Journal of Antimicrobial Chemotherapy最新文献

{"title":"Strengthening antimicrobial resistance diagnostics in National Reference Laboratories across One Health in South and Southeast Asia: impact of external quality assessment and targeted follow-up.","authors":"Freshwork Ayalew Abegaz, Hiba Al-Mir, Tomislav Kostyanev, Kristi Prifti, Soo-Young Kwon, Tobin Guarnacci, Lone Brink Rasmussen, Mohammad Julhas Sujan, Patrícia Teixeira Dos Santos, Rangsiya Prathan, Taradon Luangtongkum, Pattrarat Chanchaitong, Pitak Santanirand, Watcharaporn Kamjumpho, Ondari D Mogeni, Marianne Holm, Florian Marks, Rungtip Chuanchuen, Rene S Hendriksen, Nimesh Poudyal","doi":"10.1093/jac/dkaf266","DOIUrl":"10.1093/jac/dkaf266","url":null,"abstract":"<p><strong>Objectives: </strong>The intent of this study was to evaluate and improve microbiology laboratory diagnostic capacity in selected National AMR Reference laboratories from South and Southeast Asia for AMR testing utilizing EQA and targeted follow-up support.</p><p><strong>Methods: </strong>A baseline assessment was conducted to evaluate quality management system (QMS) practices for laboratories participating in the Strengthening External Quality Assessment in Asia (EQASIA-EQA) programme for the first time. Following each EQA iteration, laboratory assessments were conducted, and underperforming laboratories received online consultations to identify root causes of deviations and implement corrective and preventive actions (CAPA). Laboratories with persistent underperformance, onsite visits and targeted training sessions were provided to support quality improvement.</p><p><strong>Results: </strong>Significant gaps were identified in the QMS of the 24 laboratories surveyed, with 38% lacking a QMS and 42% not conducting internal audits. Many laboratories lacked standard operating procedures (SOPs) for key processes, CAPA and equipment maintenance. Training and competency assessments were insufficient, with 50% of laboratories not conducting competency assessments. Additionally, 46% did not perform root cause analysis for EQA deviations, and 42% lacked a structured quality control programme. Water purity testing and equipment maintenance were also inadequate. Of the four baseline-assessed laboratories, three underperformed twice, and one underperformed three times across EQA iterations. Key deficiencies included the absence of a QMS and SOPs, as well as inadequate staff training and internal quality control. After targeted follow-up support, improvements were observed in QMS implementation, SOP development, staff training and quality control.</p><p><strong>Conclusions: </strong>Participation in EQA, combined with targeted follow-up support, enhances laboratory quality and performance. These improvements ultimately contribute to the provision of reliable data that can guide policy actions to combat AMR.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2541-2549"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12404728/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144731098","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":"Determination of epidemiological cut-off values for Narasin, Salinomycin, Lasalocid and Monensin in Enterococcus faecium.","authors":"Maria Laura Ferrando, Francesca Saluzzo, Rikki Franklin Frederiksen, Jannice Schau Slettemeås, Anne Margrete Urdahl, Roger Simm, Magdalena Skarżyńska, Magdalena Zając, Anna Lalak, Jowita Niczyporuk, Dariusz Wasyl, Léa Duval, Florence Tardy, Claire Schapendonk, Michel Rapallini, Giovanni Tosi, Simona Perulli, Letizia Cirasella, Daniela Maria Cirillo, Mariel G Pikkemaat","doi":"10.1093/jac/dkaf113","DOIUrl":"10.1093/jac/dkaf113","url":null,"abstract":"<p><strong>Objectives: </strong>To establish epidemiological cut-off values (ECOFFs) for the polyether ionophores narasin, salinomycin, lasalocid and monensin in Enterococcus faecium.</p><p><strong>Methods: </strong>MICs were measured using the broth microdilution method according to ISO 20776-1 (2019). Method validation involved ≥10 replicates of antimicrobial susceptibility testing of Enterococcus faecalis ATCC 29212. A total of 182 E. faecium isolates from various sources were tested in five European laboratories. The ECOFFinder tool from EUCAST was used to establish the ECOFFs for 122 WT isolates, verified by PCR or WGS.</p><p><strong>Results: </strong>Method validation showed consistency, with acceptable variation within ±1 2-fold dilution. The ECOFF for narasin was 0.5 mg/L, considerably below the current EUCAST ECOFF for E. faecium (ECOFF = 2 mg/L). Salinomycin and lasalocid ECOFFs were 1 and 2 mg/L, respectively. Strains carrying the previously identified narAB resistance genes clearly manifested a separate MIC distribution for narasin and salinomycin, but not for lasalocid, although a clear bias to the higher MIC values within the normal distribution could be observed. Monensin apparently displayed a broader MIC range (0.5-64 mg/L) with multiple modes, which precluded the establishment of an ECOFF for monensin.</p><p><strong>Conclusions: </strong>The study yielded novel ECOFFs for distinguishing WT E. faecium strains for the key veterinary ionophores, providing a mainstay for a better understanding of ionophore resistance in enterococci.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2361-2368"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12404726/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144753380","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":"Impact of empiric anti-VRE therapy on survival in vancomycin-resistant enterococcal bloodstream infection.","authors":"Tao-Hung Ou, Jia-Ling Yang, Chi-Ying Lin, Sung-Hsi Huang, Yu-Chung Chuang, Jann-Tay Wang, Yee-Chun Chen, Shan-Chwen Chang","doi":"10.1093/jac/dkaf225","DOIUrl":"10.1093/jac/dkaf225","url":null,"abstract":"<p><strong>Objectives: </strong>The aim of this study is to evaluate the benefit of early appropriate antibiotics in vancomycin-resistant Enterococcus (VRE) bloodstream infections (BSIs) amid increasing incidence and limited evidence supporting empirical VRE-active therapy.</p><p><strong>Methods: </strong>We performed a cohort study (2010-23) involving patients with VRE BSI who received empiric Gram-positive coverage. Patients who did not receive VRE-active therapy (daptomycin or linezolid) were excluded. Based on their initial regimen, patients were classified into an empiric anti-VRE group or a glycopeptide (vancomycin or teicoplanin) group. The primary outcome was 28-day mortality.</p><p><strong>Results: </strong>We included 134 patients: 46 in the empiric anti-VRE group and 88 in the glycopeptide group. The 28-day mortality rate was 53.7%. All glycopeptide recipients switched to daptomycin, and 29 of the 46 (63%) patients in the empiric anti-VRE group also received daptomycin. Time to VRE-active therapy was shorter in the empiric anti-VRE group (0 versus 2 days; P < 0.001), and each day's delay correlated with higher mortality (0 day: 37.0%, 1 day: 57.7%, ≥2 days: 64.5%; P = 0.02). The empiric anti-VRE group had a lower 28-day mortality rate (37.0% versus 62.5%, P = 0.006). Multivariable analysis adjusting for comorbidities, steroid use, infection focus and bacteraemia severity indicated that empiric anti-VRE therapy was independently associated with lower mortality (adjusted OR 0.41; 95% CI, 0.17-0.98; P = 0.046).</p><p><strong>Conclusions: </strong>Among patients with VRE BSI requiring empiric Gram-positive coverage, anti-VRE therapy was associated with reduced 28-day mortality compared with glycopeptides, even both groups eventually received VRE-active antibiotics. This highlights the critical role of timely, appropriate antibiotic to improve VRE BSI outcomes.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2408-2416"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144659242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Outcomes of ceftriaxone 2 g versus 1 g daily in hospitalized patients with pneumonia: a nationwide retrospective cohort study-authors' response.","authors":"Jumpei Taniguchi, Shotaro Aso, Hideo Yasunaga","doi":"10.1093/jac/dkaf257","DOIUrl":"10.1093/jac/dkaf257","url":null,"abstract":"","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2563-2564"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144674877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial use for the treatment of bacterial sexually transmitted infections among doxycycline post-exposure prophylaxis (DoxyPEP) users in Milan, Italy.","authors":"Angelo Roberto Raccagni, Sara Diotallevi, Riccardo Lolatto, Elena Bruzzesi, Flavia Badalucco Ciotta, Giacomo Ponta, Flavia Passini, Caterina Candela, Camilla Muccini, Antonella Castagna, Silvia Nozza","doi":"10.1093/jac/dkaf244","DOIUrl":"10.1093/jac/dkaf244","url":null,"abstract":"<p><strong>Background: </strong>Doxycycline post-exposure prophylaxis (DoxyPEP) is effective in reducing bacterial sexually transmitted infections (bSTIs) among MSM.</p><p><strong>Objectives: </strong>The aim of this study is to evaluate whether DoxyPEP introduction is associated with subsequent reduction of antimicrobial use among MSM.</p><p><strong>Methods: </strong>This is a retrospective study of MSM at the San Raffaele Hospital, Italy, who received DoxyPEP prescription from August 2022 to July 2024. DoxyPEP was suggested for intensive sexual activity (>5 partners). Adjusted %changes in incidence rate of bSTIs before and after DoxyPEP prescription were estimated using a pre-post within-person analysis by Poisson mixed-effects model. Use of DoxyPEP and ceftriaxone, benzylpenicillin and doxycycline for bSTI treatment was quantified as days of therapy (DOTs) per 1000 person-days (1000-PD). The observed DOTs after DoxyPEP prescription were increased with %changes derived from regressions to obtain the expected DOTs in absence of DoxyPEP.</p><p><strong>Results: </strong>Overall, 754 MSM were prescribed DoxyPEP; during follow-up, 222 (29.4%) reported using DoxyPEP. Median follow-up among DoxyPEP users were 15.8 months (IQR = 12.1-19.2) and 10.8 (6.88-13.1) before and after prescription, respectively. Among DoxyPEP users, 401 bSTIs (Tp 70, Ct 139, Ng 192) were detected before prescription and 146 (Tp 26, Ct 32, Ng 88) after. DOT per 1000-PD was 1.26 for ceftriaxone, 0.37 for penicillin and 3.21 for doxycycline after prescription; DoxyPEP DOT per 1000-PD was 7.00. Expected DOT in the absence of DoxyPEP was 4.85 (95% CI = 3.82-6.41) for ceftriaxone, 1.86 (95% CI = 1.17-2.87) for penicillin and 24.71 (95% CI = 17.18-37.36) for doxycycline.</p><p><strong>Conclusions: </strong>A significant reduction in antibiotics used for the treatment of bSTIs was achieved among DoxyPEP users.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2484-2486"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144707558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A multicentre study for determination of epidemiological cut-off values for Candida auris with EUCAST broth microdilution reference methodology.","authors":"Joseph Meletiadis, Jesus Guinea, Sevtap Arikan-Akdagli, Eelco F J Meijer, Jacques F Meis, Maiken Cavling Arendrup","doi":"10.1093/jac/dkaf241","DOIUrl":"10.1093/jac/dkaf241","url":null,"abstract":"<p><strong>Background: </strong>As EUCAST epidemiological cut-off values (ECOFFs) are not yet established for Candida auris, a multicentre study was conducted to determined (ECOFF) of echinocandins, amphotericin B and flucytosine using a global collection of C. auris isolates.</p><p><strong>Methods: </strong>MIC testing was performed in five centres according to the E.Def 7.4 reference methodology for anidulafungin, micafungin, amphotericin B and flucytosine using standard medium, and for rezafungin using standard medium supplemented with 0.002% Tween 20 as per protocol. A geographically diverse collection of 30 clinical C. auris strains with distinct short tandem repeat genotypes belonging to five different clades was tested. MIC distributions were constructed, and ECOFFs were determined on the basis of qualifying distributions according to EUCAST SOP 10.2 and using the ECOFFinder software, derivatization method and visual inspection.</p><p><strong>Results: </strong>The centre-specific modal MICs were: 0.008-0.03 mg/L for rezafungin, 0.016-0.06 mg/L for anidulafungin, 0.03-0.06 mg/L for micafungin, 0.5-1 mg/L for amphotericin B and 0.125-0.25 mg/L for flucytosine, and all complied with the EUCAST criterion of being within ±1 2-fold dilution from the most common modal MIC. Consensus EUCAST ECOFFs of 0.125 mg/L for rezafungin, 0.25 mg/L for anidulafungin and micafungin, 0.5 mg/L for flucytosine and 2 mg/L for amphotericin B were established.</p><p><strong>Conclusions: </strong>EUCAST ECOFFs have been determined for rezafungin, anidulafungin, micafungin, amphotericin B and flucytosine. They can be adopted to identify non-wild-type isolates and assist clinical breakpoint setting in the future when clinical outcome-MIC data are available.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2459-2465"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144731094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly drug-resistant Vibrio cholerae harbouring blaPER-7 isolated from travellers returning to England.","authors":"Satheesh Nair, Clare R Barker, Vineet Patel, Ching-Ying Poh, David R Greig, Israel Olonade, Paolo Ribeca, Claire Jenkins","doi":"10.1093/jac/dkaf232","DOIUrl":"10.1093/jac/dkaf232","url":null,"abstract":"<p><strong>Objectives: </strong>The current, seventh cholera pandemic (7PET) is notably different from the previous six, owing to its rapid global spread and increased transmission of antimicrobial resistance. The global emergence of MDR Vibrio cholerae is a public health concern. We aimed to interrogate WGS data from V. cholerae isolates referred to the UK Health Security Agency (formerly Public Health England, PHE) for the presence of blaPER-7 encoding resistance to the extended-spectrum cephalosporins.</p><p><strong>Methods: </strong>We reviewed 161 genomes of V. cholerae isolated between 2019 and 2024 from travellers returning to the UK, screening this dataset for resistance to the extended-spectrum cephalosporins encoded by blaPER-7.</p><p><strong>Results: </strong>We identified 3/51 V. cholerae O1 ST69 isolates and 1/110 non-O1 isolate belonging to ST555, harbouring blaPER-7 alongside mph(A), encoding azithromycin resistance. Long-read sequencing confirmed that both these genes were on a YemVchMDR1 element, that also possessed an MDR island carrying genes encoding resistance to aminoglycosides, sulphonamides and florfenicol. This element was located on an IncC plasmid in the ST69 O1 isolates but had inserted into the chromosome of the non-O1 isolate.</p><p><strong>Conclusions: </strong>Public health institutions have the ability and responsibility to monitor the burden and spread of highly drug-resistant V. cholerae via passive surveillance, informing clinical guidance, empirical treatment and travel advice.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2428-2432"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12404714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144649514","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":"Efficacy and safety of earlier switching to an oral antibiotic therapy for the treatment of Gram-positive bloodstream infections: a systematic review and meta-analysis.","authors":"ZhaoYi Tan, WenXin Liang, Na Zhang, BeiBei Liang, Nan Bai, Yun Cai","doi":"10.1093/jac/dkaf209","DOIUrl":"10.1093/jac/dkaf209","url":null,"abstract":"<p><strong>Background: </strong>Infection specialists show considerable variation in practice, with some advocating IV-to-oral switch for Gram-positive bloodstream infections (GP-BSIs). The efficacy and safety of early switching remain unclear.</p><p><strong>Methods: </strong>Systematic review of the efficacy of an early switch to oral antimicrobial therapy in patients with GP-BSIs compared with IV therapy, including treatment failure, all-cause mortality, recurrence, hospital readmission rates, length of hospital stay and adverse events (AEs). PubMed, Embase and the Cochrane Library Database were independently searched up to May 2025. ROBINS-I and ROB-2 tools were used.</p><p><strong>Results: </strong>A total of 27 studies with 6015 patients were included. Although treatment failure in the IV-to-oral group is comparable to that of IV treatment, the 30-day (OR 0.33, 95% CI 0.13, 0.83) and 90-day all-cause mortality (OR 0.59, 95% CI 0.36, 0.97) in patients with GP-BSIs were significantly lower in association with oral switch. Notably, the decline in all-cause mortality rate was more pronounced in the subgroups of S. aureus (OR 0.37, 95% CI 0.26, 0.53), oral conversion time ≥7 days (OR 0.25, 95% CI 0.16, 0.38) and switched to oral non-β-lactam antibiotics (OR 0.58, 95% CI 0.39, 0.86). Moreover, oral switch therapy significantly reduced hospital stay (MD -6.21 days, 95% CI -7.99, -4.43). Recurrence rate, hospital readmission rates and AEs were similar between IV and oral switch groups.</p><p><strong>Conclusions: </strong>This meta-analysis, although primarily based on observational studies, supports that transitioning from IV to oral therapy constitutes a suitable alternative for patients with GP-BSIs exclusively managed via parenteral administration.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2344-2360"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Paradoxical interaction between dalbavancin and β-lactams against endocarditis-associated Enterococcus faecalis clinical isolates.","authors":"David Luque Paz, Adrien Turban, François Guérin, Malo Penven, Matthieu Revest, Cristina García-de-la-Mària, José M Miró, Pierre Tattevin, Vincent Cattoir","doi":"10.1093/jac/dkaf262","DOIUrl":"10.1093/jac/dkaf262","url":null,"abstract":"<p><strong>Background: </strong>There are limited in vitro synergistic studies on dalbavancin against enterococci. We aimed to assess the in vitro activity of dalbavancin against Enterococcus faecalis strains, and to explore the interaction between dalbavancin and β-lactams.</p><p><strong>Methods: </strong>MIC and MBC values were determined against a panel of 10 clinical isolates and two reference strains of E. faecalis. Checkerboard assays were conducted for the initial screening for additive, synergistic or antagonistic effect between dalbavancin and different classes of antibiotics. Thereafter, time-kill (TK) assays with β-lactams were performed to confirm the results.</p><p><strong>Results: </strong>All strains were tolerant to dalbavancin (MBC/MIC ratios >32). For 11 of the 12 strains tested, a synergy was found in TK assays between dalbavancin (0.5 × MIC) and each β-lactam (0.25 × MIC), namely amoxicillin, cefazolin, ceftriaxone, cefepime, ceftobiprole, ertapenem and meropenem. Paradoxically, we systematically found reduced efficacy of β-lactams in combination with dalbavancin at concentrations greater than or equal to MIC. At these concentrations, TK assays demonstrated that a combination with dalbavancin resulted in an antagonism of amoxicillin (8/12 strains), ceftobiprole (10/12 strains) and ertapenem (5/12 strains) activities. Dalbavancin alone at 32 mg/L or in combination with amoxicillin at 2 mg/L induced a slow bacterial reduction (median decrease of 0.4 log10 at 24 h for both regimens), whereas amoxicillin alone at 2 mg/L reduced the E. faecalis inoculum by 3.2 log10 (IQR, 3.1-3.4).</p><p><strong>Conclusions: </strong>Dalbavancin exhibits poor activity against E. faecalis, and impairs the activity of β-lactams, especially amoxicillin. Dalbavancin should be used with caution in the treatment of E. faecalis infective endocarditis.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2524-2529"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144731097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overcoming antimicrobial resistance in Helicobacter pylori: the roles of collateral sensitivity and biofilm dynamics.","authors":"Siddharth Singh, Sonali Adhikari, Nidhi Varshney, Chanchal Rani, Awanish Kumar, Rajesh Kumar, Hem Chandra Jha","doi":"10.1093/jac/dkaf233","DOIUrl":"10.1093/jac/dkaf233","url":null,"abstract":"<p><strong>Objectives: </strong>The increasing prevalence of antimicrobial resistance (AMR) in Helicobacter pylori (H. pylori) poses a significant challenge to eradication strategies. This study investigates the role of biofilm formation in AMR and explores the potential of collateral sensitivity (CS) as a therapeutic approach to optimize treatment regimens.</p><p><strong>Methods: </strong>Two H. pylori clinical isolates (HJ1 and HJ9) were assessed for antibiotic susceptibility using broth microdilution assays. Biofilm formation was characterized through crystal violet staining, scanning electron microscopy and Raman microspectroscopy. CS profiling was conducted by generating adaptive-resistant strains through serial exposure to sub-inhibitory antibiotic concentrations, and susceptibility testing using disk diffusion assays.</p><p><strong>Results: </strong>• The antibiotic-resistant strain HJ1 exhibited enhanced biofilm formation over time compared to HJ9, with Raman microspectroscopy revealing significant biochemical alterations in its extracellular polymeric substance (EPS).• CS profiling demonstrated reciprocal susceptibility changes; resistance to tetracycline increased levofloxacin susceptibility in HJ1, while resistance to rifampicin increased amoxicillin susceptibility in HJ9.• The findings suggest that strategic antibiotic cycling, leveraging CS relationships, may enhance treatment efficacy and limit resistance development.</p><p><strong>Conclusions: </strong>Biofilm formation plays a critical role in H. pylori AMR, reinforcing the challenge of eradication. CS profiling indicates that resistance acquisition can be exploited therapeutically to enhance antibiotic efficacy. Integrating CS-based treatment strategies with biofilm-disrupting interventions may provide a novel approach of overcoming multi-drug resistance in H. pylori. Further research is required to elucidate the molecular mechanisms underpinning CS and biofilm-mediated resistance to refine treatment strategies.</p>","PeriodicalId":14969,"journal":{"name":"Journal of Antimicrobial Chemotherapy","volume":" ","pages":"2433-2441"},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}