Journal of global antimicrobial resistance最新文献

{"title":"Antibiotic resistance characterization, virulence factors and molecular characteristics of Bacillus species isolated from probiotic preparations in China.","authors":"Xin Jin, Ling Zhang, Yu Cao, Zhen Dai, Xiaoming Ge, Rui Cai, Ruirong Wang, Ziyan Hu","doi":"10.1016/j.jgar.2024.06.015","DOIUrl":"https://doi.org/10.1016/j.jgar.2024.06.015","url":null,"abstract":"<p><strong>Objectives: </strong>The aim of this study was to determine the phenotypic and molecular characteristics of antibiotic-resistant Bacillus spp. isolated from probiotic preparations in China.</p><p><strong>Methods: </strong>Bacillus strains were isolated from probiotic preparations and then identified using 16S rDNA sequencing. Drug sensitivity tests were conducted to determine their susceptibility to seven antibiotics. Whole genome sequencing was performed on the most resistant strains, followed by analysis of their molecular characteristics, resistance genes, and virulence factors.</p><p><strong>Results: </strong>In total, we isolated 21 suspected Bacillus species from seven compound probiotics, which were identified by 16S rDNA as 12 Bacillus licheniformis, six Bacillus subtilis and three Bacillus cereus. The determination of antimicrobial susceptibility showed widespread resistance to chloramphenicol (95.2%), erythromycin (85.7%) and gentamicin (42.9%). Whole genome sequencing of seven resistant strains revealed that J-6-A (Bacillus subtilis) and J-7-A (Bacillus cereus) contained a plasmid. The resistance gene analysis revealed that each strain contained more than ten resistance genes, among which J-7-A was the most. The streptomycin resistance gene strA was detected in all strains. The chloramphenicol resistance genes ykkC and ykkD were found in J-1-A to J-5-A and were first reported in Bacillus subtilis. The erythrocin resistance gene ermD was detected in strains J-1-A to J-4-A. There were also more than 15 virulence factors and gene islands (GIs) involved in each strain.</p><p><strong>Conclusions: </strong>These results confirm the potential safety risks of probiotics and remind us to carefully select probiotic preparations containing strains of Bacillus species, especially Bacillus cereus, to avoid the potential spread of resistance and pathogenicity.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141600227","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":"Clonal expansion of Tn1546-like transposon-carrying vancomycin-resistant Enterococcus faecium, a nationwide study in Taiwan, 2004-2018","authors":"","doi":"10.1016/j.jgar.2024.06.005","DOIUrl":"10.1016/j.jgar.2024.06.005","url":null,"abstract":"<div><h3>Objectives</h3><div>The prevalence of vancomycin-resistant <em>Enterococcus faecium</em> (VREfm) has increased significantly in Taiwan. We investigated the molecular epidemiology of clinical VREfm isolates to increase our understanding on their spread and changes in population structure over a 14-year span.</div></div><div><h3>Methods</h3><div>A total of 1113 <em>E. faecium</em> isolates were collected biennially from 2004 to 2018 in Taiwan. MICs were determined by broth microdilution. Whole-genome sequencing (WGS) was performed on 229 VREfm isolates to characterize their genetic environment of vancomycin resistance and wgMLST was used to investigate their clonal relationship.</div></div><div><h3>Results</h3><div>Among the 229 isolates, ST17 and ST78 predominated, especially during the later years, and their prevalences increased from 14.6% (7/48) and 25.0% (12/48) in 2004–2010 to 47.5% (87/181) and 29.8% (54/181) in 2012–2018, respectively. Four types of <em>vanA</em>-carrying Tn<em>1546</em> variants were detected, with type 1 and type 2 predominated. Type 1 Tn<em>1546</em> contained an addition of IS<em>1251</em>, while type 2 resembled type 1 but had an addition of IS<em>1678</em>. wgMLST revealed several distinct clusters of ST17 and ST78 isolates, with type 1 Tn<em>1546</em>-harbouring ST17-Cluster 16 being the largest and most widespread clones throughout the study years. Type 2 Tn<em>1546</em>-carrying ST78 became a predominant clone (Cluster 21) after 2012. Isolates within these clusters are highly similar despite being from different hospitals, regions, and study year.</div></div><div><h3>Conclusion</h3><div>The increase of VREfm in Taiwan was attributed to horizontal transfer of <em>vanA</em>-carrying Tn<em>1546</em> variants between different STs and spread of persistent clones. This study highlights the importance of integrating WGS into surveillance to combat antimicrobial resistance.</div></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141600228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic characterization of plasmid-borne colistin resistance variants, mcr-1.1 and mcr-1.26, in multidrug-resistant Escherichia coli isolated from backyard farm animals","authors":"","doi":"10.1016/j.jgar.2024.06.009","DOIUrl":"10.1016/j.jgar.2024.06.009","url":null,"abstract":"","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001206/pdfft?md5=c1052db4b7c20019fe5ad2300f96260a&pid=1-s2.0-S2213716524001206-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141537920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Favourable effect of clavulanic acid on the minimum inhibitory concentrations of cefixime and ceftibuten in ESBL-producing Escherichia coli and Klebsiella pneumoniae","authors":"","doi":"10.1016/j.jgar.2024.06.008","DOIUrl":"10.1016/j.jgar.2024.06.008","url":null,"abstract":"<div><h3>Objectives</h3><p>The use of cephalosporins combined with clavulanate for the treatment of ESBL-harbouring Enterobacteriaceae has been scarcely described. We aimed to describe the effect of different concentrations of clavulanate in the MIC of cefixime and ceftibuten of ESBL-producing <em>Escherichia coli</em> and <em>Klebsiella pneumoniae</em>.</p></div><div><h3>Methods</h3><p>ESBL-producing <em>E. coli</em> and <em>K. pneumoniae</em> isolates were studied. Fixed concentrations of cefixime and ceftibuten (ranges of 32–0.25 and 64–0.5 ng/ml, respectively) were used. Combinations of cefixime/clavulanate and ceftibuten/clavulanate in different ratios (1:0, 1:1, 2:1, 4:1, 8:1, 16:1, 32:1) were tested. MIC were determined by broth microdilution.</p></div><div><h3>Results</h3><p>A total of 6 ESBL-producing <em>E. coli</em>, 6 ESBL-producing <em>K. pneumoniae</em> and 2 control <em>E. coli</em> were tested. When different quantities of clavulanate were added to cefixime and ceftibuten, greater than two-fold decreases in the MIC were observed. When testing the 1:1 cefixime/clavulanate ratio, 10/12 isolates were susceptible. When the ratios 2:1, 4:1, 8:1 and 16:1 were tested, susceptibility was noted for 9/12, 8/12, 4/12 and 5/12 isolates, respectively. Only 2/12 <em>K. pneumoniae</em> isolates were susceptible when the ratio 32:1 was tested. When testing ceftibuten/clavulanate, all isolates remained susceptible across all experiments.</p></div><div><h3>Conclusions</h3><p>Clavulanic acid has a favourable effect in reducing the MIC of cefixime and ceftibuten in isolates of ESBL-producing <em>E. coli</em> and <em>K. pneumoniae</em>. Combining clavulanate with ceftibuten or cefixime could be a useful treatment strategy.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S221371652400119X/pdfft?md5=937c1a660d7e4927e67f76fcf5a94a65&pid=1-s2.0-S221371652400119X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141468571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Susceptibility evaluation of novel beta-lactam/beta-lactamase inhibitor combinations against carbapenem-resistant Klebsiella pneumoniae from bloodstream infections in hospitalized patients in Brazil","authors":"","doi":"10.1016/j.jgar.2024.06.007","DOIUrl":"10.1016/j.jgar.2024.06.007","url":null,"abstract":"<div><h3>Introduction</h3><p>Novel beta-lactam/beta-lactamase inhibitor (BIBLI) combinations are commercially available and have been used for treating carbapenem-resistant <em>Klebsiella pneumoniae</em> (CRKP) infections. Continuous surveillance of susceptibility profiles and resistance mechanism identification are necessary to monitor the evolution of resistance within these agents.</p></div><div><h3>Objective</h3><p>The purpose of this study was to evaluate the susceptibility rates of ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam in CRKP isolated from patients with bloodstream infections who underwent screening for a randomized clinical trial in Brazil.</p></div><div><h3>Methods</h3><p>Minimum inhibitory concentrations (MICs) were determined for meropenem, ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam using the gradient diffusion strip method. Carbapenemase genes were detected by multiplex real-time polymerase chain reaction. <em>Klebsiella pneumoniae</em> carbapenemase (KPC)-producing isolates showing resistance to any BLBLI and New Delhi Metallo-beta-lactamase (NDM)-producing isolates with susceptibility to any BLBLI isolates were further submitted for whole-genome sequencing.</p></div><div><h3>Results</h3><p>From a total of 69 CRKP isolates, 39 were positive for <em>bla</em>_KPC, 19 for <em>bla</em>_NDM and 11 for <em>bla</em>_KPC and <em>bla</em>_NDM. KPC-producing isolates demonstrated susceptibility rates above 94 % for all BLBLIs. Two isolates with resistance to meropenem/vaborbactam demonstrated a Gly and Asp duplication at the porin OmpK36 as well as a truncated OmpK35. All NDM-producing isolates, including KPC and NDM coproducers, demonstrated susceptibility rates to ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam of 0 %, 9.1–21.1 % and 9.1–26.3 %, respectively. Five NDM-producing isolates that presented susceptibility to BLBLIs also had porin alterations</p></div><div><h3>Conclusions</h3><p>This study showed that, although high susceptibility rates to BLBLIs were found, KPC-2 isolates were able to demonstrate resistance probably as a result of porin mutations. Additionally, NDM-1 isolates showed susceptibility to BLBLIs in vitro.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001188/pdfft?md5=6b3ae468b939456fbf4e6ae87fb82c05&pid=1-s2.0-S2213716524001188-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141468573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Suboptimal bioinformatic predictions of antimicrobial resistance from whole-genome sequences in multidrug-resistant Corynebacterium isolates","authors":"","doi":"10.1016/j.jgar.2024.06.006","DOIUrl":"10.1016/j.jgar.2024.06.006","url":null,"abstract":"<div><p>Herein, we combined different bioinformatics tools and databases (BV-BRC, ResFinder, RAST, and KmerResistance) to perform a prediction of antimicrobial resistance (AMR) in the genomic sequences of 107 <em>Corynebacterium striatum</em> isolates for which trustable antimicrobial susceptibility (AST) phenotypes could be retrieved. Then, the reliabilities of the AMR predictions were evaluated by different metrics: area under the ROC curve (AUC); Major Error Rates (MERs) and Very Major Error Rates (VMERs); Matthews Correlation Coefficient (MCC); F1-Score; and Accuracy. Out of 15 genes that were reliably detected in the <em>C. striatum</em> isolates, only <em>tetW</em> yielded predictive values for tetracycline resistance that were acceptable considering Food and Drug Administration (FDA)’s criteria for quality (MER &lt; 3.0% and VMER with a 95% C.I. ≤1.5–≤7.5); this was accompanied by a MCC score higher than 0.9 for this gene. Noteworthy, our results indicate that other commonly used metrics (AUC, F1-score, and Accuracy) may render overoptimistic evaluations of AMR-prediction reliabilities on imbalanced datasets. Accordingly, out of 10 genes tested by PCR on additional multidrug-resistant <em>Corynebacterium</em> spp. isolates (<em>n</em> = 18), the <em>tetW</em> gene rendered the best agreement values with AST profiles (94.11%). Overall, our results indicate that genome-based AMR prediction can still be challenging for MDR clinical isolates of emerging <em>Corynebacterium</em> spp.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001164/pdfft?md5=2282045f6ecc521bf6b6ed90ce6868df&pid=1-s2.0-S2213716524001164-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141468572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative strategies against superbugs: Developing an AI-CDSS for precise Stenotrophomonas maltophilia treatment","authors":"","doi":"10.1016/j.jgar.2024.06.004","DOIUrl":"10.1016/j.jgar.2024.06.004","url":null,"abstract":"<div><h3>Objectives</h3><p>The World Health Organization <em>named Stenotrophomonas maltophilia</em> (SM) a critical multi-drug resistant threat, necessitating rapid diagnostic strategies. Traditional culturing methods require up to 96 h, including 72 h for bacterial growth, identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) through protein profile analysis, and 24 h for antibiotic susceptibility testing. In this study, we aimed at developing an artificial intelligence-clinical decision support system (AI-CDSS) by integrating MALDI-TOF MS and machine learning to quickly identify levofloxacin and trimethoprim/sulfamethoxazole resistance in SM, optimizing treatment decisions.</p></div><div><h3>Methods</h3><p>We selected 8,662 SM from 165,299 MALDI-TOF MS-analysed bacterial specimens, collected from a major medical centre and four secondary hospitals. We exported mass-to-charge values and intensity spectral profiles from MALDI-TOF MS .mzML files to predict antibiotic susceptibility testing results, obtained with the VITEK-2 system using machine learning algorithms. We optimized the models with GridSearchCV and 5-fold cross-validation.</p></div><div><h3>Results</h3><p>We identified distinct spectral differences between resistant and susceptible SM strains, demonstrating crucial resistance features. The machine learning models, including random forest, light-gradient boosting machine, and XGBoost, exhibited high accuracy. We established an AI-CDSS to offer healthcare professionals swift, data-driven advice on antibiotic use.</p></div><div><h3>Conclusions</h3><p>MALDI-TOF MS and machine learning integration into an AI-CDSS significantly improved rapid SM resistance detection. This system reduced the identification time of resistant strains from 24 h to minutes after MALDI-TOF MS identification, providing timely and data-driven guidance. Combining MALDI-TOF MS with machine learning could enhance clinical decision-making and improve SM infection treatment outcomes.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001139/pdfft?md5=6f8ab4db3e8e5f4719e61107d8ebd613&pid=1-s2.0-S2213716524001139-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141442818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro activity of ceftolozane/tazobactam against Gram-negative bacilli isolated from pediatric patients: Results from the Study for Monitoring Antimicrobial Resistance Trends (SMART) 2017–2021, China","authors":"","doi":"10.1016/j.jgar.2024.05.017","DOIUrl":"10.1016/j.jgar.2024.05.017","url":null,"abstract":"<div><h3>Objectives</h3><p>Ceftolozane-tazobactam (C/T) is a combination of a cephalosporin and a β-lactamase inhibitor with activity against Gram-negative bacilli (GNB). The study aims were to evaluate the activity of C/T in vitro vs. comparators against clinical GNB isolated from Chinese paediatric patients.</p></div><div><h3>Methods</h3><p>From 2017–2021, 660 GNB isolates were collected from 20 hospitals across China. The minimum inhibitory concentrations were tested using a Trek Diagnostic System (Thermo Fisher Scientific). Susceptibility was determined by CLSI broth microdilution and the results were interpreted according to CLSI M100 (2021) breakpoints.</p></div><div><h3>Results</h3><p>GNB isolates were obtained from paediatric patients &lt; 18 years old, mainly from the bloodstream (<em>n</em> = 146), intraperitoneal cavity (<em>n</em> = 138), lower respiratory (<em>n</em> = 278) and urinary tract (<em>n</em> = 96). Overall, C/T was active against 76.6% of 436 Enterobacterales, with a descending susceptibility rate of 100.0% to <em>S. marcescens</em>, 92.2% to <em>E. coli</em>, 83.3% to <em>K. oxytoca</em>, 66.7% to <em>K. aerogenes</em>, 66.7% to <em>P. mirabilis</em>, 58.6% to <em>K. pneumoniae</em> and 57.1% to <em>E. cloacae</em>. The susceptibility of <em>P. aeruginosa</em> to C/T was 89.4%, which was the highest among the β-lactam antibiotics and was second only to amikacin (92.9%). Isolates of respiratory tract infection (RTI) derived <em>P. aeruginosa</em> were highly susceptible (93.8%) to C/T, while &lt;75% of isolates of RTI derived <em>P. aeruginosa</em> were susceptible to the other β-lactam antibiotics tested, except for ceftazidime-avibactam (91.2%).</p></div><div><h3>Conclusion</h3><p>GNBs collected from paediatric patients in China showed a high susceptibility to C/T making this drug combination an effective choice for treating the paediatric population, especially those infected with <em>P. aeruginosa</em>.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001073/pdfft?md5=a0776fd59d993832166afe2e0e936ff1&pid=1-s2.0-S2213716524001073-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141440571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-life experience with IV dalbavancin in Canada; results from the CLEAR (Canadian LEadership on Antimicrobial Real-life usage) registry","authors":"George Zhanel ,&nbsp;Michael Silverman ,&nbsp;Janhavi Malhotra ,&nbsp;Melanie Baxter ,&nbsp;Reza Rahimi ,&nbsp;Neal Irfan ,&nbsp;Gabriel Girouard ,&nbsp;Rita Dhami ,&nbsp;Melissa Kucey ,&nbsp;Vida Stankus ,&nbsp;Kristin Schmidt ,&nbsp;Sébastien Poulin ,&nbsp;William Connors ,&nbsp;Carlo Tascini ,&nbsp;Andrew Walkty ,&nbsp;James Karlowsky","doi":"10.1016/j.jgar.2024.06.002","DOIUrl":"10.1016/j.jgar.2024.06.002","url":null,"abstract":"<div><h3>Objectives</h3><p>We report the use of IV dalbavancin in Canadian patients using data captured by the national CLEAR registry.</p></div><div><h3>Methods</h3><p>The CLEAR registry uses the web-based data management program, REDCap™ (online survey <span>https://rcsurvey.radyfhs.umanitoba.ca/surveys/?s=TPMWJX98HL</span><svg><path></path></svg>) to facilitate clinicians entering details associated with their clinical experiences using IV dalbavancin.</p></div><div><h3>Results</h3><p>Data were available for 40 patients. The most common infections treated were acute bacterial skin and skin structure infection (ABSSSI) (62.5% of patients), bone/joint infection (22.5%), bloodstream/vascular infection (7.5%) and endocarditis (5.0%). Dalbavancin was used as directed (75.0%) and empiric therapy (25.0%). MRSA was the most common identified pathogen (70.0%). Dalbavancin was used both in outpatient (e.g., emergency department) (65.0%), and inpatient treatment settings (e.g., hospital ward) (35.0%). Dalbavancin was used due to the convenience of a single dose treatment (77.5%) as well as to facilitate hospital discharge (7.5%). Dalbavancin was primarily used alone (90.0%), and most commonly using a single 1500 mg dose (77.5%). Microbiological success (pathogen eradicated or presumed eradicated) occurred in 88.2% of known cases, while clinical success (cure and/or improvement) occurred in 93.3% of known cases. No adverse events were reported.</p></div><div><h3>Conclusions</h3><p>In Canada, IV dalbavancin is used as both directed and empiric therapy to treat ABSSSI as well as off-label (bone/joint, bacteremia/vascular, endocarditis, device-related) infections. It is used in both outpatient and inpatient settings due primarily to its convenience as a single-dose treatment regimen and to facilitate early hospital discharge. Dalbavancin use is associated with high microbiological and clinical cure rates along with an excellent safety profile.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001140/pdfft?md5=5e8b8877e4041899366ae7302986570c&pid=1-s2.0-S2213716524001140-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141440572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fitness cost of tet(A) type I variant-mediated tigecycline resistance in Klebsiella pneumoniae","authors":"Yuanyuan Li ,&nbsp;Tianyu Wang ,&nbsp;Yunbing Li ,&nbsp;Chen Xu ,&nbsp;Tianyi Wang ,&nbsp;Lili Huang ,&nbsp;Xiangkun Zeng ,&nbsp;Guangfen Zhang ,&nbsp;Chunli Li ,&nbsp;Ning Dong","doi":"10.1016/j.jgar.2024.06.003","DOIUrl":"10.1016/j.jgar.2024.06.003","url":null,"abstract":"<div><h3>Objective</h3><p>The aim of the present study is to explore the impact of the <em>tet</em>(A) type I variant (<em>tet</em>A-v1) on its fitness effect in <em>Klebsiella pneumoniae</em>.</p></div><div><h3>Methods</h3><p>Clinical <em>K. pneumoniae</em> strains were utilized as parental strains to generate strains carrying only the plasmid vector (pBBR1MCS-5) or the <em>tet</em>A-v1 recombinant plasmid (p<em>tet</em>A-v1). Antimicrobial susceptibility testing was conducted to estimate the contribution of <em>tet</em>A-v1 to drug resistance. Plasmid stability was evaluated by serial passage over 10 consecutive days in the absence of tigecycline. Biological fitness was examined through growth curve analysis, <em>in vitro</em> competition assays and a neutropenic mouse thigh infection model.</p></div><div><h3>Results</h3><p>A 2–4-fold increase in tigecycline MIC was observed following the acquisition of <em>tet</em>A-v1. Without tigecycline treatment, the stability of p<em>tet</em>A-v1 plasmids has been decreasing since day 1. The p<em>tet</em>A-v1 plasmid in Kp89, Kp91, and Kp93 exhibited a decrease of about 20% compared to the pBBR1MCS-5 plasmid. The acquisition of the <em>tet</em>A-v1 gene could inhibit the growth ability of <em>K. pneumoniae</em> strains both <em>in vitro</em> and <em>in vivo. tet</em>A-v1 gene imposed a fitness cost in <em>K. pneumoniae</em>, particularly in the CRKP strain Kp51, with a W value of approximately 0.56.</p></div><div><h3>Conclusion</h3><p>The presence of <em>tet</em>A-v1 is associated with a significant fitness cost in <em>K. pneumoniae</em> in the absence of tigecycline, both <em>in vitro</em> and <em>in vivo</em>.</p></div>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213716524001127/pdfft?md5=9704661f616749c4b4ac6f959c89237e&pid=1-s2.0-S2213716524001127-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141327523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}