JAC-Antimicrobial Resistance最新文献

{"title":"Do policies that allow access to unregistered antimicrobials address the unmet need? Australia as a case study of a high-income country with universal healthcare.","authors":"Nadine T Hillock, Allen Cheng, Andrew Bowskill","doi":"10.1093/jacamr/dlae216","DOIUrl":"https://doi.org/10.1093/jacamr/dlae216","url":null,"abstract":"<p><strong>Background: </strong>Ensuring timely and equitable access to effective and optimal antimicrobials is crucial for optimal patient care, to minimize the use of less appropriate treatment options and reduce the risk of antimicrobial resistance (AMR).</p><p><strong>Objectives: </strong>To determine the average time for new antibacterials to gain registration for use in Australia after obtaining marketing approval internationally, and to quantify the use of 'new' and older unregistered antimicrobials in Australian clinical practice between 2018 and 2023.</p><p><strong>Methods: </strong>Two data sources were utilized to estimate the usage of antimicrobials not registered for use in Australia. Annual hospital inpatient usage data were sourced from the National Antimicrobial Utilisation Surveillance Program (NAUSP) and data on Special Access Scheme (SAS) applications for unregistered antimicrobial was sourced from the Australian Government Department of Health and Aged Care.</p><p><strong>Results: </strong>Between 2018 and 2023 there were 36 131 applications to access unapproved antimicrobials in Australia. In 26.6% of cases, access to an unapproved antimicrobial was for the treatment of a critically ill patient. Levofloxacin, pyrazinamide, tetracycline and pristinamycin were the most frequently accessed unregistered antimicrobials. Applications for 'new' antibacterials increased from 55 in 2018 to 249 in 2023. Inpatient use of nine new antibacterials was reported in Australian hospitals in 2023, two registered and seven unregistered.</p><p><strong>Conclusions: </strong>Unapproved antimicrobials are frequently accessed by clinicians for patients unable to be treated with registered antimicrobials in Australia. Policy reform and economic incentives are required to support the registration of antimicrobials needed for otherwise untreatable infections and to ensure the sustainability of supply.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlae216"},"PeriodicalIF":3.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11878572/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143557083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Duration of antibiotic treatment for respiratory tract infections in primary care.","authors":"Carl Llor, Malene Plejdrup Hansen, Jesper Lykkegaard, Jonas Olsen, Bent Håkan Lindberg, Ingrid Keilegavlen Rebnord, Pia Touboul Lundgren, Pascale Bruno, Anna Kowalczyk, Christos Lionis, Ruta Radzeviciene, Lina Jaruseviciene, Lars Bjerrum, Ana García-Sangenís","doi":"10.1093/jacamr/dlaf028","DOIUrl":"10.1093/jacamr/dlaf028","url":null,"abstract":"<p><strong>Objectives: </strong>The primary driver of antimicrobial resistance is excessive antibiotic use, posing a global threat to public health. Reducing individual exposure to antibiotics is a key to addressing the problem. This study aimed to assess the duration of antibiotic courses administered to patients with acute respiratory tract infections (RTIs) in primary care.</p><p><strong>Methods: </strong>Consecutive patients presenting with RTI symptoms were prospectively included from general practices and out-of-hours services in France, Greece, Lithuania, Poland and Spain for two winter periods (February to April 2022 and 2023). Data were collected using a paper-based Audit Project Odense template, with clinicians recording patient age, gender, RTI diagnosis, type of antibiotic prescribed and treatment duration.</p><p><strong>Results: </strong>A total of 196 doctors (133 in general practice and 63 in out-of-hours services) registered 11 270 cases, with 34.0% (3835) receiving antibiotics. The mean antibiotic course duration was 7.52 days (SD 2.11), which was significantly longer for pneumonia, COVID-19 infection and pharyngotonsillitis (8.01, 8.00 and 7.74 days, respectively), and lowest for predominantly viral infections, such as the common cold and flu infection, laryngitis and acute bronchitis (6.32, 6.48 and 6.98 days, respectively; <i>P</i> < 0.001). A total of 26.7% of the courses were prescribed for 10 days or longer.</p><p><strong>Conclusions: </strong>Antibiotic courses for common RTIs are often prolonged, which does not align with current recommendations for course duration. Antibiotics should be avoided in cases of predominantly viral infections and most mixed infections; however, if deemed necessary, the courses should be substantially reduced to minimize unnecessary exposure.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf028"},"PeriodicalIF":3.7,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11851008/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143501381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging β-lactam non-susceptibility in <i>Group A Streptococcus</i>: implications for Ethiopia's healthcare system.","authors":"Alene Geteneh, Sirak Biset, Melese Abate Reta","doi":"10.1093/jacamr/dlaf020","DOIUrl":"10.1093/jacamr/dlaf020","url":null,"abstract":"<p><p>The emergence of β-lactam non-susceptibility in <i>Group A Streptococcus</i> (GAS) or <i>Streptococcus pyogenes</i> represents a major challenge for the global public health, particularly in resource-limited settings like Ethiopia. GAS, a primary cause of pharyngitis and invasive infections, is conventionally treated with β-lactam antibiotics such as penicillin. However, the recent evidence raises concerns about the treatment efficacy with reduced susceptibility, the diagnostic limitations, and the potential for complications such as acute rheumatic fever. This commentary calls for attention to the antimicrobial resistance trends in Ethiopian GAS isolates, underscoring the need for routine susceptibility testing, advanced molecular diagnostics, and strengthened laboratory capacities to guide effective treatment strategies and mitigate the antibiotic resistance-associated risks.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf020"},"PeriodicalIF":3.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11844239/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143483095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heteroresistance associated with the production of fosfomycin-resistant inner colonies during disk diffusion testing among a geographically diverse collection of <i>Klebsiella pneumoniae</i> clinical isolates.","authors":"Morgan L Bixby, Lindsey B Collins, Ellora C Daley, Jenna M Salay, Sofia Oliver, Alexandra L Bryson, Elizabeth B Hirsch","doi":"10.1093/jacamr/dlaf013","DOIUrl":"10.1093/jacamr/dlaf013","url":null,"abstract":"<p><strong>Background: </strong>Fosfomycin susceptibility breakpoints apply only to <i>Escherichia coli</i> despite clinical use against <i>Klebsiella pneumoniae.</i> EUCAST and CLSI have different breakpoints and guidelines for disk diffusion (DD) interpretation that are frequently extrapolated to <i>K. pneumoniae.</i> Guidelines differ in interpreting inner colonies (IC) that grow within the zone of inhibition, but specificity to <i>E. coli</i> leaves knowledge gaps when extrapolating to other uropathogens.</p><p><strong>Objectives: </strong>To examine the frequency and MIC of <i>K. pneumoniae</i> IC during fosfomycin DD testing and to determine potential relationships between IC production, heteroresistance and <i>fosA</i> presence.</p><p><strong>Methods: </strong>A collection of <i>K. pneumoniae</i> clinical isolates (<i>n</i> = 262) and their IC (<i>n</i> = 116) underwent broth microdilution testing. Heteroresistance screening and PCR for <i>fosA</i> was performed on susceptible isolates that either never produced (NP) IC (<i>n</i> = 14) or produced ≥5 resistant IC (<i>n</i> = 43).</p><p><strong>Results: </strong>The MIC range (≤2 to >256 mg/L) of clinical isolates increased to 32 to >1024 mg/L for the IC collection with a median MIC increase of three, 2-fold dilutions. IC producers had 1.71 greater odds (<i>P</i> < 0.01) of a positive heteroresistance screen compared to NP isolates. No relationship was found between <i>fosA</i> presence and either IC production or heteroresistance.</p><p><strong>Conclusions: </strong>Production of ≥5 IC among clinical <i>K. pneumoniae</i> isolates was frequent and often resulted in an increased IC isolate MIC. Significantly greater odds of heteroresistance among IC producers were found when compared to NP isolates. Thus, presence of IC during fosfomycin DD testing should prompt avoidance of fosfomycin treatment.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf013"},"PeriodicalIF":3.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11840249/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143467867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AMRrounds: presumed mechanisms of resistance in a case of XDR <i>Klebsiella pneumoniae</i> empyema.","authors":"Michael Casias, Madison Salam","doi":"10.1093/jacamr/dlaf019","DOIUrl":"10.1093/jacamr/dlaf019","url":null,"abstract":"","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf019"},"PeriodicalIF":3.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11839836/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143467866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host-response testing with MeMed BV in community-acquired pneumonia: an economic evaluation from the UK NHS perspective.","authors":"Emily Gregg, Sara Graziadio, William Green, Daniela Afonso, Monica Garrett, Karina Watts, Deborah Watkins, Enitan D Carrol, Jonathan Cooke, Tim Felton","doi":"10.1093/jacamr/dlaf016","DOIUrl":"10.1093/jacamr/dlaf016","url":null,"abstract":"<p><strong>Background: </strong>Community-acquired pneumonia (CAP) remains a leading cause of hospital admissions and mortality. A novel host-response test, MeMed BV (MMBV), has been developed for discriminating between bacterial and viral infection that could improve the clinical management of CAP.</p><p><strong>Objectives: </strong>To evaluate the cost-effectiveness of using MMBV to guide antibiotic decisions in the clinical management of CAP in the UK.</p><p><strong>Methods: </strong>An economic model was developed to understand the incremental cost per person associated with the implementation of MMBV from the UK NHS perspective. A qualitative care pathway analysis was performed to inform the standard of care (SOC) and SOC plus MMBV (SOC + MMBV) clinical pathways captured in the model.</p><p><strong>Results: </strong>In the base case analysis, the SOC + MMBV strategy for a hypothetical cohort of 1000 patients (adults and children modelled independently) presenting to the emergency department with suspected CAP was estimated to provide total cost savings of £134 018 and £105 750 for adults and children, respectively. Cost savings were associated with reductions in total antibiotic treatment, the number of patients receiving additional diagnostic tests, and hospital admissions. Deterministic sensitivity analysis revealed that the specificity of SOC + MMBV and sensitivity of the SOC were primary drivers of the cost model for adults, whereas the specificity of SOC and SOC + MMBV were primary drivers for paediatrics.</p><p><strong>Conclusions: </strong>Overall, the model predicts that the introduction of SOC + MMBV has the potential to be cost-saving and promote antimicrobial stewardship for both adult and paediatric CAP patients.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf016"},"PeriodicalIF":3.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836884/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the impact of using a patient counselling prompt-the TARGET antibiotic checklist in England's community pharmacies.","authors":"Sejal Parekh, Lingqian Xu, Catherine V Hayes, Kieran Hand, Diane Ashiru-Oredope, Donna M Lecky","doi":"10.1093/jacamr/dlaf018","DOIUrl":"10.1093/jacamr/dlaf018","url":null,"abstract":"<p><strong>Background: </strong>An estimated 1.27 million deaths globally were caused by antibiotic-resistant infections in 2019. Outcome 2 of the UK national action plan to combat antimicrobial resistance is improved public engagement and education with a specific and measurable target.</p><p><strong>Objectives: </strong>To evaluate and compare 2 years of the use of the TARGET antibiotic checklist in England's community pharmacies via the Pharmacy Quality Scheme (PQS).</p><p><strong>Methods: </strong>The use of the TARGET antibiotic checklist was incentivized in the PQS for 2021-22 and 2023-24 for patients presenting with antibiotic prescription in community pharmacy during a 4 week period each year.</p><p><strong>Results: </strong>A total of 406 333 patients were counselled using the TARGET antibiotic checklist, with 10 081 community pharmacies participating in either year and 6209 community pharmacies participating in both years. The most common indications for both years were chest and urinary tract infections with amoxicillin and nitrofurantoin, respectively, being the most frequently prescribed antibiotics for both PQS years examined. A total of 27 898 influenza vaccinations were delivered by community pharmacies prompted by discussions whilst using the antibiotic checklist. In addition, 140 473 patient information leaflets were provided to patients to improve knowledge about their condition and treatment and to support future self-care.</p><p><strong>Discussion: </strong>The investment in training and resources for community pharmacies through the PQS has provided opportunities for strengthening antimicrobial stewardship by equipping them with the tools to improve patient knowledge of antibiotic use, symptom resolution and antimicrobial resistance using the TARGET antibiotic checklist, as well as other resources from the TARGET Antibiotics Toolkit.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf018"},"PeriodicalIF":3.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836887/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibiotic resistance in the Middle East and Southern Asia: a systematic review and meta-analysis.","authors":"Rachel Mathu, Elizabeth Diago-Navarro, Emily Lynch, Marie-Amélie Degail, Janet Ousley, Rupa Kanapathipillai, Justine Michel, Marc Gastellu-Etchegorry, Nada Malou","doi":"10.1093/jacamr/dlaf010","DOIUrl":"10.1093/jacamr/dlaf010","url":null,"abstract":"<p><strong>Introduction: </strong>Despite global surveillance efforts, antibiotic resistance (ABR) is difficult to address in low- and middle-income countries (LMICs). In the absence of country-wide ABR surveillance data, peer-reviewed literature is the next most significant source of publicly available ABR data. Médecins Sans Frontières conducted this review in hopes of using the pooled findings to inform treatment choices in the studied countries where sufficient local ABR data are unavailable.</p><p><strong>Methods: </strong>A systematic literature review reporting ABR rates for six infection sites in nine countries in the Middle East and Southern Asia was conducted. PubMed was used to identify literature published between January 2012 and August 2022. A meta-analysis of the included studies (<i>n</i> = 694) was conducted, of which 224 are reviewed in this paper. The JBI critical appraisal tool was used to evaluate risk of bias for included studies.</p><p><strong>Results: </strong>This paper focuses on sepsis, burns and wound infections, specifically, with the largest number of papers describing data from Iran, Türkiye and Pakistan. High (>30%) resistance to recommended first-line antibiotics was found. Gram-negative resistance to ceftriaxone, aminoglycosides and carbapenems was high in burn-related infections; colistin resistance among <i>Klebsiella pneumoniae</i> isolates in Pakistan was alarmingly high (81%).</p><p><strong>Conclusions: </strong>High-quality data on ABR in LMIC settings remain difficult to obtain. While peer-reviewed literature is a source of publicly available ABR data, it is of inconsistent quality; the field also lacks agreed reporting standards, limiting the capacity to pool findings. Nonetheless, high resistance to first-line antibiotics underscores the need for improved localized surveillance and stewardship.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf010"},"PeriodicalIF":3.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836886/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143457993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive analysis of antimicrobial resistance of clinical <i>emm</i>89 <i>Streptococcus pyogenes</i> in Japan.","authors":"Weichen Gong, Masayuki Ono, Masaya Yamaguchi, Daisuke Motooka, Yujiro Hirose, Kotaro Higashi, Momoko Kobayashi, Eri Ikeda, Tomoko Sumitomo, Rumi Okuno, Takahiro Yamaguchi, Ryuji Kawahara, Hitoshi Otsuka, Noriko Nakanishi, Yu Kazawa, Chikara Nakagawa, Ryo Yamaguchi, Hiroo Sakai, Yuko Matsumoto, Tadayoshi Ikebe, Shigetada Kawabata","doi":"10.1093/jacamr/dlaf017","DOIUrl":"10.1093/jacamr/dlaf017","url":null,"abstract":"<p><strong>Objectives: </strong><i>Streptococcus pyogenes</i> is involved in a wide range of diseases, including pharyngitis and life-threatening invasive infections. Increasing prevalence of antimicrobial resistance (AMR) has been reported worldwide in various bacteria, limiting the use of antibiotics in infection cases. The present study investigated the AMR of most prevalent <i>S. pyogenes emm</i> types, including <i>emm</i>89 strains in Japan.</p><p><strong>Methods: </strong>A total of 368 previously identified <i>S. pyogenes</i> isolates (311 <i>emm</i>89 strains and 57 of other <i>emm</i> types), which were previously isolated from patients with invasive and non-invasive infections throughout Japan, were used in the analyses. The minimum inhibitory concentrations of seven antibiotics, including penicillin-G, azithromycin (AZM) and clindamycin, were determined, and whole-genome sequences of AMR-associated genes were screened.</p><p><strong>Results: </strong>We identified 47 resistant strains, of which 91.49% (43/47) were resistant to AZM and/or clindamycin. A strong correlation was observed between non-invasive phenotypes and AMR. Whole-genome analysis indicated the wide distribution of three AMR-related genes, <i>ermT</i>, <i>folP</i> and <i>lmrP</i>, among the <i>emm</i>89 strains. Additionally, <i>tetO</i> was detected in tetracycline-resistance and <i>soxS</i> and <i>mel</i> was detected in chloramphenicol-resistance only in <i>emm</i>4 strains.</p><p><strong>Conclusions: </strong>The high prevalence of <i>S. pyogenes</i> resistance to AZM and/or clindamycin poses a threat to public health in Japan; thus, the development of next-generation antimicrobial therapies is imperative.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf017"},"PeriodicalIF":3.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836879/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143457990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma concentration of azithromycin and correlation with clinical outcomes in patients with enteric fever.","authors":"Rini Bandyopadhyay, Sumith K Mathew, Balaji Veeraraghavan, Prasanna Samuel, Jacob Backiyaraj, Sowmya Sathyendra, Priscilla Rupali","doi":"10.1093/jacamr/dlaf015","DOIUrl":"10.1093/jacamr/dlaf015","url":null,"abstract":"<p><strong>Background: </strong>Azithromycin is the only oral option available for XDR enteric fever. Studies correlating azithromycin levels with treatment success are rare.</p><p><strong>Methods: </strong>Serum azithromycin levels after administration of a once-daily 20 mg/kg dose for 7 days were measured in a single-centre prospective cohort of 25 consecutive adults with blood culture-positive enteric fever. Five blood samples were collected on Day 2 after starting azithromycin, i.e. 30 min before dosing (trough), and 2, 5, 12 and 24 h after dosing. The MIC was determined for all isolates and azithromycin plasma concentration was determined using LC-MS. Clinical and microbiological outcomes were documented.</p><p><strong>Results: </strong><i>Salmonella enterica</i> serovar Typhi accounted for 92% (<i>n</i> = 23) and <i>Salmonella enterica</i> serovar Paratyphi 8% (<i>n</i> = 2). Ten (40%) patients received IV azithromycin, and the rest received oral therapy. The median (IQR, range) MIC for azithromycin was 4 (4-6, 3-12) mg/L. Mean azithromycin plasma concentration ranges were: trough, 0.24 ± 0.19 mg/L; 2 h, 1.24 ± 0.98 mg/L; 5 h, 0.64 ± 0.51 mg/L; 12 h, 0.31 ± 0.16 mg/L; and 24 h, 0.37 ± 0.30 mg/L. The <i>C</i> _max/MIC and AUC/MIC for azithromycin were 0.29 ± 0.22 and 2.64 ± 1.64, respectively. The median (IQR, range) fever clearance time was 3 (2-3, 2-5) days and the length of hospital stay was 7 (5.5-12, 4-16) days. There was no clinical or microbiological failure, relapse or mortality.</p><p><strong>Conclusions: </strong>Azithromycin was effective in treatment of enteric fever, despite low extracellular azithromycin plasma levels.</p>","PeriodicalId":14594,"journal":{"name":"JAC-Antimicrobial Resistance","volume":"7 1","pages":"dlaf015"},"PeriodicalIF":3.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836883/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}