Journal of global antimicrobial resistance最新文献

{"title":"Ceftazidime-avibactam resistance in Klebsiella pneumoniae: A growing public health concern across diverse sublineages, 2019–2024","authors":"Ana Beatriz Gonçalves ,&nbsp;Valquíria Alves ,&nbsp;Isabel Neves ,&nbsp;Antónia Read ,&nbsp;Luísa Peixe ,&nbsp;Ângela Novais","doi":"10.1016/j.jgar.2025.06.016","DOIUrl":"10.1016/j.jgar.2025.06.016","url":null,"abstract":"<div><h3>Objectives</h3><div>Strains resistant to last-line β-lactam antibiotics pose a global public health threat, requiring close monitoring and action. This study investigated ceftazidime-avibactam (CAZ-AVI) resistance rates among <em>Klebsiella pneumoniae</em> infection isolates from northern Portugal in a 6-year period.</div></div><div><h3>Methods</h3><div>A total of 539 carbapenem-resistant or KPC-positive <em>K. pneumoniae</em> isolates identified between May 2019 and February 2024 were screened for CAZ-AVI resistance by gradient diffusion. Species identification and antimicrobial susceptibility testing were performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and VITEK 2 automated systems, respectively. CAZ-AVI resistance and extended susceptibility profiles were confirmed by disk diffusion. Isolates exhibiting resistance or reduced susceptibility to CAZ-AVI were further characterized by Fourier-transform infrared spectroscopy and whole genome sequencing or polymerase chain reaction and sequencing.</div></div><div><h3>Results</h3><div>We observed an average CAZ-AVI resistance rate of 1.7%, which increased post-COVID19 (1.1% in 2021 to 2.7% in 2022) alongside rising CAZ-AVI usage. Notably, CAZ-AVI-resistant isolates also exhibited resistance to last-line β-lactams not yet introduced in routine clinical practice (89% cefiderocol, 33% imipenem-relebactam and 22% meropenem-vaborbactam). Resistance to CAZ-AVI was associated with production of diverse KPC-3 variants (KPC-31, KPC-46, KPC-66), IMP-22 or DHA-1 often in combination with porin deficiencies. A multiclonal population was identified, including high-risk sublineages commonly linked to KPC-3 production (ST147-KL64 and ST323-KL21). All patients had prior exposure to different β-lactams, including CAZ-AVI in five cases.</div></div><div><h3>Conclusions</h3><div>Our findings highlight a concerning scenario for managing carbapenem-resistant <em>K. pneumoniae</em> and underscore the need for routine laboratory testing of last-line antibiotics and the implementation of effective antimicrobial stewardship guidelines.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 211-216"},"PeriodicalIF":3.7,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528261","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":"Need for antifungal stewardship in critically ill cancer patients: A pilot study from a tertiary hospital in Eastern India","authors":"Soumyadip Chatterji ,&nbsp;Victor Franchi ,&nbsp;Sanjay Bhattacharya ,&nbsp;Sudipta Mukherjee ,&nbsp;Pralay Shankar Ghosh ,&nbsp;Amit Yadav ,&nbsp;Priya Ghosh ,&nbsp;Argha Chatterjee","doi":"10.1016/j.jgar.2025.06.018","DOIUrl":"10.1016/j.jgar.2025.06.018","url":null,"abstract":"<div><h3>Objective</h3><div>The increasing incidence of invasive fungal infections (IFIs) in critically ill and immunocompromised populations, particularly in India, challenges antifungal management. Rising resistance and high ICU burden of invasive candidiasis and mould infections underscore the need for antifungal stewardship (AFS). This study evaluated AFS needs in the ICU of a tertiary oncology centre in Eastern India by assessing antifungal prescription appropriateness.</div></div><div><h3>Methods</h3><div>A prospective pilot study was conducted from 12–31 August 2024, in the ICU/high dependency unit of an oncology/haematology hospital in Eastern India. All patients receiving systemic antifungals (SAF) were included. Appropriateness of SAF prescriptions, diagnostic workup and regimen modifications were assessed based on predefined criteria validated by external experts. Data were collected at SAF initiation and on day 5 or at discharge, whichever occurred first.</div></div><div><h3>Results</h3><div>Among 25 patients (median age 56 years, interquartile range 49–64; 68% female; 80% solid cancers), SAF was empiric in 76%, targeted in 16% and prophylactic in 8%. Prescription appropriateness was optimal in 55%, suboptimal in 15% and inappropriate in 30%. Loading doses were administered in 85%. Diagnostic workup was insufficient in 75% of suspected invasive pulmonary aspergillosis (IPA) and 83% of invasive candidiasis (IC) cases. No SAF was discontinued within 5 d, and only 10% of patients had regimen modifications.</div></div><div><h3>Conclusion</h3><div>Empiric antifungal prescriptions were frequently inappropriate, with insufficient diagnostic investigations, particularly for IC. The lack of de-escalation highlights the urgent need for an ICU-specific AFS programme to optimize antifungal use and improve diagnostics in high-risk patients.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 234-240"},"PeriodicalIF":3.7,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528263","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":"OXA-carbapenemases and mutations within PBPs in ST2 carbapenem-resistant A. baumannii: Evaluating the efficacy of cefiderocol and ampicillin-sulbactam combination therapy","authors":"Carlo Tascini ,&nbsp;Simone Giuliano ,&nbsp;Luca Martini ,&nbsp;Novella Carannante ,&nbsp;Bernardo Mariano ,&nbsp;Mariagrazia Perilli ,&nbsp;Alessandra Piccirilli","doi":"10.1016/j.jgar.2025.06.014","DOIUrl":"10.1016/j.jgar.2025.06.014","url":null,"abstract":"<div><h3>Objectives</h3><div>Carbapenem-resistant <em>Acinetobacter baumannii</em> (<em>A. baumannii</em>; CRAB) isolates represent a serious public health concern. Recently, a novel molecule, the cefiderocol (FDC), has emerged as a promising therapeutic option for CRAB infections. In the present study, we analysed the genomes of five <em>A. baumannii</em> ST2 isolates from four hospitalized patients. All patients were treated with FDC and an ampicillin/sulbactam (AMP/SUL) combination.</div></div><div><h3>Methods</h3><div>Whole-genome sequencing of the five CRAB isolates was performed using an Illumina MiSeq instrument. A detailed bioinformatic analysis was carried out to acquire information about genotyping, antimicrobial resistance genes (ARGs), virulence associated genes (VAGs), single nucleotide polymorphisms (SNPs), and the phylogenetic tree of the five CRAB isolates.</div></div><div><h3>Results</h3><div>Among the five CRAB isolates, only three (Ab.2, Ab.3, and Ab.4) exhibited resistance to FDC. The genomes of all isolates were highly similar, and multilocus sequence typing (MLST) analysis indicated they all belong to sequence type 2 (ST2), corresponding to international clone 2. Phylogenetic analysis suggests that isolates Ab.2, Ab.3, and Ab.4 may share a common ancestor or be linked by a possible transmission event. In contrast, isolates Ab.1 and Ab.5 were more divergent from the other three. Nevertheless, all five isolates harboured the same ARGs and VAGs. The OXA-23, OXA-66, and ADC-25 β-lactamases were detected in all strains. The FDC-non-susceptible isolates showed a K235N/H370Y double mutation within PBP3, along with a G370C substitution in PBP1a.</div></div><div><h3>Conclusions</h3><div>The four clinical cases described in this study represent an important example of the efficacy and good practice of FDC plus AMP/SUL combination in the treatment of critical patients suffering from CRAB infections. © 2025 The Author(s). Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 189-196"},"PeriodicalIF":3.7,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528264","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":"Real-world analysis of ceftolozane/tazobactam prescribing patterns and effectiveness: SPECTRA analysis on chronic pulmonary diseases and respiratory-related infections","authors":"Emre Yucel ,&nbsp;Alex Soriano ,&nbsp;David L. Paterson ,&nbsp;Florian Thalhammer ,&nbsp;Stefan Kluge ,&nbsp;Pierluigi Viale ,&nbsp;Mike Allen ,&nbsp;Brune Akrich ,&nbsp;Jessica Levy ,&nbsp;Huina Yang ,&nbsp;Sunny Kaul","doi":"10.1016/j.jgar.2025.06.015","DOIUrl":"10.1016/j.jgar.2025.06.015","url":null,"abstract":"<div><h3>Objectives</h3><div>In hospital settings, both pre-existing antibiotic-resistant Gram-negative (GN) bacteria and those that develop resistance during treatment pose significant challenges, often contributing to significant morbidity and mortality. This study focuses on chronic pulmonary disease (CPD) and respiratory-related infections (RRI), including pneumonia, from SPECTRA study. Understanding the real-world clinical use and outcomes for patients treated with ceftolozane/tazobactam (C/T) is essential.</div></div><div><h3>Methods</h3><div>The multi-national SPECTRA study utilised inpatient chart reviews to describe real-world practice and collect outcome data in hospitalised patients treated with C/T. This analysis focuses on secondary data from SPECTRA cohorts of CPD and RRI patients (the most common conditions comprising RRI included pneumonia and exacerbation of chronic respiratory infection [ECRI]).</div></div><div><h3>Results</h3><div>Between January 2016 and October 2020, 180 patients with CPD, 275 with RRI, 182 with pneumonia, and 91 with ECRI who received C/T for ≥48 h were included. The mean (standard deviation [SD]) age was 57.5 (18.7) years, 55.8 (18.2) years, 57.8 (17.4) years, and 51.8 (19.1) years in CPD, RRI, pneumonia, and ECRI patients, respectively. <em>Pseudomonas aeruginosa</em> was the most frequent pathogen, identified (91.5%, 91.8%, 88.0%, and 97.0% CPD, RRI, pneumonia, and ECRI patients, respectively), with MDR strains in 76.9%, 74.7%, 68.4%, and 80.3% CPD, RRI, pneumonia, and ECRI patients, respectively. Clinical success was achieved in 69.4%, 66.2%, 59.9%, 79.1% of CPD, RRI, pneumonia, and ECRI patients, respectively.</div></div><div><h3>Conclusions</h3><div>This SPECTRA subgroup analysis demonstrates significant real-world utilisation of C/T in treating patients with CPD and RRI, aligning with previous controlled studies.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 217-225"},"PeriodicalIF":3.7,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144511978","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":"Systematic review and meta-analysis of prediction models for multidrug-resistant organism infections in comprehensive intensive care units","authors":"Zai-Chun Pu ,&nbsp;Xiao-Li Wei ,&nbsp;Yan Zhou ,&nbsp;Xiao-Li Liu ,&nbsp;Zi-Ji Fang ,&nbsp;Le-Le Li ,&nbsp;Ping Jia","doi":"10.1016/j.jgar.2025.06.012","DOIUrl":"10.1016/j.jgar.2025.06.012","url":null,"abstract":"<div><h3>Objective</h3><div>To explore the predictive factors for infections caused by multidrug-resistant bacteria and to systematically evaluate risk prediction models for multidrug-resistant bacterial infections in comprehensive intensive care units (ICUs), with the aim of providing references for clinical medical personnel to establish and improve risk prediction models for such infections.</div></div><div><h3>Methods</h3><div>A computer search was conducted in Chinese and English database for studies on the construction of risk prediction models for multidrug-resistant bacterial infections in comprehensive ICUs, with the search timeframe from the establishment of the database to 26 December 2024. The quality of the literature was assessed via the Prediction Model Risk Of Bias ASsessment Tool, and meta-analysis was performed via RevMan 5.4 and MedCalc software.</div></div><div><h3>Results</h3><div>Among the 27 articles, 37 risk prediction models were constructed, with area under the receiver operating characteristic curve (AUC) values ranging from 0.718 to 0.992. A quality assessment of the literature indicated a high risk of bias and good applicability. A meta-analysis using MedCalc on AUC values revealed a combined modelling group AUC of 0.867. The meta-analysis revealed 12 risk factors that could predict multidrug-resistant infections.</div></div><div><h3>Conclusions</h3><div>Current risk prediction models for multidrug-resistant bacterial infections in the ICU are still in the developmental stage. Most prediction models lack calibration methods and external validation, and only univariate analysis is used to select variables, resulting in a high risk of bias. Future efforts should focus on improving model construction methods and continuing to develop risk prediction models with higher accuracy.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 139-145"},"PeriodicalIF":3.7,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144497228","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":"Metagenomic and whole-genome characterization of carbapenem-resistant Acinetobacter baumannii carrying blaOXA-23 gene within the Tn2006 transposon among ICU patients","authors":"Senhong Ying ,&nbsp;Zhirong Zhang ,&nbsp;Rong Xiang","doi":"10.1016/j.jgar.2025.06.009","DOIUrl":"10.1016/j.jgar.2025.06.009","url":null,"abstract":"<div><h3>Purpose</h3><div>To characterize carbapenem-resistant <em>Acinetobacter baumannii</em> carrying <em>bla</em>_OXA-23 genes within the Tn<em>2006</em> transposon using metagenomic and whole-genome sequencing, focusing on their genetic features, antimicrobial resistance, and potential for clonal spread and horizontal gene transfer among intensive care unit (ICU) patients.</div></div><div><h3>Methods</h3><div>Bronchoalveolar lavage fluid samples from 28 ICU patients were analysed using metagenomic next-generation sequencing to detect pathogens and resistance genes. <em>A. baumannii</em> isolates underwent whole-genome sequencing for genetic diversity assessment. Antimicrobial susceptibility testing and comparative genomic analysis were performed.</div></div><div><h3>Results</h3><div>Metagenomic next-generation sequencing revealed mixed infections in 71.4% of patients, identifying multiple bacteria, viruses, fungi, and <em>Mycoplasma</em> species. <em>A. baumannii</em> was detected in 25 samples, often alongside other pathogens. All isolates harboured <em>bla</em>_OXA-23 within Tn<em>2006</em> on the chromosome and belonged to sequence type ST2, indicating clonal dissemination despite significant genetic diversity (up to 2969 single-nucleotide polymorphism differences). The isolates were highly resistant to multiple antibiotics but remained susceptible to tigecycline and colistin. Comparative genomic analysis with 238 global carbapenem-resistant <em>A. baumannii</em> genomes confirmed the prevalence of the Tn<em>2006</em> transposon carrying <em>bla</em>_OXA-23 in ST2 strains, emphasizing the potential for rapid spread of this resistance mechanism.</div></div><div><h3>Conclusions</h3><div>The widespread presence of multidrug-resistant <em>A. baumannii</em> carrying <em>bla</em>_OXA-23 within Tn<em>2006</em> among ICU patients poses a significant public health concern. The high rate of mixed infections and the potential for horizontal gene transfer complicate infection management in critically ill patients. Enhanced infection control measures, continuous surveillance, and targeted interventions are urgently needed to prevent further dissemination of these resistant strains in hospital settings.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 180-185"},"PeriodicalIF":3.7,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144484730","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 activity of sulopenem and comparator agents against US Enterobacterales clinical isolates collected during the SENTRY antimicrobial surveillance program in 2023","authors":"Steven I. Aronin ,&nbsp;Michael D. Huband ,&nbsp;Holly Becker ,&nbsp;Kelley A. Fedler ,&nbsp;Michael W. Dunne","doi":"10.1016/j.jgar.2025.06.013","DOIUrl":"10.1016/j.jgar.2025.06.013","url":null,"abstract":"<div><h3>Objective</h3><div>Sulopenem is a thiopenem antibacterial with an oral and parenteral formulation. Sulopenem etzadroxil/probenecid, the oral formulation, was recently approved by the United States Food and Drug Administration for the treatment of women with uncomplicated urinary tract infection (UTI). This study evaluated the in vitro activity of sulopenem and comparator agents against contemporary Enterobacterales clinical isolates predominantly from patients with UTIs.</div></div><div><h3>Methods</h3><div>A contemporary collection of 1086 community- and nosocomial-acquired Enterobacterales isolates was assembled from US medical centres. Isolates were susceptibility tested using the Clinical and Laboratory Standards Institute broth microdilution reference method.</div></div><div><h3>Results</h3><div>Sulopenem demonstrated potent in vitro antimicrobial activity (MIC_50/90, 0.03/0.25 mg/L) against Enterobacterales isolates regardless of infection type, inhibiting 98.0% of isolates at ≤0.5 mg/L. This activity was conserved against resistant phenotypes, including extended-spectrum β-lactamase (ESBL)-phenotype <em>Escherichia coli</em> (MIC_50/90, 0.03/0.06 mg/L) and ESBL-phenotype <em>Klebsiella pneumoniae</em> (MIC_50/90, 0.06/0.12 mg/L). As would be expected, cross-resistance was found with imipenem and meropenem to a lesser extent. Sulopenem maintained activity against ciprofloxacin-, nitrofurantoin-, and trimethoprim/sulfamethoxazole-non-susceptible subsets, including urinary isolates from patients in the community (MIC_50/90, 0.03–0.12/0.12–0.5 mg/L). Sulopenem also maintained activity against community-acquired ESBL-producing Enterobacterales urinary isolates non-susceptible to two or more oral antimicrobial agents commonly used to treat UTIs.</div></div><div><h3>Conclusions</h3><div>The potent in vitro activity of sulopenem against this large collection of contemporary Enterobacterales clinical isolates from multiple infection types supports its use in the treatment of uncomplicated UTI, as well as its further clinical evaluation in the treatment of other common bacterial infections demonstrating resistant phenotypes.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 152-159"},"PeriodicalIF":3.7,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144484729","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 mcr-1.1-producing Escherichia coli in clinical settings in Tunisia","authors":"Nadia Jaidane ,&nbsp;Thierry Naas ,&nbsp;Sameh Boughattas ,&nbsp;Laetitia Du Fraysseix ,&nbsp;Lamia Tilouche ,&nbsp;Meriem Souguir ,&nbsp;Pauline François ,&nbsp;Wajdi Chermiti ,&nbsp;Abdelhalim Trabelsi ,&nbsp;Jean-Yves Madec ,&nbsp;Wejdene Mansour ,&nbsp;Marisa Haenni","doi":"10.1016/j.jgar.2025.06.011","DOIUrl":"10.1016/j.jgar.2025.06.011","url":null,"abstract":"<div><h3>Objective</h3><div>Our study aims at characterizing a <em>mcr-1</em>-producing <em>Escherichia coli</em> ST224 clinical isolate collected at the University Hospital of Sahloul-Sousse from a joint infection.</div></div><div><h3>Methods</h3><div>Phenotypic characterization was performed using a Vitek-2 System. NGS was performed by short-read (150 bp paired-end reads) sequencing on a NovaSeq6000 platform, as well as by long-read sequencing using an ONT R10.4 flow cell. Hybrid assembly was achieved using the Flye de novo assembler, and analyses were performed using tools of the Center for Genomic Epidemiology. The <em>mcr-1</em>-carrying plasmid was compared by BLAST to similar plasmids recovered in the NCBI database and visualized by PROKSEE.</div></div><div><h3>Results</h3><div>The collected <em>E. coli</em> belonged to ST224 and was multi-drug resistant, remaining susceptible to carbapenems, amikacin, gentamicin, and sulfamethoxazole only. Resistances to last-generation cephalosporins (mediated by <em>bla</em>_CMY-2) and fluoroquinolones were chromosomally-encoded. The <em>mcr-1.1</em> gene was carried by an Inc12 plasmid similar but not identical to published data, and that lacked the two copies of the IS<em>Apl1</em> element usually bracketing the <em>mcr-1.1</em> and <em>pap2</em> genes.</div></div><div><h3>Conclusions</h3><div>The dissemination of plasmid-encoded <em>mcr-1</em> genes that can spread across species and sectors is a major health issue in countries such as Tunisia, where colistin is essential for the treatment of complicated human infections due to carbapenem-resistant Enterobacterales. Reporting all <em>mcr-1</em>-positive <em>E. coli</em> clinical isolates is thus important to understand the dynamic of spread of these resistant pathogens.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 149-151"},"PeriodicalIF":3.7,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144475582","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":"Regulatory role of ISEcp1 and spacer sequences in blaCTX-M–mediated cephalosporin resistance in Shigella","authors":"Hui Zhang ,&nbsp;Shengkun He ,&nbsp;Xiaoying Pang ,&nbsp;Xi He ,&nbsp;Xuechun Liu ,&nbsp;Shaofu Qiu ,&nbsp;Chaojie Yang ,&nbsp;Hongbin Song","doi":"10.1016/j.jgar.2025.06.005","DOIUrl":"10.1016/j.jgar.2025.06.005","url":null,"abstract":"<div><h3>Background</h3><div>Extended-spectrum β-lactamases, especially CTX-M enzymes, play a critical role in cephalosporin resistance in several bacterial species. The IS<em>Ecp1</em> insertion sequence, a mobile genetic element, regulates the high expression and horizontal transfer of the <em>bla</em>_CTX-M gene. Diverse types of spacer regions exist, the length of which varies across the different types of <em>bla</em>_CTX-M genes and their upstream IS<em>Ecp1</em> elements. In this study, we aimed to investigate the distribution and role of IS<em>Ecp1</em> and different length spacers in antibiotic-resistant <em>Shigella</em>.</div></div><div><h3>Methods</h3><div>We selected 1393 cephalosporin-resistant <em>Shigella</em> strains isolated from China between 2004 and 2016 to analyse the distribution of IS<em>Ecp1</em> and spacers using polymerase chain reaction and sequencing. To functionally evaluate the role of these elements, we designed different combinations of IS<em>Ecp1</em>, spacer sequences, and <em>bla</em>_CTX-M gene fragments to generate and express recombinant plasmids containing these fragments in <em>Escherichia coli.</em> We then assessed the cephalosporin resistance phenotype of recombinant clones using the E-TEST method.</div></div><div><h3>Results</h3><div>The carriage rate of IS<em>Ecp1</em> in cephalosporin-resistant <em>Shigella</em> was 90.09%, with an IS<em>Ecp1</em>-CTX-M element carriage rate of 67.19%, and was significantly higher in the <em>bla</em>_CTX-M-9 group than that in the <em>bla</em>_CTX-M-1 group. Moreover, <em>E. coli</em> strains containing different combinations exhibited varying bacterial resistance to β-lactam antibiotics, indicating the regulatory role of IS<em>Ecp1</em> and spacers.</div></div><div><h3>Conclusions</h3><div>Our results demonstrate that the configuration of IS<em>Ecp1</em>, spacer sequences, and <em>bla</em>_CTX-M in plasmids fosters a robust resistance phenotype against various cephalosporins, providing new insights into antimicrobial resistance mechanisms and an important basis for developing novel anti-resistance drugs.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 127-134"},"PeriodicalIF":3.7,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144368917","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 novel ST17306 Escherichia coli Isolate carrying tet(X4) from an infant with bronchopneumonia in China","authors":"Mengting Luo ,&nbsp;Qiao Li ,&nbsp;Fang He ,&nbsp;Zhengquan Yang","doi":"10.1016/j.jgar.2025.06.010","DOIUrl":"10.1016/j.jgar.2025.06.010","url":null,"abstract":"<div><h3>Objectives</h3><div>Despite the widespread occurrence of <em>tet</em>(X4)-mediated tigecycline resistance in <em>Escherichia coli</em> from animal and environmental sources, its presence in human clinical isolates remains rare. In this study, we report the first whole-genome sequence of a <em>E. coli</em> isolate harboring <em>tet</em>(X4) and belonging to a novel sequence type, recovered from an infant in China.</div></div><div><h3>Methods</h3><div>The complete genome of <em>E. coli</em> Q65 was sequenced using a combination of Illumina NovaSeq 6000 and Oxford Nanopore MinION sequencing platforms. Functional annotation was conducted using the NCBI Prokaryotic Genome Annotation Pipeline (PGAP), and genomic features were further analyzed with a range of bioinformatics tools.</div></div><div><h3>Results</h3><div>The genome of <em>E. coli</em> strain Q65 is 5 442 192 bp in length and encodes 5089 proteins. Strain Q65 was classified as sequence type ST17306, a novel member of the ST69 clonal complex, and was assigned the serotype O17:H18. Q65 exhibited multidrug resistance, carrying 14 antimicrobial resistance genes, including <em>tet</em>(X4). The <em>tet</em>(X4) gene was located on a 192 048 bp hybrid plasmid belonging to the IncFIA(HI1)/IncHI1B(R27)/IncHI1A replicon types. A search of the NCBI database revealed similar <em>tet</em>(X4)-carrying hybrid plasmids present in various <em>Enterobacteriaceae</em> species, suggesting that such plasmids may play a key role in mediating the horizontal transfer of <em>tet</em>(X4).</div></div><div><h3>Conclusion</h3><div>This study presents the first complete genome sequence of a <em>tet</em>(X4)-positive, multidrug-resistant <em>E. coli</em> strain belonging to the novel sequence type ST17306, isolated from a Chinese infant with bronchopneumonia. Continuous global surveillance of the dissemination of <em>tet</em>(X4)-harboring strains is crucial to monitor and control the potential public health threat.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":"44 ","pages":"Pages 146-148"},"PeriodicalIF":3.7,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144368916","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}