International Journal of Antimicrobial Agents最新文献

{"title":"EnvZ mutation–driven downregulation of catecholate siderophore receptors and concurrent TonB complex repression confer cefiderocol resistance in a KPC-producing ST11-KL64 hypervirulent Klebsiella pneumoniae","authors":"Danni Pu ,&nbsp;Xianxia Zhuo ,&nbsp;Rongrong Song ,&nbsp;Chunhui Wang ,&nbsp;Jiankang Zhao ,&nbsp;Bin Cao","doi":"10.1016/j.ijantimicag.2025.107693","DOIUrl":"10.1016/j.ijantimicag.2025.107693","url":null,"abstract":"<div><h3>Objectives</h3><div>Cefiderocol is an ultimate antibiotic option for Carbapenem-resistant hypervirulent <em>Klebsiella pneumoniae</em> (CR-hvKP). While resistance often involves metallo-β-lactamases, mechanisms in KPC-producing strains are unclear. This study aimed to elucidate novel cefiderocol resistance mechanisms in a clinical KPC-producing ST11-KL64 CR-hvKP isolate.</div></div><div><h3>Methods</h3><div>Cefiderocol-resistant mutants were generated through <em>in vitro</em> experimental evolution. Resistance-associated mutations were identified by whole-genome sequencing. Transcriptomic and proteomic analyses were performed to characterize global regulatory changes and were validated by qRT-PCR and targeted genetic manipulation. Additional tests examined siderophore production, intracellular iron levels, bacterial fitness, oxidative stress tolerance, and macrophage survival.</div></div><div><h3>Results</h3><div>All high-level cefiderocol-resistant mutants acquired a gain-of-function mutation in the sensor kinase EnvZ (V145G). Integrated transcriptomic and proteomic analyses showed that the <em>envZ</em> mutation drove marked downregulation of catecholate siderophore receptors (<em>cirA</em> and <em>fepA</em>), impairing cefiderocol uptake. In parallel, the TonB–ExbB–ExbD energy transduction complex was independently and stably downregulated, synergistically contributing to resistance. Notably, <em>envZ</em> mutation–associated repression of the enterobactin biosynthesis gene <em>entB</em> paradoxically increased cefiderocol susceptibility, indicating a regulatory trade-off. Resistant mutants exhibited reduced siderophore production, impaired intracellular iron accumulation, and significant fitness costs, including attenuated growth, reduced oxidative stress tolerance, and decreased survival within macrophages.</div></div><div><h3>Conclusions</h3><div>In conclusion, this work uncovers a novel cefiderocol resistance mechanism in KPC-producing ST11-KL64 CR-hvKp, initiated by the <em>envZ</em> mutation, which causes the downregulation of catecholate siderophore receptors. This receptor repression, combined with the stable downregulation of the TonB-ExbB-ExbD energy complex, severely impairs cefiderocol's “Trojan horse” active uptake. This resistance mechanism is accompanied by a fitness trade-off, providing critical insights into the evolution of these superbugs.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107693"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145800434","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":"Formation of a novel multiresistance plasmid co-carrying tigecycline, carbapenem, and other resistance genes by recombination during conjugative transfer in Klebsiella pneumoniae","authors":"Runhao Yu ,&nbsp;Zhong Chen ,&nbsp;Stefan Schwarz ,&nbsp;Hong Yao ,&nbsp;Chenglong Li ,&nbsp;Xiang-Dang Du","doi":"10.1016/j.ijantimicag.2025.107683","DOIUrl":"10.1016/j.ijantimicag.2025.107683","url":null,"abstract":"<div><h3>Objective</h3><div><em>Klebsiella pneumoniae</em> is a major global nosocomial pathogen, and strains acquiring extended-spectrum β-lactamase (ESBL) or carbapenemase resistance genes exhibit extensive clinical drug resistance, posing a serious public health threat. This study aimed to characterize the genetic features and transferability of resistance determinants in a clinically isolated multidrug-resistant <em>K. pneumoniae</em> strain.</div></div><div><h3>Methods</h3><div>A multidrug-resistant <em>K. pneumoniae</em> strain was isolated from clinical samples. Whole-genome sequencing was performed to identify the resistance genes carried by the strain and the transposase sequences within the genetic environment of the target resistance genes. Conjugative transfer experiments were conducted to verify the transferability of the identified resistance genes and their genetic recombination characteristics.</div></div><div><h3>Results</h3><div>The clinical isolate was confirmed to co-carry a <em>tet</em>(A) variant, <em>tmexCD2-toprJ2</em>, and <em>bla</em>_NDM-1 resistance genes. Whole-genome sequencing revealed the presence of IS<em>26</em>, IS<em>3000</em>, and ∆<em>tnpA</em> transposase sequences in the genetic environment of <em>tet</em>(A)v and <em>bla</em>_NDM-1 genes. Conjugative transfer experiments verified the transferability of the different resistance genes, and notably, recombination and co-transfer events of <em>tet</em>(A)v and <em>bla</em>_NDM-1 genes were detected within the conjugative plasmid of the strain.</div></div><div><h3>Conclusions</h3><div>Transposases play a crucial role in the formation of complex multidrug-resistant <em>K. pneumoniae</em> strains. The findings of this study provide a novel perspective and critical evidence for elucidating the antimicrobial resistance mechanisms and dissemination pathways of multidrug-resistant <em>K. pneumoniae</em>.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107683"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145654199","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":"ATP-binding cassette transporters mediate and regulate metronidazole resistance in Clostridioides difficile","authors":"Teng Xu ,&nbsp;Ying Zhou ,&nbsp;Qingqing Xu ,&nbsp;Li Wang ,&nbsp;Yu Zhou ,&nbsp;Shi Wu ,&nbsp;Haihui Huang","doi":"10.1016/j.ijantimicag.2025.107709","DOIUrl":"10.1016/j.ijantimicag.2025.107709","url":null,"abstract":"<div><h3>Objective</h3><div>Metronidazole (MTZ) resistance in <em>Clostridioides difficile</em> is associated with decreased efficacy of MTZ. We studied the MTZ-resistant <em>C. difficile</em> strain sh182IR (minimum inhibitory concentration [MIC] = 32 mg/L) to characterize the role of ATP-binding cassette (ABC) family transporters in MTZ resistance in <em>C. difficile</em>. The strain overexpresses ABC multidrug efflux pump components.</div></div><div><h3>Methods</h3><div>In strain sh182IR, ClosTron mutagenesis was applied to disrupt <em>cd17530</em>, a gene encoding the ABC transporter ATP-binding protein, and the effects on efflux capacity and MIC of MTZ were evaluated. The upstream regulatory gene <em>cd17520</em> was also sequenced.</div></div><div><h3>Results</h3><div>Disruption of <em>cd17530</em> reduced the efflux capacity of fluorescent substrates and MIC of MTZ in <em>C. difficile</em> sh182IR. Repair of <em>cd17530</em> successfully restored the MTZ MIC and efflux capacity of the strain. We also confirmed that the upstream TetR/AcrR family transcription factor gene <em>cd17520</em> in sh182IR harbours a frameshift mutation. This mutation resulted in the loss of function of the peptide chain encoded by the gene and upregulation of cd17530-17540-17550.</div></div><div><h3>Conclusions</h3><div>The frameshift mutation in the transcriptional repressor <em>cd17520</em>, which results in the derepression of the cd17530-17540-17550 operon, contributes to ABC transporter-mediated MTZ resistance in <em>C. difficile</em>.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107709"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145905677","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":"Antibiotic class comparisons for the treatment of pyelonephritis and complicated urinary tract infections: A systematic review and meta-analysis","authors":"Digbijay Kunwar ,&nbsp;Itay Zahavi ,&nbsp;Judit Olchowski ,&nbsp;Hagar Dallasheh ,&nbsp;Mical Paul","doi":"10.1016/j.ijantimicag.2025.107696","DOIUrl":"10.1016/j.ijantimicag.2025.107696","url":null,"abstract":"<div><h3>Background</h3><div>The relative efficacy of antibiotic classes for pyelonephritis and complicated UTI (cUTI) remains unclear, as different antibiotic classes vary in antimicrobial activity, pharmacodynamics and pharmacokinetics.</div></div><div><h3>Methods</h3><div>Systematic review and meta-analysis. We searched PubMed, Cochrane CENTRAL, clinical-trial registries and conference abstracts through 30 November 2025. Randomised controlled trials comparing antibiotic classes in adults with pyelonephritis/complicated UTI (cUTI) were eligible (PROSPERO CRD42023448020). Five comparisons were analysed: quinolones vs β-lactams, cephalosporins vs penicillins, aminoglycosides vs quinolones or beta-lactams, trimethoprim-sulfamethoxazole vs quinolones or beta-lactams and ESBL-active agents vs non-ESBL-active antibiotics. The primary outcome was clinical cure by day 7. We compiled risk ratios (RRs) with 95% confidence intervals (CI) using fixed-effect meta-analyses. Risk of bias was assessed with ROB 2.0 and evidence certainty using GRADE.</div></div><div><h3>Results</h3><div>Thirty-seven RCTs were included, comprising 7,904 mainly hospitalized participants (62.7% women). Most had some risk-of-bias concerns. No significant difference in clinical cure was observed with moderate evidence certainty, across all comparisons. Relapse increased significantly with TMP/SMX compared to quinolones or beta-lactams (RR 2.34 [1.29, 4.24]) and microbiological cure improved with ESBL-active antibiotics (RR 1.07 [1.02, 1.13], very low certainty evidence). TMP/SMX increased adverse events and aminoglycosides increased nephrotoxicity and resistance acquisition.</div></div><div><h3>Conclusions</h3><div>Clinical cure was comparable across all comparisons. This supports basing antibiotic selection on local resistance patterns, patient factors and toxicity profiles rather than presumed class superiority.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107696"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145827746","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":"Regorafenib, a multitargeted kinase inhibitor, inhibits enterovirus 71 infection by suppressing the MAPK pathway","authors":"Xinyu Zhang ,&nbsp;Yuanyuan Cao ,&nbsp;Yu Liu ,&nbsp;Shengqun Deng ,&nbsp;Shilong Lv ,&nbsp;Wangping Peng ,&nbsp;Lu Fang ,&nbsp;Luyao Zhang ,&nbsp;Yaling Wu ,&nbsp;Li Yu ,&nbsp;Baojing Lu ,&nbsp;Shenghai Huang ,&nbsp;Qi Tang","doi":"10.1016/j.ijantimicag.2025.107711","DOIUrl":"10.1016/j.ijantimicag.2025.107711","url":null,"abstract":"<div><h3>Objectives</h3><div>To investigate the <em>in vitro</em> and <em>in vivo</em> antiviral efficacy and underlying mechanism of regorafenib against Enterovirus 71 (EV71), as no licensed direct-acting antivirals are available for severe cases.</div></div><div><h3>Methods</h3><div>The inhibitory effect of regorafenib against EV71 was evaluated using qRT‒PCR, Western blot, IF, and CPE assays. The stage of the viral life cycle targeted by regorafenib was determined via time-of-addition, binding and entry assays. <em>In vivo</em> efficacy was assessed in an EV71-infected murine model by monitoring body weight, clinical scores, and viral RNA loads in tissues. The mechanism of action was elucidated by analyzing the effect of regorafenib on the MEK/ERK phosphorylation in the host mitogen-activated protein kinase (MAPK) pathway. A potential interaction with the EV71 capsid protein VP1 was investigated using molecular docking.</div></div><div><h3>Results</h3><div>Regorafenib demonstrated potent, dose-dependent antiviral activity against EV71 <em>in vitro</em> and exhibited broad-spectrum efficacy against multiple human enteroviruses. In an EV71-infected murine model, oral administration of regorafenib at doses of 1.25 or 2.5 mg/kg/day significantly alleviated infection-associated symptoms and reduced viral loads in key organs. Mechanistic investigations revealed that regorafenib suppressed viral replication by inhibiting the phosphorylation of MEK and ERK in the MAPK pathway. Molecular docking studies further predicted that regorafenib binds to the viral capsid protein VP1, providing a potential structural basis for its antiviral effect.</div></div><div><h3>Conclusions</h3><div>Our findings establish that regorafenib exhibits inhibitory activity against EV71 <em>in vitro</em> and <em>in vivo</em>, which warrants further preclinical evaluation as a candidate lead compound.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107711"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145905623","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":"Superintegron of Vibrio paracholerae as a reservoir of antibiotic resistance genes","authors":"Sergio Mascarenhas Morgado,&nbsp;Erica Lourenço da Fonseca,&nbsp;Ana Carolina Paulo Vicente","doi":"10.1016/j.ijantimicag.2025.107708","DOIUrl":"10.1016/j.ijantimicag.2025.107708","url":null,"abstract":"","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107708"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145889237","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":"Development of ceftazidime–avibactam resistance driven by conversion of blaKPC-2 to blaKPC-78 during treatment of ST463 carbapenem-resistant Pseudomonas aeruginosa infection","authors":"Haotian Xu ,&nbsp;Tingjuan Zhang ,&nbsp;Xueying Cui ,&nbsp;Jingyi Guo ,&nbsp;Pengpeng Min ,&nbsp;Chengjin Wu ,&nbsp;Xinyan Tang ,&nbsp;Longjie Zhou ,&nbsp;Linfang Wang ,&nbsp;Xi Li","doi":"10.1016/j.ijantimicag.2025.107703","DOIUrl":"10.1016/j.ijantimicag.2025.107703","url":null,"abstract":"<div><h3>Objective</h3><div>The emergence of ceftazidime-avibactam (CZA)-resistant carbapenem-resistant <em>Pseudomonas aeruginosa</em> (CRPA) poses a major clinical challenge in contemporary clinical practice. In this study, we report the first identification of <em>bla</em>_KPC-78, which is driven by a mutation from <em>bla</em>_KPC-2 in a clinical CRPA strain.</div></div><div><h3>Methods</h3><div>Six <em>bla</em>_KPC-78 CRPA isolates, along with two <em>bla</em>_KPC-2 strains from one patient, were subjected to antimicrobial susceptibility testing (AST), whole-genome sequencing (WGS), conjugation, and growth assays. Mechanistic investigations included structural modelling and docking, cloning experiments, efflux inhibition, and reverse transcription quantitative polymerase chain reaction (RT-qPCR).</div></div><div><h3>Results</h3><div>The emergence of CZA resistance in CRPA isolates was driven by a mutation from <em>bla</em>_KPC-2 to <em>bla</em>_KPC-78 during CZA therapy. The AST results showed that all KPC-78-producing CRPA exhibited a multidrug-resistant phenotype. WGS revealed that these strains belong to ST463, and <em>bla</em>_KPC-78 gene was located in a type I plasmid and carried by the Tn<em>6296</em> transposon. Additionally, the co-occurrence of efflux pump overexpression and KPC-78 enzyme's stronger binding affinities for both ceftazidime and avibactam contributed to high-level resistance to CZA in CRPA. Moreover, despite the slower logarithmic growth of KPC-78-producing <em>P. aeruginosa</em> in monoculture, <em>in vitro</em> competitive co-culture experiments revealed that it conferred a competitive advantage over the KPC-2-producing strains.</div></div><div><h3>Conclusions</h3><div>We report the first identification of <em>bla</em>_KPC-78 in CRPA, delineate its evolutionary trajectory, and describe its genetic characteristics. The elevated hydrolytic activity of the KPC-78 producing strain, along with the overexpression of efflux pumps, contributes to its high-level resistance to CZA. Considering the widespread occurrence of ST463 CRPA in China, it is imperative to enhance the surveillance of KPC-producing CRPA.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107703"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145850089","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":"In reply to the letter to editor regarding “Comparison of ceftazidime-avibactam with other appropriate antimicrobial therapy for the treatment of OXA-48- or KPC-producing Enterobacterales infections in Turkiye: A multi-centre retrospective matched-cohort study”","authors":"Abdullah T. Aslan ,&nbsp;Patrick N.A. Harris ,&nbsp;David L. Paterson","doi":"10.1016/j.ijantimicag.2025.107691","DOIUrl":"10.1016/j.ijantimicag.2025.107691","url":null,"abstract":"","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107691"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145742497","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":"Aztreonam–avibactam pharmacokinetics during extracorporeal membrane oxygenation support: First insights from a case report","authors":"Alba Pau-Parra ,&nbsp;Sònia Luque ,&nbsp;Laura Doménech ,&nbsp;María Martínez-Pla ,&nbsp;Xavier Nuvials ,&nbsp;Manuel Sosa Garay ,&nbsp;Ibai Los-Arcos ,&nbsp;Aldair Conto ,&nbsp;Fernando Lasteros ,&nbsp;Elisabet Gallart ,&nbsp;Maria Queralt Gorgas Torner ,&nbsp;Ricard Ferrer ,&nbsp;Jordi Riera","doi":"10.1016/j.ijantimicag.2025.107692","DOIUrl":"10.1016/j.ijantimicag.2025.107692","url":null,"abstract":"","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107692"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145742533","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":"Enhanced molecular surveillance for gonococcal resistance during doxycycline post-exposure prophylaxis implementation","authors":"Ziyuan Zhao ,&nbsp;Leshan Xiu ,&nbsp;Junping Peng","doi":"10.1016/j.ijantimicag.2025.107689","DOIUrl":"10.1016/j.ijantimicag.2025.107689","url":null,"abstract":"<div><h3>Objective</h3><div>The introduction of doxycycline post-exposure prophylaxis (doxy-PEP) as a strategy to reduce the risk of bacterial sexually transmitted infections has raised concerns about the potential for rapid selection of tetracycline resistance and the emergence of ceftriaxone-resistant strains. This study aimed to develop a molecular surveillance method to monitor antimicrobial resistance (AMR) in <em>Neisseria gonorrhoeae</em> (NG) during doxy-PEP implementation.</div></div><div><h3>Methods</h3><div>We developed a high-resolution melting (HRM) analysis-based molecular assay, termed HRM-doxyPEP, to enhance surveillance of NG AMR. Validation was conducted with strains of known susceptibility profiles, and further evaluation was performed on clinical samples, comparing HRM results with quantitative PCR, whole-genome sequencing, and PCR-sequencing.</div></div><div><h3>Results</h3><div>The HRM-doxyPEP assay demonstrated high analytical specificity and a detection limit of 20 copies/reaction, enabling the detection of low levels of target DNA in clinical samples. Validation with strains of known susceptibility profiles showed 84% consistency with antimicrobial susceptibility testing results. Clinical sample testing revealed 100% sensitivity and specificity for identifying NG infection, tracking ceftriaxone-resistant FC428-like strains, and detecting <em>tetM</em> associated with tetracycline resistance.</div></div><div><h3>Conclusions</h3><div>The HRM-doxyPEP assay offers an accurate, affordable, and scalable tool for enhanced molecular surveillance of AMR in NG during doxy-PEP implementation.</div></div>","PeriodicalId":13818,"journal":{"name":"International Journal of Antimicrobial Agents","volume":"67 2","pages":"Article 107689"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145742543","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}