Journal of global antimicrobial resistance最新文献

{"title":"Wastewater-based AMR surveillance associated with tourism on a Caribbean island (Guadeloupe).","authors":"Mélanie Pimenta, Maria Alexa, Degrâce Batantou Mabandza, Sylvain Dulaurent, Bich-Tram Huynh, Margaux Gaschet, Lulla Opatowski, Sébastien Breurec, Marie-Cécile Ploy, Christophe Dagot","doi":"10.1016/j.jgar.2025.03.010","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.010","url":null,"abstract":"<p><strong>Background: </strong>Antimicrobial resistance (AMR) is a major public health concern worldwide. International travel is a risk factor for acquiring antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs). Therefore, understanding the transmission of ARB and ARGs is instrumental in tackling AMR. This longitudinal study aimed to assess the benefit of wastewater monitoring in Guadeloupe to evaluate the role of tourism in the spread of AMR.</p><p><strong>Methods: </strong>A wastewater-based surveillance (WBS) study was conducted to monitor AMR in Guadeloupe in 2022 during dry and wet seasons. We characterized the resistome, microbiome and exposome of water samples collected in wastewater treatment facilities of two cities with different levels of tourism activities, in the content of aircraft toilets, and the pumping station receiving effluents from hotels.</p><p><strong>Results: </strong>The results show that the WBS approach facilitates the differentiation of various untreated effluents concerning exposome, microbiome, and resistome, offering insights into AMR dissemination. Additionally, the findings reveal that microbiome and exposome are comparable across sites and seasons, while resistome characterisation at specific locations may be pertinent for health surveillance. The microbiome of aircraft was predominantly composed of anaerobic bacteria from human intestinal microbiota, whereas the other locations exhibited a blend of human and environmental bacteria. Notably, individuals arriving by air have not introduced clinically significant resistance genes. Exposome compounds have been shown to influence the resistome's variance.</p><p><strong>Conclusion: </strong>Clear differences were seen between the aircraft and the local sampling sites, indicating that the contribution of tourism to the observed resistance in Guadeloupe is not significant.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743031","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":"Fecal microbiota transplantation to decolonize vancomycin-resistant Enterococcus: A pilot study to evaluate safety and clinical outcome.","authors":"Shu-Min Lin, Puo-Hsien Le, Chyi-Liang Chen, Yuan-Ming Yeh, Hsien-Li Liao, Cheng-Hsun Chiu","doi":"10.1016/j.jgar.2025.03.011","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.011","url":null,"abstract":"<p><strong>Objectives: </strong>Fecal microbiota transplantation (FMT) has shown promise as a treatment for recurrent or refractory Clostridioides difficile infections. This study aimed to evaluate the decolonization effects of FMT on vancomycin-resistant Enterococcus (VRE).</p><p><strong>Methods: </strong>This feasibility trial prospectively recruited patients with more than three recurrent VRE infections. FMT was performed by infusing fecal microbiota solutions from healthy, unrelated donors into the participants' guts via colonoscopy. Fecal microbiota profiles before and after FMT were analyzed.</p><p><strong>Results: </strong>Three of the six patients (50%) experienced VRE decolonization after FMT, lasting over six months. Baseline analysis revealed that patients who achieved decolonization had greater microbial diversity compared to those with persistent VRE colonization. Throughout the study, there were no adverse events observed in the patients after FMT. Elevated alpha diversity persisted in responders, while non-responders showed no significant changes. In responders, the abundance of genera within the phylum Firmicutes (Bacillota), including Anaerostipes, Blautia, Faecalibacterium, and Ruminococcus, and the genus Collinsella within the phylum Actinobacteriota increased steadily through 180 days post-FMT.</p><p><strong>Conclusions: </strong>FMT may leverage bacterial strain competition to facilitate decolonization of drug-resistant organisms, with successful VRE decolonization potentially linked to increased abundance of phyla Firmicutes and Actinobacteriota over 6 months.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743026","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":"Clostridium Butyricum Miyairi Bacteriocin Treatment for Clostridioides difficile Infections with Clinical Isolates: Insights from In Vitro, Ex Vivo, and Mouse Model Studies.","authors":"Ching-Chi Lee, Yi-Chen Tu, Hung-Tsung Wu, Wen-Chien Ko, Hsiao-Chieh Liu, Pei-Jane Tsai, Hsiang-Ning Chang, I-Hsiu Huang, Yuan-Pin Hung","doi":"10.1016/j.jgar.2025.03.007","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.007","url":null,"abstract":"<p><strong>Objective: </strong>The standard antimicrobial therapy for Clostridioides difficile infections (CDIs) is limited to oral fidaxomicin or vancomycin, but these agents are associated with high treatment failure and recurrence rates. Clostridium butyricum had been proven effective in many kinds of gastrointestinal disease. With a less disturbed gut microbiota, we hypothesized that the properties of Clostridium butyricum Miyairi Bacteriocin (CBM-B) make it a potential therapeutic agent for treating patients with CDIs.</p><p><strong>Methods: </strong>The inhibitory effects of CBM-B and vancomycin were compared using the kinetic time-kill assay, ex vivo co-culture model and mouse model.</p><p><strong>Results: </strong>Among the clinical isolates of C. difficile, the minimal inhibitory concentration (MIC) of CBM-B ranged from 0.0625 to 8 µg/ml; the MIC₅₀ and MIC₉₀ were 1 µg/ml and 4 µg/ml, respectively. In the mouse model infected with a RT078 and receiving CBM-B intra-rectal enema therapy, mice infected with isolates with a relative low CBM-B MICs (2 µg/ml, abbreviated as M2) revealed significant better therapeutic effect, including less loss of body weight and cecum weight, compared with those infected with isolates of relative high CBM-B MICs (4 or 8 µg/ml, abbreviated as M4 or M8) . The relative C. difficile bacterial burden in stool of mice receiving CBM-B treatment were significantly lower among mice infected with M2, compared with that infected with M4 or M8. CBMB treatment, compared with vancomycin therapy revealed less disturbance in gut microbiota.</p><p><strong>Conclusion: </strong>CBM-B could be effective in the treatment of CDIs that infected with a C. difficile isolate with relatively low MICs with less disturbance in gut microbiota.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730345","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":"Characterization of a Multidrug-Resistant Hypovirulent ST1859-KL35 Klebsiella quasipneumoniae subsp. similipneumoniae Strain Co-harboring tmexCD2-toprJ2 and bla_KPC-2.","authors":"Jiawei Ding, Mengying Zhang, Jiyong Chang, Zidan Hu, Pei He, Jia Wang, Lei Feng","doi":"10.1016/j.jgar.2025.03.009","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.009","url":null,"abstract":"<p><strong>Objectives: </strong>The rise of multidrug-resistant (MDR) Klebsiella pneumoniae is a significant public health threat. Klebsiella quasipneumoniae is often misidentified as K. pneumoniae, and its genetic and virulence traits remain underexplored. This study characterizes the genomic and phenotypic features of a K. quasipneumoniae subsp. similipneumoniae strain (KP24) .</p><p><strong>Methods: </strong>Antibiotic susceptibility was tested using microbroth dilution assay. Virulence was evaluated through serum killing assay and Galleria mellonella infection model. Whole genome sequencing (WGS) and bioinformatics analysis determined sequence typing, resistance profiles, and plasmid types. Conjugation assays assessed plasmid transferability, while phylogenetic analysis explored genetic relationships.</p><p><strong>Results: </strong>KP24 exhibited an MDR phenotype, including resistance to carbapenems, ceftazidime/avibactam, and tigecycline. KP24 showed significantly higher serum survival and G. mellonella lethality than ATCC700603, though it was less virulent than the hypervirulent strain NUTH-K2044. WGS identified KP24 as ST1859 and KL35, harboring the aerobactin virulence gene cluster (iucABCDiutA) and multiple resistance genes, including tmexCD2-toprJ2, bla_KPC-2, bla_OXA-10, bla_IMP-4, and qnrS1. Notably, the tmexCD2-toprJ2 and bla_KPC-2 genes were located on the same plasmid (pKP24-1) , an uncommon co-existence. Conjugation assays confirmed the independent transferability of pKP24-1 to Escherichia coli J53. Phylogenetic analysis revealed that ST1859 forms a distinct monoclade with low genetic diversity, closely related to ST334, suggesting regional expansion and potential global dissemination.</p><p><strong>Conclusions: </strong>KP24 represents a hypovirulent yet multidrug-resistant strain of K. quasipneumoniae subsp. similipneumoniae, with a concerning combination of virulence and resistance determinants. The co-location of tmexCD2-toprJ2 and bla_KPC-2 on a transferable plasmid highlights the potential for horizontal gene transfer of critical resistance mechanisms.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669928","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":"Characterization of bla_NDM-5-bearing IncHI2 plasmid from Escherichia fergusonii in China.","authors":"Yan Shi, Yue Yang, Yu Song, Yujie Zhu, Guoping Zhao, Biao Tang","doi":"10.1016/j.jgar.2025.03.008","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.008","url":null,"abstract":"<p><strong>Objectives: </strong>Carbapenems are considered to be the last resort to the serious infections caused by multidrug-resistant (MDR) Gram-negative bacteria. The emergence of carbapenem-resistant Enterobacteriaceae has posed serious threat to human health. However, carbapenem resistance is rarely reported in E. fergusonii. In this study, an NDM-5 producing E. fergusonii strain EFSXRJ10 was isolated from chicken in China.</p><p><strong>Methods: </strong>The minimal inhibitory concentrations (MICs) were determined using broth microdilution-based antimicrobial susceptibility testing. The complete genome sequence of the NDM-positive isolate was obtained through Illumina NovaSeq and Oxford Nanopore GridION sequencing platforms, followed by hybrid assembly with Unicycler. In the plasmid conjugation assay, the sodium azide-resistant E. coli strain J53 was employed as the recipient.</p><p><strong>Results: </strong>Strain EFSXRJ10 was resistant to ampicillin, amoxycillin-Clavulanic acid, gentamicin, spectinomycin, tetracycline, florfenicol, sulfafurazole, cefotaxime, ceftazidime, apramycin and meropenem. The bla_NDM-5 gene was located on the IncHI2 plasmid. This plasmid can be transferred by conjugation at a frequency of (4.78 ± 0.67) × 10^-5. The bla_NDM-5-carrying plasmid which harboring 14 antibiotic resistance genes belonged to IncHI2/ST3 type and exhibited high similarity to other bla_NDM-5-carrying IncHI2 plasmids deposited in GenBank. The genetic structure surrounding bla_NDM-5 was organized as \"IS3000-ΔISAba125-IS5-ΔISAba125-bla_NDM-5-ble_MBL-trpF-dsbD-IS26-∆umuD-∆ISKox3-∆IS3000\".</p><p><strong>Conclusions: </strong>This is the first report on the characterization of bla_NDM-5-bearing IncHI2 plasmid in E. fergusonii. Surveillance and control measures should be implemented to arrest the transmission of bla_NDM-5 from food animals.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669932","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":"Whole genome sequencing characterization of the new KPC-245 variant-carrying Klebsiella pneumoniae strain isolated from a transplanted patient and resistant to ceftazidime/avibactam, meropenem/vaborbactam and imipenem/relebactam.","authors":"Claudia Vaiana, Roberta Vazzana, Salvatore Castelbuono, Andrea Cona, Alessandra Mularoni, Rita Minucci, Francesco Monaco, Daniele Di Carlo, Pier Giulio Conaldi, Alessia Gallo, Nicola Cuscino","doi":"10.1016/j.jgar.2025.03.006","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.006","url":null,"abstract":"<p><strong>Objectives: </strong>Across recent decades the increasing prevalence of multi-drug resistant KPC-carrying K. pneumoniae (KPC-Kp) has become a worldwide public concern. Herein, we characterized a ceftazidime/avibactam (CAZ/AVI), meropenem/vaborbactam (MER-VAB) and imipenem/relebactam (IMI-REL) resistant KPC-Kp strain isolated from a critically ill transplanted patient.</p><p><strong>Methods: </strong>Antimicrobial susceptibility test and whole-genome sequencing (WGS) were conducted to characterize the strain at the phenotypic and the genotypic levels. Genomic DNA was sequenced using the Illumina platform. Bioinformatic analyses were used to investigate the genome sequences both for resistance and virulence features, and for characterization of plasmids.</p><p><strong>Results: </strong>The phenotypic characterization revealed that the KPC-Kp isolate was highly resistant to a wide range of antibiotics, including all the beta-lactam/beta lactamase inhibitor combinations, such as CAZ/AVI, MER-VAB, IMI-REL, and cefiderocol (FDC). WGS analysis showed that the isolate, belonging to the rare lineage ST661, contained several resistance and virulence genes. Among the resistance genes, we identified a new KPC variant, inside the mobile genetic element Tn4401, KPC-245, characterized by an insertion of 9 aminoacids (RAPNKDDYT) at position 263 and an aminoacidic change E274D of the protein sequence, compared to KPC-3. Interestingly, the presence of mutations only in bla_KPC gene, and not in other beta-lactamases coding genes, strongly points KPC-245 role in beta-lactam/beta-lactamase inhibitor combinations and FDC resistance.</p><p><strong>Conclusions: </strong>In our study, by using WGS analysis on a clinical isolate, we identified a new bla_KPC variant inside the Tn4401 transposon. Our results confirm the important role of the continuous surveillance of MDR K. pneumoniae in the clinical context.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669946","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":"Draft genome of the multidrug-resistant Citrobacter freundii strain CAPA023 isolated from Arapaima gigas in Peru: is it a reservoir of resistance and virulence genes?","authors":"Enrique Garcia-Candela, Aaron Mondragón-Martínez, Manuel Noceda-Rodríguez, Fernando Mesias Valle, Milagros Cabrera-Soregui, Veronica Valverde-Vera, Maria Benito-García, Romina Romayna-Ríos, Miriam Verástegui-Tello, Saurabh Dubey, Hetron M Munang'andu, Jefferson Yunis-Aguinaga","doi":"10.1016/j.jgar.2025.03.005","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.005","url":null,"abstract":"<p><strong>Objectives: </strong>The purpose of this study was to analyze the genome of the multidrug-resistant Citrobacter freundii strain CAPA023, which was obtained from diseased Arapaima gigas fry. The study focused on determining mobile genetic elements and genetic factors that contribute to antibiotic resistance and pathogenicity.</p><p><strong>Methods: </strong>Genomic DNA was sequenced using Illumina NovaSeq (2 × 150 bp) and assembled de novo using Shovill v1.1.0. Resistance genes, virulence factors, plasmids, and mobile elements were identified using ResFinder, CARD, PlasmidFinder, MobileFinder, PathogenFinder, and VFDB.</p><p><strong>Results: </strong>The 5,059,550 bp draft genome (60 contigs, 51.5% GC) revealed resistance genes for various antibiotic classes, efflux pumps, IncFIB(K) and Col440I plasmids, insertion sequences, and multiple virulence genes.</p><p><strong>Conclusion: </strong>Considering that this bacterium was found in diseased fish, it is possible that C. freundii plays an important role in the spread of virulence factors and antibiotic resistance in aquaculture environments. This highlights the importance of genomic surveillance in Amazonian aquaculture.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143624933","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":"Progress and challenges in the implementation of Antimicrobial Stewardship Programs in 50 hospitals in Mexico.","authors":"Anahí Dreser, Jennifer Hegewisch-Taylor, María Alejandra Cortés-Ortiz, Gabriel Levy Hara","doi":"10.1016/j.jgar.2025.02.018","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.02.018","url":null,"abstract":"<p><strong>Objectives: </strong>;Antimicrobial stewardship programs (ASP) aim to improve the quality of medical prescribing and contain antimicrobial resistance (AMR). There is little information on the implementation of ASP in hospitals in Mexico. This study aimed to characterize ASP in a sample of hospitals in Mexico and to identify the facilitators and barriers perceived in their implementation, including the COVID-19 pandemic.</p><p><strong>Methods: </strong>;A self-assessment electronic survey was adapted from the CDC and WHO ASP's core elements, considering ASP organization, structure, education, guidelines, interventions, surveillance, monitoring, and reporting processes. The survey was addressed to ASP team leaders in a sample of public and private hospitals carrying out regular antimicrobial stewardship activities in Mexico in 2021 and 2022.</p><p><strong>Results: </strong>;Fifty hospitals participated: 32 (64%) public and 18 (36%) private. Fifty-two percent of hospitals had an official ASP document, 12% allocated protected time for ASP professionals, and 34% had an annual plan. Most hospitals had an ASP committee (68%); only 14% allocated funding. Most interventions were restrictive (68%). 61% percent of hospitals prepared cumulative antibiograms periodically, 54% monitored antimicrobial consumption (DDD/DOT), 44% monitored adherence to guidelines, and 24% monitored the implementation of interventions. The main barriers identified were work overload, insufficient human resources, and hospital reconversion due to COVID-19 (particularly in public hospitals), while the support of hospital authorities was the most important facilitator.</p><p><strong>Conclusions: </strong>;This diagnosis provides a baseline for strengthening ASP implementation in the country's hospitals. National and institutional policies should prioritize targeting ASP planning, monitoring, and human resources allocation.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615634","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":"Epidemiology, Phylogeny and Genetic Characterization of Carbapenem-resistant Citrobacter spp. from 5 hospitals in China.","authors":"Qiang Zhao, Ling Guo, Kun Ye, Lifeng Wang, Jiyong Yang, Liyan Ye","doi":"10.1016/j.jgar.2025.03.003","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.003","url":null,"abstract":"<p><strong>Objectives: </strong>Carbapenem-resistant Citrobacter spp. (CRC) are increasingly recognized as healthcare-associated pathogens, while systematic studies on clinical epidemiology, genetic diversity, and resistant mechanisms of CRC are relatively scarce. The present study provides comprehensive and systematic research on CRC.</p><p><strong>Methods: </strong>Clinical isolates of Citrobacter spp. resistant to carbapenems were collected from 5 hospitals across China between October 2014 and December 2017. All the isolates were identified by MALDI-TOF MS and FastANI. Whole-genome sequencing and phylogenetic analyses were performed. Sequencing data were analyzed using MLST, PlasmidFinder, ResFinder, and ISFinder tools.</p><p><strong>Results: </strong>Thirty-one CRC isolates were isolated from 5 hospitals in different provinces. These strains exhibited significant phylogenetic divergence. ST85 (12.90%) and ST116 (12.90%) were the predominant STs. NDM (41.94%), KPC-2 (25.81%), and IMP (19.35%) were the most frequent carbapenemases of CRC. Interestingly, KPC is frequently associated with C. freundii, while NDM is predominantly observed in C. portucalensis. All the IncX3 and IncN-type plasmids carrying bla_NDM- and most non-type plasmids carrying bla_KPC- were transferrable by conjugation. The genes bla_NDM and bla_KPC were primarily located within relatively conserved genomic environments, including \"ISAba125-bla_NDM-ble_MBL-trpF-dsbD-cutA1-groES-groEL-ISCR27\" and \"Tn3 transposase-ISKpn27-bla_KPC-2-△ISKpn6-korC-kclA-hp-hp-△repB-TnAS1\".</p><p><strong>Conclusions: </strong>The clonal transmission of CRC and the conjugative antibiotic resistance plasmids were the key mechanisms driving the spread of multidrug resistance. It highlights the need to strengthen molecular surveillance, with a focus on high-prevalence clones such as ST85 and ST116 carrying mobile resistance elements.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615670","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":"Characterization of Klebsiella pneumoniae Carbapenemase (KPC)-14, a KPC Variant Conferring Resistance to Ceftazidime-Avibactam in the Extensively Drug-resistant ST463 Pseudomonas aeruginosa Clinical Isolate.","authors":"Yanyan Xiao, Le Wang, Huiqiong Jia, Yan Jiang, Yue Li, Jiamin Han, Shengchao Li, Yaxi Gu, Qing Yang","doi":"10.1016/j.jgar.2025.03.004","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.03.004","url":null,"abstract":"<p><strong>Objectives: </strong>We studied two Klebsiella pneumoniae carbapenemase (KPC)-14 variants from clinical Pseudomonas aeruginosa isolates (C137 and C159) to better understand the genomic diversity, mechanisms, and genes that confer antibiotic resistance and pathogenicity.</p><p><strong>Methods: </strong>Genomic DNA from C137/159 was subjected to Illumina and Oxford Nanopore sequencing. Horizontal transmission of the plasmid was evaluated using cloning experiments. The expression of efflux pumps, the outer membrane protein OprD, and the enzyme AmpC was quantified using qRT-PCR. The detectability of KPC-14 was evaluated using different methods, and biofilm formation assays and growth curves were assessed.</p><p><strong>Results: </strong>C137 and C159, sequence type 463 ExoU-positive multidrug-resistant strains, were concurrently resistant to carbapenems and ceftazidime-avibactam (CZA). Both strains possessed five intrinsic antimicrobial resistance genes (fosA, catB7, crpP, bla_PAO, and a bla_OXA-486 variant) as well as bla_KPC-14. In strain C137, bla_KPC-14 was located on a plasmid (pC137). Both strains expressed the bla_KPC-14 gene, concurrent inactivation of OprD, overexpression of the MexX efflux pump, and a pronounced capacity for biofilm formation. The genomic environment of KPC-14 consisted of IS26/IS26/TnpR_Tn3/ISKpn27/ISKpn6/IS26, which classified it as pseudo-compound transposon (PCT). IS26-mediated PCTs may store a variety of resistance genes, including bla_KPC-2 and KPC variants, which are currently disseminating in this region.</p><p><strong>Conclusion: </strong>The KPC-14 variant presents significant challenges for clinical treatment. The bla_KPC-14 gene carried by PCTs was integrated into the chromosome and exhibited stability throughout bacterial inheritance. Our research highlights the need for improved clinical surveillance of KPC-producing P. aeruginosa.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615669","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}