Journal of Antimicrobial Chemotherapy

BackgroundHospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP), particularly those caused by multi-drug resistant organisms (MDROs), often require newer antibiotic treatment. The efficacy and safety of newer antibiotics compared to generic antibiotics in randomized controlled trials (RCTs) have not been evaluated before. MethodsIn this systematic review, we searched RCTs in the United States National Library of Medicine (PubMed), Cochrane Central Reg...

ObjectivesTo provide real-world evidence on piperacillin exposure and outcomes in critically ill patients following the implementation of pharmacokinetic (PK)/pharmacodynamic (PD)-guided dosing in routine care. MethodsThis retrospective observational study included critically ill adults who received continuous piperacillin/tazobactam infusion between 2011 and 2019. Empiric doses were individualized using dosing software based on renal function and subsequently adjusted according to therapeutic ...

BackgroundThe United Nations General Assembly High-level Meeting on Antimicrobial Resistance (UNGA HLM-AMR) committed to a target that 70% of global human antibiotic use (ABU) should be from the Access group of the WHO AWaRe system. MethodsWe used 2019 IQVIA MIDAS(R) global ABU Quarterly value sales, volumes (kg/SU) and average ex-manufacturer prices to evaluate price per daily defined dose (DDD) by AWaRe group across countries. IQVIA MIDAS volumes/value data reflect public, private, or mixed s...

Background and objectivesCeftazidime-Avibactam (CAZ-AVI) is one of the last options to treat Enterobacteriales and Pseudomonas aeruginosa carbapenem-resistant. We aim to describe the susceptibility profile of bloodstream isolates of Enterobacterales and Pseudomonas aerunosa to ceftazidime-avibactam (CAZ-AVI) among strains resistant to third- and fourth-generation cephalosporins and/or carbapenems. MethodsWe conducted a retrospective descriptive study in two pediatric hospitals of Rio de Janeiro...

ObjectivesTo quantify how urine sample type and polymicrobial context impact antimicrobial resistance (AMR) in urinary tract infections (UTIs), using routine diagnostics at scale. MethodsIn this retrospective, single-centre study, we analysed 188,687 urine cultures from the Institute of Medical Microbiology, University of Zurich, Switzerland (January 2015 to May 2023). We compared midstream urine (MU), indwelling catheter (IDC), and intermittent catheter (IMC) samples. Samples were classified a...

Background Antibiotic pricing is a key determinant of access and stewardship in low- and middle-income countries (LMICs), yet empirical evidence on how prices are formed within pharmaceutical markets remains limited. However, there is little longitudinal evidence on how antibiotic prices behave within national pharmaceutical supply systems. This study evaluated the patterns and determinants of systemic antibiotic pricing in Tanzania using national regulatory import permit data. Methods We conduc...

BackgroundAntimicrobial resistance (AMR) represents one of the most serious threats to global public health, with a disproportionate burden borne by low- and middle-income countries. Rural healthcare settings in India remain under-represented in molecular AMR surveillance despite high antimicrobial use and limited diagnostic capacity. ObjectivesTo describe longitudinal phenotypic and molecular AMR patterns in clinical bacterial isolates from a rural district hospital in Gujarat, India, and to a...

AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSBackgroundC_ST_ABSEnsuring appropriate access to essential antibiotics is a critical global public health goal. The UN General Assembly agreed that 70% of global antibiotic use should be WHO Access group. A standard method to estimate optimal antibiotic use based on burden of disease, resistance and local context is needed to inform national policies. MethodsUsing data from multiple global datasets, we clustered 186 countries, territories and areas (CTAs) into p...

ObjectiveThe rapid availability of phenotypic antimicrobial susceptibility results is crucial for the timely detection of multidrug-resistant Gram-negative organisms and for guiding optimized treatment strategies. Recently, novel methods have been introduced that enable direct antimicrobial susceptibility testing (AST) from positive blood cultures. However, their performance has not yet been systematically compared in head-to-head evaluations. This study aimed to assess the analytical performanc...

IntroductionAs antibiotic resistant organisms and infections continue to proliferate globally, it becomes increasingly difficult to select empiric antibiotic therapy, particularly in patients who stand to benefit from early adequate treatment. The inappropriate treatment of suspected infection, including sepsis, can be both too narrow and too broad. There is a need to optimize and tailor selection of antibiotic therapy to each patient, such that those at risk for infections due to antibiotic res...

BackgroundPreoperative biliary stenting alters biliary colonization and may reduce the effectiveness of perioperative antibiotic prophylaxis in pancreatoduodenectomy. Although broader-spectrum regimens have been associated with improved infectious outcomes, their microbiological adequacy in routine clinical practice remains poorly defined. We therefore evaluated the real-world adequacy of a prolonged ampicillin-sulbactam protocol, its association with infectious outcomes and survival, and the po...

Linezolid is a critical last-resort antimicrobial for multidrug-resistant Enterococcus faecium, particularly against vancomycin-resistant lineages where therapeutic options are severely limited. While resistance has historically arisen through de novo chromosomal mutations, the global emergence of transferable resistance mechanisms threatens to render more infections untreatable. Here, we characterise a recent (2023-2024) hospital-associated outbreak of linezolid-resistant E. faecium in Queensla...

BackgroundHIV-specific broadly neutralising antibodies (bNAbs) can maintain viral control after interrupting antiretroviral therapy (ART). We investigated the duration and efficacy of Fc-engineered long-acting bNAbs (LS-bNAbs) in maintaining ART-free HIV control compared with placebo. MethodsRIO is a 1:1 randomised double-blind placebo-controlled trial of two LS-bNAbs (3BNC117-LS & 10-1074-LS) in individuals virally suppressed on ART initiated since early-stage HIV. Eligible participants interr...

We summarize an outbreak of N. gonorrhoeae ST16676 associated with disseminated gonococcal infections (DGIs) in Minnesota, USA in 2025. This novel strain replaced ST11184 as the predominant sequence type circulating among DGI cases in the state, encoded a porB1a allele, and carried a tetracycline resistance gene on a mobilizable plasmid.

IntroductionCentral line-associated bloodstream-infection (CLA-BSI) and catheter-related bloodstream infections (CR-BSI) remain a significant concern in pediatric inpatient units. ObjectiveTo analyze a case series of CLA-BSI and CR-BSI in hospitalized pediatric patients in hospitals with rigorous infection prevention measures. Materials and MethodsThis was an analytical, descriptive, and retrospective study conducted in patients aged 0 to 18 years, admitted between August 2023 and March 2025, ...

BackgroundClostridium perfringens can cause life-threatening extraintestinal infections in immunocompromised patients, an area in which we have little information regarding strain factors that impact patient risks and outcomes. MethodsWe conducted genomic-epidemiologic analyses on C. perfringens isolates from 70 patients seen at Brigham and Womens Hospital over 2021-2024. Genomic analyses evaluated strain profiles within a broader context of 2,321 C. perfringens genomes from foodborne, veterina...

Artificial intelligence (AI), particularly large language models (LLMs), is increasingly explored in healthcare, yet its real-world usability and safety in high-risk clinical pharmacy tasks remain uncertain. Vancomycin therapeutic drug monitoring (TDM), which requires precise pharmacokinetic calculations and context-sensitive interpretation within a narrow therapeutic window, provides a stringent test case for AI-assisted decision support. This proof-of-concept study developed and evaluated a hy...

BackgroundHealthcare-associated carbapenemase-producing Enterobacterales (CPE) outbreaks are a major healthcare challenge. Epidemiological studies have identified patient-level risk factors for CPE transmission, and genomic studies have highlighted high-risk lineages or mobile genetic elements (MGEs); however, a unified dissemination risk-prediction framework is lacking. ObjectivesTo synthesise available data on epidemiological, microbiological and genomic risk factors to quantify healthcare-as...

BackgroundAntibiotic stewardship during stem cell transplantation (SCT) is challenging.. Procalcitonin (PCT) has been employed successfully in critical care patients to safely guide stewardship. However, procalcitonin guided stewardship has not been robustly assessed in SCT recipients. We sought to evaluate the potential utility of PCT to guide antimicrobial de-escalation during engraftment. Methods100 SCT patients were prospectively enrolled in a "strategy trial" and had infectious complicatio...

From 2021 to 2025, MRSA emerged as a major multidrug-resistant pathogen in the study area. Among 545 S. aureus isolates, 67.2% were MRSA, disproportionately affecting children under five (26.5%) and males (55.5%). Case incidence more than doubled by 2025, suggesting rising transmission or resistance. Most isolates were hospital-associated (85.2%), predominantly from outpatients (88.5%), with middle ear discharge as the main source (67%). Gentamicin showed the highest susceptibility (72.1%), whil...