","doi":"10.1016/j.jgar.2026.01.007","DOIUrl":"10.1016/j.jgar.2026.01.007","url":null,"abstract":"<div><h3>Objectives</h3><div>This study aimed to investigate the prevalence of diarrhoeagenic <em>Escherichia coli</em> (DEC) among outpatients in Beijing, and to analyse the antimicrobial susceptibility profiles and antimicrobial resistance gene characteristics of the isolated strains.</div></div><div><h3>Methods</h3><div>From 2021 to 2024, DEC strains were collected from outpatient specimens. After isolation and identification, the minimum inhibitory concentration (MIC) method was used to assess their susceptibility to 16 antibiotics. Whole-genome sequencing was conducted for further analysis.</div></div><div><h3>Results</h3><div>Among the 1209 DEC strains, the highest resistance rates were observed for ampicillin (63.28%) and tetracycline (45.57%). In contrast, significantly lower rates were found for tigecycline (0.41%), amikacin (0.66%), meropenem (3.97%), ertapenem (6.70%), ceftazidime (7.20%), and ciprofloxacin (9.26%). The 0–5 age group demonstrated higher resistance rates to most antibiotics compared with other age groups. Multi-locus sequence typing revealed significant genetic diversity among all strains, with the predominant sequence types identified as ST10 (5.96%), ST1491 (5.21%), ST4 (4.22%), and ST48 (3.47%). Among 111 fluoroquinolone-resistant strains, chromosomal mutations in <em>gyrA</em> and <em>parC</em> genes were predominant (56.76%). Among 612 cephalosporin-resistant isolates, the <em>bla</em>_CTX−M gene was the most prevalent resistance gene (30.72%).</div></div><div><h3>Conclusions</h3><div>DEC infections and the spread of resistance genes pose a significant health threat, especially in children. Consequently, there is an urgent need to enhance the surveillance and research of resistance genes and to promote the rational use of antibiotics.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"47 ","pages":"Pages 1-8"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146040836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic epidemiology of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in Mwanza, Tanzania","authors":"Vitus Silago ,&nbsp;Benson R. Kidenya ,&nbsp;Katarina Oravcova ,&nbsp;Louise Matthews ,&nbsp;Conjester I. Mtemisika ,&nbsp;Stephen E. Mshana ,&nbsp;Heike Claus ,&nbsp;Jeremiah Seni","doi":"10.1016/j.jgar.2026.01.010","DOIUrl":"10.1016/j.jgar.2026.01.010","url":null,"abstract":"<div><h3>Background</h3><div>Extended-spectrum beta-lactamase-producing <em>Escherichia coli</em> (ESBL-EC) and <em>Klebsiella pneumoniae</em> (ESBL-KP) represent major clinical threats globally. Genomic epidemiological data remain scarce in low- and middle-income countries, limiting a comprehensive understanding of antimicrobial-resistant pathogen diversity and clonal distribution. The present study investigated the genomic epidemiology of ESBL-EC and ESBL-KP isolates in Mwanza, Tanzania.</div></div><div><h3>Methods</h3><div>This cross-sectional hospital-based study employed whole-genome sequencing to characterise ESBL-EC (<em>n</em> = 39) and ESBL-KP (<em>n</em> = 49) isolated from patients with bloodstream, urinary tract, and wound infections at a zonal referral hospital between June 2019–June 2020 and March–August 2023.</div></div><div><h3>Results</h3><div>Thirteen sequence types (STs) were identified among ESBL-EC, predominantly ST131 (30.7%) and ST648 (28.2%). ESBL-KP comprised 15 STs, with ST2390 (24.5%) and ST17 (18.4%) being the most common. The <em>bla</em>_CTX−M-15 gene was detected in 87.2% of ESBL-EC and 95.9% of ESBL-KP. IncFII was the dominant plasmid replicon in ESBL-EC (63.9%) and ESBL-KP (83.7%), while repB was detected exclusively in ESBL-KP (28.6%), particularly among ST2390. ESBL-EC showed significantly higher resistance to ciprofloxacin (<em>P</em> &lt; 0.01), whereas ESBL-KP demonstrated higher resistance to gentamicin and piperacillin-tazobactam (both <em>P</em> &lt; 0.01). The cgMLST-based Neighbour-Joining phylogenetic analysis revealed substantial genetic diversity and identified clonal clusters involving the high-risk clone ESBL-EC ST131. Clusters of ESBL-EC ST131 and ST648 were observed across medical and neonatology wards, while ESBL-KP ST2390 clusters were mainly confined to neonatology wards.</div></div><div><h3>Conclusion</h3><div>This study highlights clonal clusters, the first report of ESBL-KP ST2390, and the predominance of the virulent high-risk clone ESBL-EC ST131 in Mwanza, Tanzania. Underscoring the critical need for reinforced infection control strategies and genomic surveillance.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"47 ","pages":"Pages 55-63"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146086035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}