Antibiotics-Basel最新文献

{"title":"Outbreak of NDM-5-Producing <i>Proteus mirabilis</i> During the COVID-19 Pandemic in an Argentine Hospital.","authors":"Barbara Ghiglione, Ana Paula Rodriguez, María Sol Haim, Laura Esther Friedman, Nilton Lincopan, María Eugenia Ochiuzzi, José Alejandro Di Conza","doi":"10.3390/antibiotics14060557","DOIUrl":"10.3390/antibiotics14060557","url":null,"abstract":"<p><p><b>Background:</b> During the COVID-19 pandemic, the emergence of multidrug-resistant (MDR) pathogens, driven by heightened antibiotic usage and device-associated infections, has posed significant challenges to healthcare. This study reports an outbreak of <i>Proteus mirabilis</i> producing NDM-5 and CTX-M-15 β-lactamases in a hospital in Buenos Aires, Argentina, from October 2020 to April 2021. To our knowledge, this represents the first documented outbreak of NDM-5-producing <i>P. mirabilis</i> in the country. <b>Methods:</b> A total of 82 isolates were recovered from 40 patients, with 41.5% from blood cultures and 18.3% from respiratory and urinary samples, among others. Antimicrobial susceptibility testing, PCR-based methods, and MALDI-TOF MS cluster analysis were conducted. Whole genome sequencing (WGS) was performed to characterize the MLST, resistome and plasmid content. Biofilm formation assays and in vitro rifampicin susceptibility tests were also conducted. <b>Result:</b> Most isolates exhibited resistance to carbapenems, cephalosporins, aminoglycosides, and fluoroquinolones, while retaining susceptibility to aztreonam. Genetic analysis confirmed the co-presence of the <i>bla</i>_NDM-5 and <i>bla</i>_CTX-M-15 genes. Clonal relationships was supported by PCR-based typing and MALDI-TOF MS cluster analysis. WGS revealed a resistome comprising 25 resistance genes, including <i>rmtB</i> and both β-lactamases, as well as the presence of an incomplete IncQ1 replicon associated with multiple resistance determinants. MLST classified this clone as belonging to ST135. Despite the biofilm-forming capacity observed across strains, rifampicin demonstrated potential for disrupting established biofilms at concentrations ≥32 µg/mL in vitro. The MDR profile of the outbreak strain significantly limited therapeutic options. <b>Conclusions:</b> This study highlights the growing threat of NDM-producing <i>P. mirabilis</i> in Argentina. The absence of surveillance cultures from the index case limits insights into the outbreak's origin. These findings underscore the importance of integrating genomic surveillance into infection control protocols to mitigate the spread of MDR pathogens.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189985/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hypervirulent <i>Acinetobacter baumannii</i> (hvAB): The Convergence of Virulence and Multidrug Resistance.","authors":"Nan Wu, Xinqian Ma, Wentao Ni","doi":"10.3390/antibiotics14060551","DOIUrl":"10.3390/antibiotics14060551","url":null,"abstract":"<p><p><i>Acinetobacter baumannii</i> has become a formidable pathogen in healthcare systems worldwide, primarily due to its remarkable capacity to develop multidrug resistance and cause life-threatening infections. While traditionally <i>A. baumannii</i> is considered an opportunistic pathogen of low virulence, accumulating evidence now underscores the emergence of hypervirulent <i>A. baumannii</i> (hvAB) strains. These strains combine heightened pathogenicity with extensive drug resistance, posing unprecedented challenges for clinical management and infection containment. This review comprehensively explores the molecular mechanisms driving hvAB's virulence and antimicrobial resistance and its evolutionary trajectory, clinical presentations, and global epidemiology. Additionally, we evaluate potential therapeutic strategies and their broader public health implications.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190087/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144486996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Patterns and Appropriateness of Systemic Antifungal Prescriptions in a Regional Hospital in Hong Kong.","authors":"Ryan Y H Leung, Jimmy Y W Lam","doi":"10.3390/antibiotics14060556","DOIUrl":"10.3390/antibiotics14060556","url":null,"abstract":"<p><strong>Introduction: </strong>The consumption of systemic antifungals is on the rise. However, a significant proportion of systemic antifungal prescriptions is inappropriate. Inappropriately prescribed antifungals are problematic, but there has been minimal emphasis on ensuring the appropriate prescription of systemic antifungals. Local studies regarding the patterns and appropriateness of antifungal prescriptions are also lacking.</p><p><strong>Materials and methods: </strong>In this retrospective, single-centre, observational study, every in-patient prescription order of systemic antifungals in a regional hospital in Hong Kong between 1 May and 31 July 2023 was reviewed via electronic patient records. The appropriateness of a systemic antifungal prescription was assessed by its indication, dosage, duration and antifungal-concomitant drug interactions by a single reviewer.</p><p><strong>Results: </strong>A total of 177 prescriptions orders were collected. Itraconazole, micafungin and fluconazole were the most prescribed systemic antifungals. The haematology team, infectious disease team and ICU were the major systemic antifungal prescribers in this study. The overall appropriateness of systemic antifungal prescriptions was 27.7% (49/177), with an appropriateness of 72.9% (129/177) for indications, 57.1% (101/177) for dosage, 91.5% (162/177) for duration and 71.6% (127/177) for antifungal-concomitant drug interactions. Triazole antifungals had an overall prescription appropriateness of only 15% and were more likely to be prescribed inappropriately than non-triazole antifungals (<i>p</i> < 0.001). Common prescription pitfalls include (i) starting a systemic antifungal for sputum culture that grew <i>Candida</i> spp., (ii) debatable prophylaxis with itraconazole capsules, (iii) overlooking potentially serious antifungal-drug interactions.</p><p><strong>Conclusions: </strong>Inappropriate systemic antifungal prescription is not uncommon in Hong Kong. Establishing an antifungal stewardship programme in public hospitals may be beneficial.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189983/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mutation of <i>smeRv</i> Renders <i>Stenotrophomonas maltophilia</i> Resistant to First-Line Antibiotics Trimethoprim/Sulfamethoxazole and Levofloxacin.","authors":"Nuchjaree Boonyong, Nisanart Charoenlap, Parinya Tipanyo, Pitthawat Grittanaanun, Skorn Mongkolsuk, Paiboon Vattanaviboon","doi":"10.3390/antibiotics14060550","DOIUrl":"10.3390/antibiotics14060550","url":null,"abstract":"<p><p><b>Background:</b><i>Stenotrophomonas maltophilia</i> is one of the common causative agents of hospital-acquired infections worldwide. The major concern regarding <i>S. maltophilia</i> infections is its extreme resistance to multiple antibiotics. <b>Methods:</b> Enrofloxacin-resistant mutants of <i>S. maltophilia</i> K279a were selected using a serial passage technique. <b>Results:</b> In this study, we showed that one of the mutant strains, KE507, which was selected from <i>S. maltophilia</i> K279a for its resistance to the veterinary drug enrofloxacin, conferred resistance to trimethoprim/sulfamethoxazole (co-trimoxazole), levofloxacin, and minocycline as per the Clinical and Laboratory Standards Institute guideline. These antibiotics are the first-line drugs routinely used to treat <i>S. maltophilia</i> infections. The KE507 mutant also showed increased resistance to all tested quinolones, azithromycin, and neomycin. Molecular characterization using whole genome sequencing, antibiotic resistance gene expression profiles, and mutational analysis indicated that inactivation of SmeRv (Q208insHSPRFTW), a transcriptional regulator of the SmeVWX multidrug efflux pump, contributes to resistance to quinolones (including levofloxacin), co-trimoxazole, and partially to neomycin, but not to azithromycin or minocycline. These data, together with in silico structural analysis, suggest that the mutation of SmeRv causes a conformational change in the SmeRv structure, which leads to the activation of SmeVWX efflux transporter expression and subsequent resistance to co-trimoxazole and quinolone antibiotics. <b>Conclusion:</b><i>S. maltophilia</i> can thus acquire resistance to the antibiotics primarily used to treat <i>S. maltophilia</i> infections through the mutation of SmeRv.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibacterial Activity of Some Essential Oils/Herbal Extracts Against Bacteria Isolated from Ball Pythons (<i>Python regius</i>) with Respiratory Infections.","authors":"Corina Pascu, Viorel Herman, Luminita Costinar, Corina Badea, Valentin Gros, Georgeta Stefan","doi":"10.3390/antibiotics14060549","DOIUrl":"10.3390/antibiotics14060549","url":null,"abstract":"<p><strong>Background: </strong>Respiratory diseases are among the main causes of morbidity and mortality in captive reptiles. In Romania, pneumonia is a frequently observed illness affecting pet reptiles. Key factors contributing to the high incidence of pneumonia include inadequate animal husbandry, poor nutrition, and insufficient hygiene practices. Bacteria may act as primary pathogens or as facilitators of disease severity.</p><p><strong>Methods: </strong>This study investigates bacterial strains from multiple genera and species (<i>Chryseobacterium</i> (<i>C.</i>) <i>indologenes</i>, <i>Staphylococcus</i> (<i>S.</i>) <i>epidermidis</i>, <i>Escherichia</i> (<i>E.</i>) <i>coli</i>, and <i>Pseudomonas</i> (<i>P.</i>) <i>aeruginoasa</i>) from six ball pythons regarding their antibiotic susceptibility and the effect of essential oils. Bacteria were isolated from the lower respiratory tract, displaying clinical signs of pneumonia. All isolates were tested with essential oils (lemongrass, oregano, rosemary, and sage) and a grapefruit seed extract (GSE) at different dilutions.</p><p><strong>Results: </strong>The incidence of <i>Chryseobacterium indologenes</i> was highest (3 isolates/12 samples, 25%), followed by <i>E. coli</i> and <i>Staphylococcus epidermidis</i> (2/12 each, 16.6%), and <i>Pseudomonas aeruginoasa</i> (1/12, 8.3%). Resistance profiling to different antibiotic classes revealed that all isolates (eight) were resistant to multiple antibiotics tested by us. All isolates were resistant to β-lactams and fluoroquinolones. One strain of <i>E. coli</i> exhibited intermediate resistance to quinolone and penicillin. All strains were categorized as multidrug-resistant. GSE showed antibacterial activity against all isolates.</p><p><strong>Conclusions: </strong>Wanting to deepen our understanding of the microorganisms that can infect ball pythons and recognizing that all isolated bacteria have zoonotic potential, this paper highlights some common issues faced by exotic animal owners and suggests that treatments should also include the use of essential oils.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189463/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring Plasma Concentrations of Intravenously Administered Fosfomycin to Prevent Drug-Related Adverse Events: A Retrospective Observational Study.","authors":"Kathrin Marx, Nina Malmström, Marie Quast, Annette Glas, Ralph Wendt, Martina Kinzig, Fritz Sörgel, Maike Fedders, Thilo Bertsche, Christoph Lübbert","doi":"10.3390/antibiotics14060548","DOIUrl":"10.3390/antibiotics14060548","url":null,"abstract":"<p><p><b>Background:</b> Fosfomycin is used as a combination partner for the treatment of severe non-urinary tract infections. Individualized dosing of fosfomycin based on therapeutic drug monitoring (TDM) has the potential to reduce drug-related adverse events (AEs). <b>Methods:</b> This retrospective study used routine data from patients receiving intravenous fosfomycin therapy. Plasma concentrations of fosfomycin were categorized into three different ranges: <64 mg/L, 64-128 mg/L, and >128 mg/L. Subsequently, the influence of acute kidney injury (AKI) on reaching the specific plasma concentration ranges and the occurrence of AEs was analyzed. <b>Results:</b> The study included 143 patients (median age 73 years, 66.4% male) with fosfomycin plasma measurements. Beta-lactam antibiotics were most frequently used in combination (62.2%), followed by tetracyclines (12.2%), cotrimoxazole (8.1%), and other agents (17.5%). Fosfomycin concentrations were >128 mg/L in 45% (36/80) of patients with normal renal function, 70.4% (38/54) of patients with AKI stages I to III, and 77.8% (7/9) of patients with renal replacement therapy. AEs occurred in 54% (77/143), mainly hypernatremia (42.6%), hypokalemia (39.9%), and gastrointestinal symptoms (19.6%), with the median fosfomycin plasma concentration being significantly higher in patients with AEs (158 mg/L vs. 131 mg/L, <i>p</i> = 0.01). Multivariate logistic regression analysis revealed that patients aged ≥70 years (OR 3.70, 95% CI 1.24-11.5; <i>p</i> = 0.02) and patients with fosfomycin plasma concentrations > 128 mg/L (OR 3.30, 95% CI 1.09-10.4; <i>p</i> = 0.04) had a higher risk of AEs. <b>Conclusions:</b> There was a significant association between high plasma exposure and the occurrence of AEs. In particular, the impact of acute renal insufficiency on fosfomycin plasma concentrations should be considered. Individualized fosfomycin dosing based on TDM and the intensive monitoring of renal function contribute to reducing drug-related side effects.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189526/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial Peptides: An Emerging Hope in the Era of New Infections and Resistance.","authors":"Piyush Baindara","doi":"10.3390/antibiotics14060546","DOIUrl":"10.3390/antibiotics14060546","url":null,"abstract":"<p><p>Recently, antimicrobial peptides (AMPs) have garnered significant attention as a viable alternative to traditional antibiotics [...].</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189473/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vaccination with a Live Avirulent <i>E. coli</i> Vaccine Resulted in Improved Production Performance Combined with a Significant Reduction in Antimicrobial Use.","authors":"Frédéric Vangroenweghe, Thomas Matthijs, Marnix Sinnaeve","doi":"10.3390/antibiotics14060547","DOIUrl":"10.3390/antibiotics14060547","url":null,"abstract":"<p><strong>Background/objectives: </strong>In swine production, the post-weaning period has been identified as one of the most challenging and stressful periods in the life of a piglet due to changes in its environment and feeding regimen. During this period, piglets might undergo infectious challenges with enterotoxigenic <i>Escherichia coli</i> (ETEC) resulting in post-weaning diarrhea (PWD), and meningitis due to <i>Streptococcus suis</i>. Therefore, metaphylactic and curative antimicrobial therapy is frequently applied, which leads to an increased treatment incidence per 100 days at risk (TI₁₀₀).</p><p><strong>Methods: </strong>Here, we report the results of an antimicrobial coaching trajectory in a 1000-sow farm with high antimicrobial use during the post-weaning period. For a period of 21 weeks, we evaluated the effect of an oral live avirulent <i>E. coli</i> F4F18 vaccine (Coliprotec^® F4F18; Elanco AH) for the active immunization of piglets against PWD caused by F4- and F18-ETEC on the reduction in antimicrobial use during the post-weaning period. A 1000-sow farm with PIC sows operating in a 1-week BMS was rated as an 'attention farm' at the level of the post-weaning period according to the Antimicrobial Consumption and Resistance in Animals (AMCRA) benchmark reporting tool. To analyze the specific approach towards antimicrobial use and the related post-weaning pathology, a farm visit including a biosecurity check was carried out together with all associated stakeholders. Subsequently, an antimicrobial coaching trajectory was utilized to follow-up on the improvement of the reduction in antimicrobial use after implementation of the various pieces of advice.</p><p><strong>Results: </strong>For analytical purposes, we compared the results obtained in period 1 (P1; vaccination week 1-6) to period 2 (P2; vaccination week 7-21), since practical field experience has demonstrated that a 'stabilization period' of about 6 weeks is necessary to obtain the maximal effect of vaccination. There was a significant reduction in mortality (5.7% to 2.0%) and improvement in the average daily weight gain (366 g/d to 392 g/d) following vaccination, with a simultaneous reduction in the number of days in nursery (45 days to 38 days). Meanwhile, the weight at the end of nursery remained at a similar level. There was a clinically relevant though non-significant decrease in the TI₁₀₀ (32.8 days to 20.6 days). Overall, the implementation of all measures resulted in a positive ROI of 2.72 per piglet.</p><p><strong>Conclusions: </strong>The implementation of several biosecurity measures in combination with the use of an oral live avirulent <i>E. coli</i> F4F18 vaccine (Coliprotec F4F18) could improve performance parameters and reduce mortality, while reducing the number of days in nursery and the TI₁₀₀. Overall, a positive return on investment of 2.72 could be obtained per piglet produced under these improved conditions.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189581/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Current Landscape of Phage-Antibiotic Synergistic (PAS) Interactions.","authors":"Brittany S I Supina, Jonathan J Dennis","doi":"10.3390/antibiotics14060545","DOIUrl":"10.3390/antibiotics14060545","url":null,"abstract":"<p><p><b>Background:</b> In response to the urgent need for new antibiotics targeting high-priority MDR pathogens, bacteriophages (phages) have emerged as promising non-traditional antimicrobial agents. Phages are viruses that infect bacteria and induce cell lysis through mechanisms distinct from those of antibiotics, making them largely unaffected by most antibiotic resistance mechanisms. Importantly, phages have been shown to work cooperatively with an array of clinically useful antibiotics, and phage-antibiotic synergy (PAS) represents a sophisticated strategy that may improve treatment outcomes. However, the interactions between phages and antibiotics are diverse, ranging from synergistic to antagonistic, and understanding the mechanisms underlying these interactions is crucial for developing effective PAS treatments. In this review, we summarize the potential evolutionary and molecular mechanisms that drive PAS and the current landscape of phage-antibiotic interactions. <b>Conclusions</b>: Towards the development of robust PAS strategies, we review in vitro methods for assessing PAS and considerations for choosing and employing candidate phage-antibiotic combinations.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190067/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activity of β-Lactamase Inhibitor Combinations Against Enterobacterales Isolated from Patients with Intra-Abdominal Infection from United States Medical Centres (2019-2023).","authors":"Helio S Sader, John H Kimbrough, Marisa L Winkler, Rodrigo E Mendes, Mariana Castanheira","doi":"10.3390/antibiotics14060544","DOIUrl":"10.3390/antibiotics14060544","url":null,"abstract":"<p><p><b>Objective</b>: To evaluate the antimicrobial susceptibility of Enterobacterales isolated from patients with intra-abdominal infections (IAI) in United States (US) medical centres. <b>Methods</b>: A total of 2036 isolates (1/patient) were consecutively collected from patients with IAI in 63 US hospitals in 2019-2023 and susceptibility tested by broth microdilution. Carbapenem-resistant Enterobacterales (CRE) were screened for carbapenemases by whole genome sequencing. <b>Results</b>: The most common Enterobacterales species were <i>E. coli</i> (47.1%), <i>K. pneumoniae</i> (18.7%), and <i>E. cloacae</i> species complex (9.8%). The most active agents were aztreonam-avibactam (MIC_50/90, ≤0.03/0.12 mg/L), ceftazidime-avibactam (MIC_50/90, 0.12/0.25 mg/L), and meropenem-vaborbactam (MIC_50/90, 0.03/0.06 mg/L) with 99.9% susceptibility. A multidrug-resistant (MDR) phenotype (nonsusceptibility to ≥3 classes) was observed in 21.4% of Enterobacterales (<i>n</i> = 436). Piperacillin-tazobactam was active against 87.2% of Enterobacterales overall and 50.2% of MDR isolates, and meropenem was active against 99.2% of Enterobacterales and 96.1% of MDR isolates. Only 51.6% of Enterobacterales were susceptible to ampicillin-sulbactam. An acquired broad-spectrum β-lactamase gene was identified in 207 (10.2%) isolates and included extended-spectrum β-lactamases (ESBL; <i>n</i> = 182), transferable AmpC (<i>n</i> = 24) and carbapenemases (<i>n</i> = 9). Eight isolates produced two β-lactamase classes. <b>Conclusions</b>: Aztreonam-avibactam, ceftazidime-avibactam, and meropenem-vaborbactam exhibited almost complete activity (99.9% susceptibility) against Enterobacterales causing IAI in US hospitals. In contrast, piperacillin-tazobactam exhibited limited activity against these organisms, especially those with a MDR phenotype.</p>","PeriodicalId":54246,"journal":{"name":"Antibiotics-Basel","volume":"14 6","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12189872/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144487065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}