JAC-Antimicrobial Resistance最新文献

Background and objective: Antimicrobial resistance (AMR) is a critical global health threat, fuelled by inappropriate antibiotic use. In Palestine, dispensing antibiotics without prescription remains common despite legal restrictions, but limited qualitative evidence exists on pharmacists' perspectives. The objective was to explore community pharmacists' practices, perceptions, and challenges in dispensing antibiotics without prescription in Palestine.

Methods: This qualitative descriptive study used semi-structured, in-depth interviews with 14 licensed pharmacists from urban, semi-urban, and rural districts of the West Bank, conducted between January and March 2025. Purposive sampling ensured variation in gender, experience, and setting. Interviews were audio-recorded, transcribed verbatim, and analyzed thematically using Braun and Clarke's framework. Six major themes were identified.

Results: Participants were aware of the legal prohibition but cited weak enforcement. Daily non-prescription requests were common, especially during seasonal illnesses, driven by prior positive experiences, social recommendations, and inability to afford doctor visits. Symptom-based dispensing was used in perceived 'clear cases,' influenced by customer pressure and business competition. Public misconceptions-such as believing antibiotics treat viral infections-were widespread, with frequent incomplete dosing and reuse of leftovers. Pharmacists attempted patient education but faced time and receptiveness barriers, and often experienced ethical conflict. Regulatory oversight was minimal; participants recommended stricter inspections, public awareness campaigns, and collaborative practice models.

Conclusions: Non-prescription antibiotic dispensing in Palestine is shaped by patient demand, economic pressures, and weak regulation. Addressing these drivers requires strengthened enforcement, targeted public education, professional training, and integration of pharmacists into AMR stewardship to safeguard public health. These findings highlight the need for actionable reforms in pharmacy practice and national policy, including stricter regulatory oversight and pharmacist-led public education, to reduce inappropriate antibiotic use and strengthen AMR containment strategies.

Background: The US elderly population (≥65 years old) increased markedly in the last decades, and infections are responsible for approximately one-third of all deaths in this population. We evaluated the antimicrobial susceptibility of Enterobacterales causing infection in elderly patients in US hospitals.

Methods: Unique patient clinical isolates were consecutively collected from 72 US hospitals in 2021-2023 and tested for susceptibility by broth microdilution. Results for 10 574 Enterobacterales from elderly patients were analysed and compared with 9793 isolates from adult patients (18-64 years old). Carbapenem-resistant Enterobacterales (CRE) were screened for carbapenemases by whole-genome sequencing.

Results: All isolates from elderly patients were inhibited at aztreonam-avibactam MIC of ≤8 mg/L (>99.9% susceptible at ≤4 mg/L). Ceftazidime-avibactam and meropenem-vaborbactam were very active against Enterobacterales overall (≥99.7% susceptible) but exhibited limited activity against CRE (70.4%-71.6% susceptible). The most active agents against CRE were aztreonam-avibactam (98.8% susceptible), cefiderocol (96.3% susceptible) and tigecycline (96.3% susceptible). Susceptibility rates of isolates from the elderly were comparable (±≤ 2.6%) with those from the adult population; however, the frequencies of CRE and MDR phenotypes were lower among the elderly than adults. The most common carbapenemase among CREs from elderly patients were Klebsiella pneumoniae carbapenemases (55.6% of CRE) and NDM (24.7%); a metallo-β-lactamase was identified in 28.4% of CRE isolates.

Conclusions: Enterobacterales causing infections in the elderly population showed a similar antimicrobial resistance profile but a lower frequency of CRE and MDR isolates to those causing infection in the adults.

Background: Rapid antibiotic initiation is essential for managing potential infections following chemotherapy-induced neutropenia. However, excessive use of broad-spectrum antibiotics should be avoided. Implementing antimicrobial stewardship (AMS) in haematology units is challenging due to high infection-related risks, and data on interventions remain scarce. This study aimed to evaluate the safety of an AMS bundle on a haematology ward.

Methods: A prospective cohort study was conducted at a tertiary care centre among patients with high-risk (≥7 days) neutropenia. The AMS bundle consisted of replacing empirical meropenem with ceftazidime, and shortening treatment duration to 2 days in case of defervescence and negative blood cultures. Data on ICU admission, all-cause mortality, antimicrobial use and microorganisms identified were compared with a (retrospective) pre-intervention cohort.

Results: A total of 396 patients were included (206 pre-intervention, 190 post-intervention). Allogeneic stem cell transplantations increased from 21% pre-intervention to 37% post-intervention. There was no statistical difference in the adjusted composite endpoint of ICU admission and all-cause mortality [adjusted HR (aHR) 1.46; 95% CI, 0.76-2.81; P = 0.26]. Pre-intervention, meropenem was prescribed in 99% of patients, which shifted to ceftazidime in 78% post-intervention. Median antibiotic treatment duration decreased from 8.0 to 5.0 days (P < 0.001), and empirical antibiotic consumption decreased from 12 to 8 days of therapy per patient (P < 0.001). Bloodstream infections with Candida spp. decreased from 17 pre-intervention to 5 post-intervention (P = 0.03).

Conclusions: The AMS bundle led to a shift towards narrower-spectrum antibiotics, and reduced treatment duration and overall antibiotic use without a significant impact on the primary safety outcome. The intervention was accompanied by a declining trend in candidaemia incidence.

Background and objectives: There are few Australian data regarding the burden of hospital-onset bloodstream infections (HO-BSIs). To quantify the impact of antimicrobial-susceptible and -resistant HO-BSIs on patient outcomes by augmenting laboratory-based surveillance data.

Methods: We performed a retrospective cohort study at a tertiary referral hospital in Melbourne, Australia, from 2015 to 2020. We linked administrative data with bloodstream infection surveillance data from the Australian Group on Antimicrobial Resistance. We performed cause-specific Cox proportional hazards regression to quantify the impact of HO-BSI on inpatient mortality and discharge alive, with separate models for Enterobacterales, Staphylococcus aureus, Enterococcus species and the non-fermenting Gram-negative bacilli (NFGNB), Pseudomonas aeruginosa and Acinetobacter species, compared to admissions without HO-BSI. Excess length of stay (LOS) was estimated using multistate models.

Results: The cohort of 278 984 admissions included 814 (0.3%) HO-BSIs. Enterobacterales were the most frequent pathogens, followed by enterococci, S. aureus and NFGNB (incidence 3.62, 2.34, 1.11 and 0.80 events per 10 000 patient-days, respectively). Both antimicrobial-resistant and -susceptible HO-BSI increased risk of death and LOS compared with admissions without HO-BSI. Antimicrobial-resistant and -susceptible HO-BSIs, respectively, increased LOS by 5.7 days (95% CI: 4.9-6.5) and 4.1 days (95% CI: 3.8-4.5) for Enterobacterales, 4.9 days (95% CI: 4.5-5.4) and 3.1 days (95% CI: 2.6-3.6) for enterococci, and 6.3 days (95% CI: 5.3-7.3) and 9.8 days (95% CI: 9.1-10.5) for S. aureus.

Conclusions: Antimicrobial-susceptible and -resistant HO-BSIs have a substantial impact on patient outcomes. We demonstrated the feasibility of leveraging a national laboratory-based surveillance system to quantify the impact of HO-BSI.

Objective: To assess the antibiotic resistance and beta-lactam resistance genes among bacterial isolates from clinical, river water and poultry samples.

Methods: Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were isolated from clinical, poultry and river water samples collected during 2020-22. They were subjected to antimicrobial susceptibility tests following the CLSI guidelines. The bacteria were screened for β-lactam resistance genes bla _TEM, mcr-1, mecA and bla_NDM-1 .

Results: Among 2835 clinical samples, E. coli was the most frequently isolated bacterium (10.3%, 292), followed by S. aureus (6.0%, 169) and P. aeruginosa (4.0%, 143). Of the E. coli isolates, 64.4% exhibited multidrug resistance (MDR) and 43.8% were extended-spectrum β-lactamase (ESBL) producers, with 44.5% and 16.4% harbouring the blaTEM and mcr-1 genes, respectively. Among S. aureus isolates, 80.9% of methicillin-resistant strains (MRSA) carried the mecA gene, while 30.1% of metallo-β-lactamase (MBL)-producing P. aeruginosa were positive for the blaNDM-1 gene. In poultry samples, 30.4% of E. coli isolates harboured the blaTEM gene among 128 ESBL producers, and the prevalence of colistin-resistant isolates carrying mcr-1 was higher than in clinical samples. In contrast, the occurrence of ESBL-producing E. coli and MRSA, along with their associated resistance genes, was lower in water samples.

Conclusions: This study demonstrated widespread multidrug resistance (MDR) and ESBL production among clinical, poultry and river water bacterial isolates in the Kathmandu valley. Colistin-resistant E. coli carrying the mcr-1 gene, methicillin-resistant S. aureus (MRSA) with mecA and metallo-β-lactamase (MBL)-producing P. aeruginosa harboring blaNDM-1 were detected across sources. These findings emphasize an urgent One Health approach to curb the growing threat of antimicrobial resistance in the region.

Background: Although Japanese guidelines recommend fluoroquinolones (FQs) and cephalosporins for AUC (acute uncomplicated cystitis) treatment, the emergence of FQ-resistant uropathogens and inappropriate use of antibiotics may lead to treatment failure (TF), and increased healthcare costs. There is a need to understand the epidemiology, treatment patterns, and healthcare cost implications associated with AUC in Japan.

Methods: This retrospective cohort study used the Japanese Medical Database Centre database (1 October 2015-30 November 2021). Female patients (≥18 years) had an AUC diagnosis in the same month as ≥1 oral antibiotic prescription claim in the outpatient setting. The population was stratified into cohorts by TF status and history of AUC recurrence prior to index (pre-index recurrence). Baseline demographics were evaluated in the 12-month pre-index period and age standardized prevalence of AUC was calculated. Treatment patterns and AUC-related costs [2022 Japanese Yen (¥)], were reported for the post-index follow-up period.

Results: Of 71 476 total patients, 62.46% were aged <50 years. Patients had evidence of TF (n = 3742; 5.24%) and pre-index recurrence (n = 3206; 4.49%). The age standardized prevalence of AUC (2016-2021) decreased from 8.62% to 6.02%, with up to 3.9 million women affected each year. A high proportion of patients with TF received FQs (45.48%) and third generation cephalosporins (43.37%). The mean total AUC-related costs were ¥14 905 and pharmacy costs were ¥1059 per patient, per index AUC episode.

Conclusion: Healthcare providers should consider the cost implications for patients with antibiotic TF or a history of AUC recurrence when selecting antibiotics for empiric treatment in Japan.

Aim: Multidrug-resistant (MDR) Gram-negative bacilli pose a significant threat in neonatal care. This study aimed to evaluate the point prevalence and molecular characteristics of intestinal MDR colonization in neonates at Muhimbili National Hospital, Tanzania.

Method: We conducted a point prevalence study with faecal samples from 51 neonates born ≥26 weeks gestational age (41% girls, mean 31.6 ± 3.8 weeks) admitted to the neonatal intensive care unit (NICU) at Muhimbili National Hospital on 17 May 2022. The median age at sampling was 8 days (interquartile range 11 days). Samples were cultured on chromogenic agar, and positive colonies underwent antimicrobial susceptibility testing. Whole-genome sequencing and plasmid analysis using Optical DNA Mapping (ODM) were performed on carbapenem-resistant isolates.

Results: Among the 51 neonates, 31 (60.7%) were colonized by ESBL-producing Klebsiella pneumoniae (EP-KP) and/or Escherichia coli (EP-EC). Of these, 15 isolates were carbapenem-producing Enterobacteriaceae (CPE) harboring bla _NDM-5, bla _CTX-M-15, and eight also carried bla _OXA-181. The most prevalent carbapenemase-producing Klebsiella pneumoniae (CP-KP) sequence type (ST) was ST437, part of the high-risk clonal complex CC11, while the most common carbapenemase-producing E. coli (CP-EC) was ST167. Both CP-KP and CP-EC were MDR isolates encoding bla _CTX-M-15 and bla _NDM-5. Optical DNA Mapping showed that the bla _NDM-5 encoding plasmids in at least six carbapenem-producing isolates (four KP ST437 and two EC ST167) were similar, suggesting plasmid transfer.

Conclusion: A high prevalence of colonization with high-risk clones was observed in neonates, highlighting the urgent need for strengthened MDR-surveillance, infection control, and antibiotic stewardship in the NICU at MNH.

Objectives: To survey the current antibiotic and antifungal drug practices of UK neonatal intensive care units (NICUs), and to identify antibiotic preferences and policies for treatment of early- and late-onset sepsis (EoS and LoS), meningitis, and antifungal prophylaxis.

Methods: Between January and May 2024, we contacted all 53 tertiary-level UK NICUs via telephone and/or e-mail. We requested a copy of each unit's guidelines for antibiotic treatment of EoS and LoS, and antifungal prophylaxis.

Results: We obtained guidelines from 53/53 (100%) units. A penicillin and aminoglycoside combination was the consistent first-line recommendation for EoS in 51/53 (96%) units. Only a minority (11/53; 21%) units specified any second-line antibiotic regimen for EoS, though most (44/53; 83%) specifically recommended amoxicillin for suspected listeriosis. For LoS, almost all NICUs (52/53; 98%) provided specific guidance on empirical first-line antibiotic treatment, with empirical narrow-spectrum antibiotics as first-line LoS treatment for term neonates in 42/53 (79%) NICUs and for preterm neonates in 41/53 (77%) NICUs. Fifty-four percent (29/53) of units included specific LoS recommendations for neonates with indwelling central venous catheters. Sixty-six percent (35/53) of NICUs included cefotaxime in their empirical meningitis regimens. Eighty-five percent (45/53) of units had clear guidelines for antifungal prophylaxis.

Conclusions: While EoS treatment was consistent across units, there remained wide variation in antibiotic regimens used for LoS and meningitis, and for neonates with indwelling central venous catheters. Guidelines specific to preterm neonates were limited. The practice of routine antifungal prophylaxis has been more prevalent since the last UK survey in 2006-07 but is still neither universal nor consistent.