Trends, Epidemiology, and Management of Multi-Drug Resistant Gram-Negative Bacterial Infections in the Hospitalized Setting

Bioinspired synthesis and characterization of chitosan-based MgO nanoparticles: Evaluating antibacterial potential against MDR pathogens and anticancer activity in HEPG2 cell lines

The growing antibacterial resistance threatens the public health and medical sector. The concern necessitates the innovative and environmentally friendly solution which is addressed in the current study by synthesis of eco-friendly biopolymer-based metallic oxide nanoparticles using green synthesis, offering a sustainable alternative to conventional approaches. Chitosan-based magnesium oxide (CH-MgO) nanoparticles were synthesized using leaf extract of Trianthema portulacastrum. Different analytical techniques, such UV-vis, SEM, TEM, EDX, FTIR, and XRD, were used to characterize the nanoparticles. Further investigations were carried out to determine the antibacterial and antibiofilm activities against Enterococcus faecium, Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa. The anticancer activity was evaluated via MTT assay against HePG2 cell lines, which were microscopically examined. The characterizations confirmed the UV-absorption peak at 290 nm, 20 nm crystallite size, crystalline structure, and roughly spherical morphology. For the well diffusion assay, inhibition zones were obtained in the range of 4 ± 0.40 mm-19 ± 1.72 mm. Successful biofilm inhibitions of 50 % against all isolates and maximum cytotoxicity of 83 % against HePG2 cell lines were also achieved for the nanoparticles. The investigation affirms the prospects of CH-MgO nanoparticles as antibacterial agent against drug-resistant pathogens and establishes its anticancer activity against cancer cells. The findings of the study suggest the prospects of eco-friendly nanomaterial for biomedical and therapeutic purposes.

Deciphering the chemical constituents and antimicrobial activity of Prangos pabularia Lindl. using LC-MS/MS in combination with experimental evaluation and computational studies

This study meticulously explores the antimicrobial potential of Prangos pabularia Lindl.'s aerial parts through a comprehensive blend of in vitro and in silico analysis. Extracts with varying polarities underwent LC-MS/MS identification of active components, followed by in vitro and in silico assessments of antimicrobial efficacy against Escherichia coli, Bacillus cereus, Candida albicans, Candida glabrata, and Candida paropsilosis. The methanolic extract exhibited significant antimicrobial activity with a MIC value of 48 μg/mL against all tested strains. Molecular docking revealed the compound 9-(3-methylbut-2-enoxy)-furo-(3,2-g)-chromen-7-one's highest binding affinity against the penicillin-binding protein (PBP) bacterial drug target molecule. Other compounds also displayed substantial interactions with key antimicrobial drug target proteins. Further, Molecular dynamics simulations affirmed the stability of protein and ligand conformations. Collectively, these results underscore Prangos pabularia Lindl.'s aerial parts as a promising botanical resource in combating diverse microbial infections. This comprehensive approach not only validates it's in vitro antimicrobial properties but also provides molecular insights into interaction mechanisms, advancing our comprehension of the plant's therapeutic potential.

Bioassay-guided isolation of antibacterial and anti-biofilm compounds from Peltophorum africanum Sond. Stem and mechanisms of active fractions against nosocomial pathogens

ETHNOPHARMACOLOGICAL RELEVANCE

Peltophorum africanum is widely used in indigenous medicine to treat infections, wounds, and inflammatory conditions. This study employs a bioassay-guided approach to isolate antibacterial compounds elucidating their pharmacological mechanisms and supporting their potential as sources of anti-infective agents.

AIM OF THE STUDY

The study aimed to investigate P. africanum stem as a potential source of novel compounds for drug discovery, emphasizing its antibacterial, antibiofilm, and antioxidant properties.

MATERIALS AND METHODS

Chromatographic techniques were used to fractionate and isolate antibacterial compounds. Structural elucidation was performed using NMR and LC-MS. Antioxidant activity was assessed using the DPPH radical scavenging assay. Antibacterial activity was determined using the microbroth dilution method against Pseudomonas aeruginosa and Staphylococcus aureus. Anti-biofilm activity was evaluated using the crystal violet staining method. The antibacterial mechanism of action of the most active fraction was examined by assessing changes in INT-dehydrogenase activity and monitoring the leakage of intracellular proteins and DNA.

RESULTS

Betulinic acid-3-3,4-dihydroxybenzoate and 3-octadecanoyl stigmasterol were isolated from the hexane crude extract. LC-MS identified 13 compounds. The plant samples MIC varied from 0.31 to 1.25 mg/mL. Isolated compounds had noteworthy activity across all biofilm phases. The fraction exhibited the lowest number of viable cells when assessing INT-dehydrogenase activity. Additionally, it was more effective in causing the release of intracellular proteins and DNA, while also displaying superior antioxidant activity.

CONCLUSION

The ability of antioxidant and antibacterial compounds of the P. africanum stem to inhibit biofilm formation and eradication of mature biofilms holds promise for the treatment of biofilm-associated nosocomial infections.

Antimicrobial stewardship interventions in hospitalized adults with community-acquired pneumonia: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis evaluate the effectiveness of ASPs in managing community-acquired pneumonia (CAP), focusing on antibiotic optimization and resistance mitigation.

METHODS

Comprehensive literature searches were conducted in PubMed, Scopus, and Web of Science using PICOS criteria. Studies involving adults with CAP exposed to ASPs were included. Data on clinical, economic, diagnostic, and treatment outcomes were extracted. Random-effects meta-analysis using R software pooled effect sizes. Outcomes reported in at least three studies were analyzed for robustness.

RESULTS

ASPs did not significantly impact in-hospital mortality, length of stay, 30-day readmissions, sample collection rates, or intravenous antibiotic duration. However, notable improvements included shorter time to clinical stability and a 31% reduction in 30-day mortality. Legionella urinary antigen testing frequency increased nearly threefold, and the time from admission to antibiotic initiation was reduced. Enhanced adherence to timely antibiotic administration and recommended regimens was observed, though outcome variability persisted.

CONCLUSION

ASPs significantly improve CAP management by enhancing clinical stability and accelerating antibiotic initiation. Multifaceted strategies, including rapid diagnostics and clinician education, yield clinical benefits. However, outcome variability suggests a need for tailored interventions. Future research should isolate specific ASP components influencing prescriber behavior. Ongoing investment in education, diagnostics, and interdisciplinary collaboration is vital to optimize CAP treatment and combat antibiotic resistance.

A systematic review of the avian antibody (IgY) therapeutic effects on human bacterial infections over the decade

The overuse of antibiotics worldwide, especially during the Coronavirus pandemic, has raised concerns about the rise of antibiotic resistance and its side effects. Immunoglobulin Y, a natural protein that specifically targets foreign antigens, holds promise as a potential therapeutic option, particularly for individuals with sensitive immune systems. Despite numerous studies on IgY, the optimal administration method, effective dose, target antigen, and potential side effects of this antibody remain areas of active research and challenge. This review selected and evaluated articles published in the last ten years from databases such as PubMed and Science Direct with appropriate keywords discussing the therapeutic effects of immunoglobulin Y in human infections in vivo. Out of all the reviewed articles, 35 articles met the inclusion criteria. The results showed that the specific antibody against dental, respiratory, and skin infections has an acceptable effectiveness. In contrast, some infections, such as neurological infections, including tetanus and botulism, still need further investigation due to the short survival time of mice. On the other hand, reporting side effects such as antibody-dependent enhancement in some infections limits its use.

Incidence, Compliance, and Risk Factor Associated with Central Line-Associated Bloodstream Infection (CLABSI) in Intensive Care Unit (ICU) Patients: A Multicenter Study in an Upper Middle-Income Country

Background: Despite significant prevention efforts, the incidence of central line-associated bloodstream infection (CLABSI) in intensive care units (ICUs) is rising at an alarming rate. CLABSI contributes to increased morbidity, mortality, prolonged hospital stays and elevated healthcare costs. This study aimed to determine the incidence rate of CLABSI, compliance with the central venous catheter (CVC) care bundle and risk factors associated with CLABSI among ICU patients. Method: This prospective observational study was conducted in one university hospital and two public hospitals in Malaysia between October 2022 to January 2023. Adult ICU patients (aged > 18 years) with CVC and admitted to the ICU for more than 48 h were included in this study. Data collected included patient demographics, clinical diagnosis, CVC details, compliance with CVC care bundle and microbiological results. All data analyses were performed using SPSS version 23. Results: A total of 862 patients with 997 CVCs met the inclusion criteria, contributing to 4330 central line (CL) days and 18 CLABSI cases. The overall incidence rate of CLABSI was 4.16 per 1000 CL days. The average of overall compliance with CVC care bundle components was 65%. The predominant causative microorganisms isolated from CLABSI episodes were Gram-negative bacteria (78.3%), followed by Gram-positive bacteria (17.4%) and Candida spp. (2.0%). Multivariate analysis identified prolonged ICU stay (adjusted odds ratio (AOR): 1.994; 95% confidence interval (CI): 1.092-3.009), undergoing surgery (AOR: 2.02, 95% CI: 1.468-5.830) and having had multiple catheters (AOR: 3.167, 95% CI: 1.519-9.313) as significant risk factors for CLABSI. Conclusions: The findings underscore the importance of robust surveillance, embedded infection-control and -prevention initiatives, and strict adherence to the CVC care bundle to prevent CLABSI in ICUs. Targeted interventions addressing identified risk factors are crucial to improve patient outcomes and reduce healthcare costs.

Antibacterial activity of the endophytic fungal extracts and synergistic effects of combinations of ethylenediaminetetraacetic acid (EDTA) against Pseudomonas aeruginosa and Escherichia coli

The growing threat of antibiotic resistance in bacteria is a critical public health concern. Combining natural compounds with antimicrobial agents is an alternative approach to improve the antibacterial efficacy and safety of these agents. The strategy is to restore the effectiveness of existing antibiotics while minimizing the required concentrations of antibiotics or antimicrobial agents. This study aimed to isolate the endophytic fungi from medicinal plants, including Lantana camara, Orthosiphon aristatus, Mansonia gagei, Terminalia bellirica, Oroxylum indicum, Elaeagnus latifolia, Talinum paniculatum, and Capsicum annuum, and evaluate the combined antibacterial efficacy with selected antibiotics or ethylenediaminetetraacetic acid (EDTA) against Pseudomonas aeruginosa. The antimicrobial activity of the extracts was assessed using agar well diffusion and broth microdilution methods. The minimum inhibitory concentration (MIC) values of the extracts were 32-64 µg/mL against Escherichia coli, and 512-2,048 µg/mL against P. aeruginosa, respectively. Time-kill assays demonstrated the bacteriostatic effect of the extracts. The checkerboard microbroth dilution method was performed to determine the synergistic effect between endophytic fungal extracts and antibiotics or EDTA. The synergistic effect was observed in the extractions of endophytic fungi isolated from M. gagei, T. bellirica, O. indicum, E. latifolia, T. paniculatum, and C. annuum combined with EDTA against P. aeruginosa. Combinations of endophytic fungi with EDTA, which exhibited a synergistic effect, demonstrated bactericidal action against Gram-negative bacteria. The present study suggests that combining endophytic fungal extracts and EDTA could be an essential strategy for combating pathogenic Gram-negative bacteria.

Observed Prevalence and Characterization of Fluoroquinolone-Resistant and Multidrug-Resistant Bacteria in Loggerhead Sea Turtles (Caretta caretta) from the Adriatic Sea

Background/Objectives: Antimicrobial resistance (AMR) is a major global health concern with profound implications for human, animal, and environmental health. Marine ecosystems are emerging as reservoirs of resistant bacteria due to contamination from anthropogenic activities. This study aimed to investigate fluoroquinolone-resistant and multidrug-resistant bacteria in loggerhead sea turtles (Caretta caretta). Methods: Cloacal swabs were collected from 28 loggerhead sea turtles at a rescue center in southern Italy. Swabs were cultured in nutrient media supplemented with enrofloxacin. Bacterial isolates underwent identification by MALDI-TOF, antimicrobial susceptibility testing, and assessment for multidrug resistance. Conjugation experiments evaluated the transferability of enrofloxacin resistance. Results: Thirty-six enrofloxacin-resistant bacterial strains were isolated from 22 turtles. The identified species included Vagococcus fluvialis (13 strains), Citrobacter freundii (5), Escherichia coli (6), and Pseudomonas mendocina (4). Thirty-five isolates exhibited multidrug resistance, with resistance to critically important antibiotics such as imipenem observed in C. freundii and Enterobacter faecium. Conjugation experiments showed no transfer of resistance genes. Conclusions: The study highlights the prevalence of fluoroquinolone-resistant and multidrug-resistant bacteria in C. caretta, implicating marine environments as reservoirs of AMR. The findings underscore the need for stricter regulation of antimicrobial use and monitoring of resistance dissemination in marine ecosystems. These results contribute to understanding AMR dynamics within the One Health framework, emphasizing the interconnectedness of environmental, animal, and human health.

Synthesis, characterization, and biomedical applications (antibacterial, antibiofilm, anticancer and effects on hospital-acquired pneumonia infection) of copper titanium oxide nanostructures

Hospital-acquired pneumonia (HAP) is the second most common cause of nosocomial infections and is responsible for 15% of nosocomial infections, with a high mortality rate, which has led to increased concern and significant costs in healthcare settings. The most significant agents of HAP are Pseudomonas aeruginosa and Klebsiella pneumoniae, which create a biofilm that results in a resistant infection. We aimed to study the synthesis of Cu2Ti2O5 nanoparticles, their effects on the growth and biofilms of Pseudomonas aeruginosa and Klebsiella pneumoniae isolated from respiratory infections, and their anticancer effects. In this study, for the first time, the Pechini method was used to synthesize Cu2Ti2O5 nanostructures. The effects of nanoparticles on the growth and biofilms of Pseudomonas aeruginosa and Klebsiella pneumoniae were evaluated using a microdilution broth and the microtiter plate method, and the cytotoxic effect of the nanoparticles on the A549 cell line was also assessed by MTT. The characteristics of the nanoparticles were confirmed through XRD, FTIR, SEM, and TEM techniques. Cu2Ti2O5 showed a minimum inhibitory effect in concentrations of 156.25 to 625 μg mL-1 for ten isolates of K. pneumoniae and 625 to 1250 μg mL-1 for ten isolates of P. aeruginosa and at sub-MIC concentrations as well. It reduced the biofilms of K. pneumoniae and P. aeruginosa strains by 75% and 44.4%. The nanoparticles killed 50% of A549 cancer cells in 48 h at concentrations of 30 to 40 μg mL-1 and in 24 h at concentrations of 200 to 250 μg mL-1. The findings of this study show the antibacterial, anti-biofilm, and anti-cancer effects of Cu2Ti2O5 nanoparticles. Therefore, these nanoparticles can be considered potential antimicrobial candidates; however, these effects should be confirmed with more bacterial isolates.

Trends in Healthcare-Acquired Infections Due to Multidrug-Resistant Organisms at a German University Medical Center Before and During the COVID-19 Pandemic

BACKGROUND

Healthcare-acquired infections due to multidrug-resistant organisms (MDR-HAIs) pose globally significant challenges to healthcare systems, leading to increased morbidity, mortality, and healthcare costs. According to the World Health Organization, the COVID-19 pandemic significantly impacted the burden of MDR-HAIs. The aim of this study was to investigate the dynamics and epidemiology of MDR-HAIs in inpatients at the University of Leipzig Medical Center (ULMC) before and during the COVID-19 pandemic.

METHODS

We compared data from inpatients with bacterial infections from 2017 to 2019 (pre-COVID-19) and from 2021to 2023 (during COVID-19) in a cross-sectional, monocentric, retrospective survey. This study focused on selected multidrug-resistant organisms (MDROs) and four clinical specimens. We analyzed the risk factors for MDR-HAIs using logistic regression models.

RESULTS

Out of 342,705 inpatients, 32,206 were diagnosed with a bacterial infection. The prevalence increased significantly from 8.09% (pre-COVID-19) to 10.79% (during COVID-19) (p < 0.001), but the proportion of MDROs decreased from 10.14% to 8.07%. The proportions of MDR-HAIs were 59.86% and 56.67%, respectively. The proportion of carbapenem-resistant Klebsiella pneumoniae and Enterobacter cloacae increased significantly. The risk of MDR-HAIs during COVID-19 decreased by 18% compared to pre-COVID-19 (p = 0.047). Longer hospital stays increased the risk of MDR-HAIs in both periods. This risk significantly decreased for children and the elderly during COVID-19.

CONCLUSION

These findings show that it is also important to analyze epidemiological data at the facility level in order to evaluate the effectiveness of infection control practices even during unprecedented health crises like the COVID-19 pandemic.

Seasonal Trends and Antibiotic Resistance Profiles of Bacterial Pathogens in Indian Clinical Isolates

Introduction Bacterial diseases exhibit seasonal trends, necessitating their monitoring for outbreak prediction, treatment optimization, and infection control. This study explores seasonal trends, temperature correlations, and antimicrobial resistance profiles of key pathogens in an Indian tertiary care setting. Methodology This cross-sectional study analyzed bacterial isolates from 1,562 patient samples, including Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, and Enterococcus faecalis. Monthly infection rates and seasonal patterns were visualized using heatmaps and time-series graphs. Pearson's correlation assessed the relationship between these infection rates and temperature. Antibiotic susceptibility was evaluated using VITEK2, with resistance patterns visualized in R. Results Infections peaked in April (n = 163, 10.43%) and March (n = 161, 10.30%), with S . aureus as the most common pathogen (n = 271, 25.64%), followed by K . pneumoniae (n = 201, 19.02%) and P . aeruginosa (n = 178, 16.84%). Seasonal trends showed S. aureus infections peaked in summer (n = 45, 16.6%), while P. aeruginosa (n = 27, 15.2%) and E. faecalis (n = 24, 25.5%) peaked in winter. Temperature correlated positively with S. aureus infection (r = 0.814, P = 0.001) and negatively with P. aeruginosa (r = -0.845, P = 0.001), and E . faecalis (r = -0.618, P = 0.032), with no correlation observed for K. pneumoniae, A. baumannii, and E. coli. Multi-drug resistance (MDR), extensively drug resistance (XDR), and pandrug resistance were more prevalent in Gram-negative than in Gram-positive bacteria.  Conclusions This study reveals temperature-driven seasonal patterns in bacterial infections, aiding outbreak prediction and prevention. The findings emphasize the threat of multidrug resistance, particularly in Gram-negative bacteria, reinforcing the need for enhanced infection control and targeted antibiotic stewardship.

Investigation of the Effects of Fosfomycin in Kidney Damage Caused by CLP-Induced Sepsis

Sepsis, a life-threatening condition characterized by dysregulated host responses to infection, often leads to multi-organ dysfunction, including kidney injury. Kidney damage in sepsis can have severe consequences and is associated with high mortality rates. This study aimed to investigate the potential therapeutic effects of fosfomycin (FOS), a broad-spectrum antibiotic with immunomodulatory properties, on kidney damage induced by cecal ligation and puncture (CLP)-induced sepsis in a rodent model. In total, 24 rats were randomly divided into three groups. Group 1 (n = 8), the healthy control group (C), received a single dose of 0.9% NaCl (saline) solution via an intraperitoneal (i.p.) route. To group 2 (n = 8), the CLP group, CLP-induced sepsis was applied without medication, and a single dose of 0.9% NaCl (saline) solution was applied i.p. before induction. To group 3 (n = 8), the CLP + FOS (500 mg/kg) group, a single dose of 500 mg/kg FOS was administered i.p. before sepsis induction. The effects of fosfomycin on kidney function, histopathological changes, inflammatory markers, oxidative stress, and apoptosis were assessed. In the fosfomycin-treated group, the histological analysis results demonstrated reduction in kidney tissue damage and inflammation. Additionally, fosfomycin attenuated the upregulation of pro-inflammatory cytokines and reduced oxidative stress markers in kidney tissue. Furthermore, fosfomycin treatment was associated with a decrease in apoptotic cell death in the kidney. These findings suggest that fosfomycin may have a protective effect on kidney damage caused by CLP-induced sepsis. The potential mechanisms underlying this protection include the modulation of inflammation, reduction of oxidative stress, and inhibition of apoptosis.

Susceptibility of various Gram-negative bacteria to antibacterial agents: SMART in China 2019-2020

BACKGROUND

The Study for Monitoring Antimicrobial Resistance Trends (SMART) is an international surveillance program longitudinally monitoring aerobic and facultative Gram-negative bacteria (GNB) involvement in infections and their antimicrobial resistance profiles. Here the incidence and resistance patterns of Chinese GNB isolates from bloodstream infections (BSI), intraabdominal infections (IAI), respiratory tract infections (RTI) and urinary tract infections (UTI) to commonly used antibacterial agents has been updated. 4,975 GNB isolates collected from 22 hospitals across 7 regions of China from 2019 to 2020 were analyzed. Antimicrobial minimum inhibitory concentrations were assessed using broth microdilution, and susceptibility interpretations followed the breakpoints of European Committee on Antimicrobial Susceptibility Testing 2022 or Clinical and Laboratory Standards Institute.

RESULTS

This study affirmed that Escherichia coli (Ec) was the most commonly identified GNB (32.1%) and then Klebsiella pneumoniae (Kp) (25.3%), Pseudomonas aeruginosa (Pa) (13.9%) and Acinetobacter baumannii (10.5%). The detection rates of carbapenem-resistant (CR) Enterobacterales varied across major infection sites, ranging from 10.3% in UTI to 18.9% in RTI. Specifically, the detection rates of CR-Kp and CR-Pa ranged from 16.2% in IAI to 35.8% in UTI and from 16.1% in UTI to 38.0% in RTI, respectively. Extended-spectrum β-lactamases (ESBL)-producing Ec and Kp bacteria exhibited over 91.7% susceptibility to carbapenems and at least 87.8% susceptibility to amikacin and colistin, but showed lower susceptibility to piperacillin/tazobactam (57.5-86.2%), levofloxacin (10.8-39.7%) and aztreonam (15.3-27.6%) across different infection sources. Amikacin showed higher efficacy against CR strains compared to other commonly used antibacterial drugs, with 80.0% susceptibility against CR-Ec and 82.3% susceptibility against CR-Pa, while only 36.3% susceptibility was observed against CR-Kp.

CONCLUSIONS

The study found varying incidences of CR isolates in Chinese hospitals. Treatment options remained limited due to resistance to multiple antibacterial agents. Carbapenems demonstrated effective antimicrobial in vitro activity against ESBL-producing Enterobacterales found in BSI, IAI, UTI and RTI, outperforming broad-spectrum cephalosporins and other β-lactamase inhibitors.

Transfer dynamics of antimicrobial resistance among gram-negative bacteria

Antimicrobial resistance (AMR) in gram-negative bacteria (GNBs) is a significant global health concern, exacerbated by mobile genetic elements (MGEs). This review examines the transfer of antibiotic resistance genes (ARGs) within and between different species of GNB facilitated by MGEs, focusing on the roles of plasmids and phages. The impact of non-antibiotic chemicals, environmental factors affecting ARG transfer frequency, and underlying molecular mechanisms of bacterial resistance evolution are also discussed. Additionally, the study critically assesses the impact of fitness costs and compensatory evolution driven by MGEs in host organisms, shedding light on the transfer frequency of ARGs and host evolution within ecosystems. Overall, this comprehensive review highlights the factors and mechanisms influencing ARG movement among diverse GNB species and underscores the importance of implementing holistic One-Health strategies to effectively address the escalating public health challenges associated with AMR.

Prevalence, Distribution and Antimicrobial Susceptibility of Enterobacteriaceae and Non-Fermenting Gram-Negative Bacilli Isolated From Environmental Samples in a Veterinary Clinical Hospital in Madrid, Spain

Managing infections caused by multidrug-resistant Gram-negative bacilli is a major public health concern, particularly in hospitals where surfaces can act as reservoirs for resistant microorganisms. Identifying these bacteria in hospital environments is crucial for improving healthcare safety. This study aimed to analyse environmental samples from a veterinary hospital to identify prevalent microorganisms and detect antimicrobial resistance patterns. A total of 183 surface samples were collected from 26 areas at the Veterinary Clinical Hospital of Alfonso X el Sabio University in Madrid. The isolated strains were identified, and susceptibility profiles were determined via the disk diffusion method. Clonality analysis was performed using pulsed-field gel electrophoresis. In total, 109 strains were isolated: 76.15% from the Enterobacteriaceae family and 23.85% non-fermenting Gram-negative bacilli. The isolates included Klebsiella, Enterobacter, Escherichia and Pseudomonas species, which could include high-risk clones, given their ability to carry several antimicrobial resistance genes. The equine area had the highest number of isolates (n = 71), accounting for 65% of the total. High resistance indices were observed against at least five of the 16 antibiotics tested, indicating significant multidrug resistance. Clonality analysis suggested potential cross-transmission within the facility. This study sampled hospital surfaces but not personnel or animals, making contamination sources unclear. Without resampling, the effectiveness of cleaning protocols remains uncertain. Results suggest that hospital staff play a key role in bacterial transmission. The lack of specialised preventive measures in veterinary hospitals highlights a need for further research and improvement.

Ceftazidime-avibactam versus other antimicrobial agents for treatment of Multidrug-resistant Pseudomonas aeruginosa: a systematic review and meta-analysis

OBJECTIVES

Multidrug-resistant Pseudomonas aeruginosa (MDR-PA) is a life-threatening infection with limited treatment options. This is the first meta-analysis of recently published data to compare the clinical outcomes of ceftazidime-avibactam (CAZ-AVI) with other antimicrobial agents in treating MDR-PA infections.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase and the Cochrane Library have been systematically reviewed, for publications in the English language, from database inception to July 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies comparing CAZ-AVI outcomes with other antimicrobial agents were included. In-hospital mortality & 30-day mortality were assessed as the main outcomes.

DATA EXTRACTION AND SYNTHESIS

Literature screening, data extraction, and the quality evaluation of studies were conducted by two researchers independently, with disagreements resolved by another researcher. The Newcastle-Ottawa Scale was used to assess the bias risk for the included studies. Review Manager V.5.4 was employed for the meta-analysis.

RESULTS

The meta-analysis included four retrospective studies, enrolling 1934 patients. The CAZ-AVI group demonstrated significantly lower in-hospital mortality (risk ratio (RR) = 0.60, 95% CI:0.37-0.97, I2 = 74%, p = 0.04) in three studies with 1444 patients and lower 30-day mortality, in 438 patients from three studies (RR = 0.54, 95% CI:0.28-1.05, I2 = 67%, p = 0.07). No significant difference in clinical success, microbiological success, length of hospital, and ICU stay was observed.

CONCLUSIONS

This meta-analysis demonstrated that CAZ-AVI treatment significantly lowered in-hospital mortality compared with other antimicrobial agents in MDR-PA infections. However, the analysis only included a few observational studies and high-quality, randomized controlled trials are needed to investigate further the scope of CAZ-AVI in MDR-PA  infections.

Revolutionizing environmental cleanup: the evolution of MOFs as catalysts for pollution remediation

The global problem of ecological safety and public health necessitates, the development of new sustainable ideas for pollution remediation. In recent development, metal-organic frameworks (MOF) are the emerging technology with remarkable potential, which have been employed in environmental remediation. MOFs are networks that are created by the coordination of metals or polyanions with ligands and contain organic components that can be customized. The interesting features of MOFs are a large surface area, tuneable porosity, functional diversity, and high predictability of pollutant adsorption, catalysis, and degradation. It is a solid material that occupies a unique position in the war against environmental pollutants. One of the main benefits of MOFs is that they exhibit selective adsorption of a wide range of pollutants, including heavy metals, organics, greenhouse gases, water and soil. Only particles with the right combination of pore size and chemical composition will achieve this selectivity, derived from the high level of specificity. Besides, they possess high catalytic ability for the removal of pollutants by means of different methods such as photocatalysis, Fenton-like reactions, and oxidative degradation. By generating mobile active sites within the framework of MOFs, we can not only ensure high affinity for pollutants but also effective transformation of toxic chemicals into less harmful or even inert end products. However, the long-term stability of MOFs is becoming more important as eco-friendly parts are replaced with those that can be used repeatedly, and systems based on MOFs that can remove pollutants in more than one way are fabricated. MOFs can reduce waste production, energy consumption as compared to the other removal process. With its endless capacities, MOF technology brings a solution to the environmental cleansing problem, working as a flexible problem solver from one field to another. The investigation of MOF synthesis and principles will allow researchers to fully understand the potential of MOFs in environmental problem solving, making the world a better place for all of us.

Can risk factors and risk scores help predict colonization and infection in multidrug-resistant gram-negative bacteria?

Antimicrobial resistance (AMR) is positioning as one of the most relevant threats to global public health and threatens the effective treatment of an ever-growing number of bacterial infections in various healthcare settings, particularly in acute care and surgical units, as well as in the community. Among multidrug-resistant (MDR) gram-negative bacteria (MDRGNB), Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii require special attention, since they account for most of the mortality associated with bacterial infections and are often MDR. It is clear that there is an important global variation in antibiotic resistance profiles among MDRGNB species. Extended-spectrum β-lactamase-producing Enterobacterales, carbapenem-resistant Enterobacterales, DTR-P. aeruginosa, and MDR-A. baumannii are the focus of this review. Here, we summarize a series of relevant studies on risk factors associated with colonization and infection with these MDRGNB. Likewise, we offer a comparative overview of those studies providing scoring systems to predict the risk of infection with these MDR pathogens, and their pros and cons. Despite the variable accuracy of published risk factors for predicting colonization or infection with MDRGNB, these scores are valuable tools that may help anticipate colonization and infection among those colonized. More importantly, they may help reduce unnecessary use of broad-spectrum antimicrobials and guiding the selection of an optimal treatment.

Co-existence of antibiotic resistance and virulence factors in carbapenem resistant Klebsiella pneumoniae clinical isolates from Alexandria, Egypt

BACKGROUND

The emergence and spread of carbapenem resistance among Enterobacteriaceae, particularly Klebsiella pneumoniae, constitute a serious threat to public health, since carbapenems are the last line of defense in the treatment of life-threatening infections caused by drug-resistant Enterobacteriaceae. The current study investigated the co-existence of different virulence factors and carbapenemases in carbapenem-resistant Klebsiella pneumoniae clinical isolates from Alexandria, Egypt.

RESULTS

Phenotypic characterization of virulence factors indicated that 41.5% of the isolates were strong biofilm producers, while hypermucoviscosity was detected in 14.9% of the isolates. All isolates harbored five or more virulence factor encoding genes. entB, ycfM, mrkD and fimH were detected in all isolates, while only one isolate was negative for ybtS. uge, iutA, rmpA and kpn were detected in 61 (64.8%), 55 (58.5%), 41 (43.6%) and 27 (28.7%) isolates, respectively, while all isolates lacked magA and k2A. Phenotypic detection of carbapenemases was explored by performing CarbaNP and mCIM/eCIM. CarbaNP test showed positive results in 98.9% of the isolates and positive mCIM tests were observed in all isolates, while 68 (72.3%) isolates showed positive eCIM tests. blaNDM was the most prevalent carbapenemase encoding gene (92.5%) followed by the blaOXA-48 (51.1%), while blaKPC was detected in only one (1.06%) isolate. blaVIM, blaIMP and blaGES were not detected in any of the tested isolates.

CONCLUSIONS

The widespread of carbapenem-resistant Klebsiella pneumoniae represents a major problem in health care settings. A significant association between certain virulence factors and carbapenemase-encoding genes was observed. Antibiotic stewardship programs and infection control policies should be effectively implemented especially in hospitals to limit the spread of such highly virulent pathogens.

Temporal Shifts in Etiological Agents and Antibiotic Resistance Patterns of Biliary Tract Infections in Sichuan Province, China (2017-2023)

Purpose

We analyzed the pathogenic bacteria and antibiotic resistance distributions in patients with biliary tract infections (BTI) using samples from the Antimicrobial Resistant Investigation Network of Sichuan Province (ARINSP) to promote the rational use of antibiotics to reduce multidrug resistance.

Patients and Methods

Participating hospitals identified isolates between 2017 and 2023 and conducted antimicrobial susceptibility tests. Isolated bacteria were identified and tested for drug sensitivity using MOLDI-TOF mass spectrometry system, VITEK automated drug sensitivity system and paper diffusion method, and the results were interpreted with reference to CLSI M100 30th edition standards. WHONET 5.6 was used to analyze the results.

Results

In total, 25,573 bacterial isolates were collected; 18,134 were Gram-negative (70.9%). The top five most frequently isolated bacteria were Escherichia coli (8,181/25,573; 32.0%), Klebsiella pneumoniae (3,247/25,573; 12.7%), Enterococcus faecium (2,331/25,573; 9.1%), Enterococcus faecalis (1,714/25,573; 6.7%), and Enterobacter cloacae (1,429/25,573; 5.6%). E. coli and E. faecalis slowly declined over time, while K. pneumoniae slowly increased; E. faecium frequency was stable; E. coli resistance to ampicillin was the highest among all antibiotics tested; resistance rates decreased with the addition of sulbactam. K. pneumoniae resistance to aztreonam, imipenem, meropenem, ertapenem, and chloramphenicol remained low. E. cloacae was highly resistant to cephalosporins, especially cefoxitin and cefazolin. E. faecalis' resistance to teicoplanin remained low, decreasing from 6.9% in 2017 to 0.0% in 2019 before stabilizing.

Conclusion

The most frequently isolated bacteria from patients with BTIs were Enterobacteriaceae, including E. coli and K. pneumoniae, followed by E. faecium and E. faecalis. Isolates exhibited high resistance to routinely used antibiotics (cephalosporins) and were highly sensitive to tigecycline, carbapenem, amikacin, and vancomycin. The results guide the rational use and continual revision of antibiotic regimens for BTIs to reduce antibiotic resistance.

Characterization of Antibiotic Resistance Profiles in the Oral Microbiota of the Pakistani Population

Background The oral microbiota's resistance to antibiotics presents a serious threat to world health, especially in developing nations where misuse of antibiotics is common. Objective The objective of this study was to characterize the antibiotic resistance profiles in the oral microbiota of Pakistani adults. Methodology The Department of Microbiology at Akhtar Saeed Medical and Dental College in Lahore, Pakistan, carried out a cross-sectional study from January 2022 to December 2022. Oral swabs were collected from 240 adults (aged 18 and older) who had not used antibiotics in the past three months. The disk diffusion method was used for both antibiotic susceptibility testing and bacterial cultures. Descriptive statistics and logistic regression analysis were conducted using IBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York, United States) to examine associations within the demographic data. Results The study examined 240 participants, comprising 133 students (55.42%), 64 professionals (26.67%), and 43 individuals in other occupations (17.92%). Of the participants, 128 were male (53.33%) and 112 were female (46.67%). With 81 isolates (33.75%), Streptococcus mutans was the most common species of bacterium, followed by Staphylococcus aureus with 69 isolates (28.75%). The majority of cases (n = 72; 30.00%) were resistant to penicillin, followed by erythromycin (22.50%) in 54 instances and tetracycline (19.58%) in 47 cases. Age group (50 years and above; β = 0.120, OR = 1.128, p = 0.017), penicillin resistance (β = 0.150, OR = 1.162, p = 0.001), erythromycin resistance (β = 0.120, OR = 1.128, p = 0.013), and ciprofloxacin resistance (β = 0.130, OR = 1.139, p = 0.014) were all significantly associated with the results of the regression analysis. Additionally, resistance was positively associated with the occupation "student" (β = 0.110, OR = 1.116, p = 0.047). Conclusion The high levels of antibiotic resistance observed, particularly in older age groups and certain occupations, underscore the urgent need for enhanced antibiotic stewardship and regulatory measures in Pakistan.

Nanomedicine: Patuletin-conjugated with zinc oxide exhibit potent effects against Gram-negative and Gram-positive bacterial pathogens

With the emergence of drug-resistance, there is a need for novel anti-bacterials or to enhance the efficacy of existing drugs. In this study, Patuletin (PA), a flavanoid was loaded onto Gallic acid modified Zinc oxide nanoparticles (PA-GA-ZnO), and evaluated for antibacterial properties against Gram-positive (Bacillus cereus and Streptococcus pneumoniae) and Gram-negative (Samonella enterica and Escherichia coli) bacteria. Characterization of PA, GA-ZnO and PA-GA-ZnO' nanoparticles was accomplished utilizing fourier-transform infrared spectroscopy, efficiency of drug entrapment, polydispersity index, zeta potential, size, and surface morphology analysis through atomic force microscopy. Using bactericidal assays, the results revealed that ZnO conjugation displayed remarkable effects and enhanced Patuletin's effects against both Gram-positive and Gram-negative bacteria, with the minimum inhibitory concentration observed at micromolar concentrations. Cytopathogenicity assays exhibited that the drug-nanoconjugates reduced bacterial-mediated human cell death with minimal side effects to human cells. When tested alone, drug-nanoconjugates tested in this study showed limited toxic effects against human cells in vitro. These are promising findings, but future work is needed to understand the molecular mechanisms of effects of drug-nanoconjugates against bacterial pathogens, in addition to in vivo testing to determine their translational value. This study suggests that Patuletin-loaded nano-formulation (PA-GA-ZnO) may be implicated in a multi-target mechanism that affects both Gram-positive and Gram-negative pathogen cell structures, however this needs to be ascertained in future work.

Characterization, Antibiotic Susceptibility, and Clonal Analysis of Carbapenem-Resistant Klebsiella pneumoniae From Different Clinical Cases

INTRODUCTION

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is recognized for its great ability to resist prescription drugs and its association with severe infections in humans.

OBJECTIVES

This study was designed to evaluate the characteristic resistance spectrum, to characterize the implicated carbapenem-resistant genes (CRGs), and to determine the extent of genetic diversity among Klebsiella pneumoniae isolates from human clinical cases in Duhok province.  Methodology: The VITEK-2 system was used to investigate the phenotypic antibiotic susceptibility of 23 K. pneumoniae isolated from distinct human clinical situations, multiplex PCR was used to assign the key common carbapenem-resistant genes (IMP, OXA48-like, bla-NDM, and KPC) in phenotypically carbapenem-resistant isolates, and the Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) assay was utilized to ascertain the clonal associations among those isolates.

RESULTS

Phenotypic resistance analysis revealed high resistance rates to various antibiotics, with all isolates exhibiting multidrug resistance (MDR). Coronavirus disease 2019 (COVID-19) patient isolates demonstrated significantly higher resistance compared to other sources. In addition, all isolates showed complete phenotypic resistance to carbapenems, PCR screening for CRGs identified blaOXA-48 as the predominant gene, present in all isolates. Genetic fingerprinting revealed diverse genotypes, with COVID-19 patient isolates exhibiting high similarity, contrasting with maximum diversity in non-COVID-19 clinical isolates.

An Overview of the Recent Advances in Antimicrobial Resistance

Antimicrobial resistance (AMR), frequently considered a major global public health threat, requires a comprehensive understanding of its emergence, mechanisms, advances, and implications. AMR's epidemiological landscape is characterized by its widespread prevalence and constantly evolving patterns, with multidrug-resistant organisms (MDROs) creating new challenges every day. The most common mechanisms underlying AMR (i.e., genetic mutations, horizontal gene transfer, and selective pressure) contribute to the emergence and dissemination of new resistant strains. Therefore, mitigation strategies (e.g., antibiotic stewardship programs-ASPs-and infection prevention and control strategies-IPCs) emphasize the importance of responsible antimicrobial use and surveillance. A One Health approach (i.e., the interconnectedness of human, animal, and environmental health) highlights the necessity for interdisciplinary collaboration and holistic strategies in combating AMR. Advancements in novel therapeutics (e.g., alternative antimicrobial agents and vaccines) offer promising avenues in addressing AMR challenges. Policy interventions at the international and national levels also promote ASPs aiming to regulate antimicrobial use. Despite all of the observed progress, AMR remains a pressing concern, demanding sustained efforts to address emerging threats and promote antimicrobial sustainability. Future research must prioritize innovative approaches and address the complex socioecological dynamics underlying AMR. This manuscript is a comprehensive resource for researchers, policymakers, and healthcare professionals seeking to navigate the complex AMR landscape and develop effective strategies for its mitigation.

BWC0977, a broad-spectrum antibacterial clinical candidate to treat multidrug resistant infections

The global crisis of antimicrobial resistance (AMR) necessitates the development of broad-spectrum antibacterial drugs effective against multi-drug resistant (MDR) pathogens. BWC0977, a Novel Bacterial Topoisomerase Inhibitor (NBTI) selectively inhibits bacterial DNA replication via inhibition of DNA gyrase and topoisomerase IV. BWC0977 exhibited a minimum inhibitory concentration (MIC90) of 0.03-2 µg/mL against a global panel of MDR Gram-negative bacteria including Enterobacterales and non-fermenters, Gram-positive bacteria, anaerobes and biothreat pathogens. BWC0977 retains activity against isolates resistant to fluoroquinolones (FQs), carbapenems and colistin and demonstrates efficacy against multiple pathogens in two rodent species with significantly higher drug levels in the epithelial lining fluid of infected lungs. In healthy volunteers, single-ascending doses of BWC0977 administered intravenously ( https://clinicaltrials.gov/study/NCT05088421 ) was found to be safe, well tolerated (primary endpoint) and achieved dose-proportional exposures (secondary endpoint) consistent with modelled data from preclinical studies. Here, we show that BWC0977 has the potential to treat a range of critical-care infections including MDR bacterial pneumonias.

Convergent synthesis of the pentasaccharide repeating unit corresponding to the cell wall O-polysaccharide of Salmonella milwaukee (group U) O:43 strain

Synthesis of the pentasaccharide repeating unit of the cell O-polysaccharide produced by Salmonella milwaukee O:43 strain (group U) has been achieved in very good yield adopting a convergent stereoselective [3 + 2] block glycosylation strategy. Thioglycosides and glycosyl trichloroacetimidate derivative were used as glycosyl donors in the presence of a combination of N-iodosuccinimide (NIS) and trimethylsilyl trifluoromethanesulfonate (TMSOTf) as thiophilic activator and TMSOTf as trichloroacetimidate activator respectively. The stereochemical outcome of all glycosylation reactions was excellent.

Ceftazidime-Avibactam as a Salvage Treatment for Severely Infected Immunosuppressed Children

Background

Multidrug-resistant Gram-negative bacteria (MDR-GNB) are becoming increasingly common around the world, with carbapenems frequently serving as a last resort but being threatened by the growing incidence of carbapenemase-producing bacteria. Ceftazidime-avibactam (CAZ/AVI) is a potential agent against MDR-GNB but with limited clinical experience, particularly in critically ill immunosuppressed children.

Methods

This study analyzed the use of CAZ/AVI as salvage treatment in severely infected immunosuppressed children from September 2019 to July 2022. Patients with confirmed GNB infection who received CAZ/AVI were matched with patients who received other antibiotics.

Results

Twenty-five critically ill immunosuppressed children treated with CAZ/AVI were included. The majority had hematologic diseases. All patients presented with sepsis in all 30 courses. Septic shock presented in 36.7% of these courses. The primary sites of infection included bloodstream infection (20.0%), skin and skin structure infection (20.0%), intra-abdominal infection (13.3%) and hospital-acquired pneumonia (10.0%). Twelve of the 25 (48.0%) patients had positive microbiological cultures, mainly Pseudomonas aeruginosa and Klebsiella pneumoniae, including 5 carbapenem-resistant GNB-infected cases. Fifteen (50.0%) courses presented clinical improvement. For the initial course of each patient, the clinical response rate of the GNB recovered group was significantly higher than that of the group without GNB recovery (66.7% vs 23.1%, P = 0.047). The 14-day and 30-day mortality rates were 24.0% and 28.0%, respectively, which were significantly correlated with the absence of GNB recovery (P = 0.004 and 0.024, respectively) and hospital-acquired pneumonia as the primary site of infection (P = 0.001 and 0.006, respectively). There was no significant difference in major outcomes between patients who received CAZ/AVI and matched patients who received other antibiotics.

Conclusion

CAZ/AVI could be considered a salvage strategy for immunosuppressed children with confirmed GNB infection. Caution should be taken when CAZ/AVI is applied to these patients in the absence of GNB recovery.

Prevalence and Phenotypic Characterization of Antibiotic-resistant Enterococcus Species Isolated from Chicken Faecal Samples in Accra, Ghana

Background

Enterococci are bacteria found naturally in the gastrointestinal tract of both chickens and humans, serving as a commensal bacterium. These opportunistic pathogens are recognized for their involvement in human diseases like urinary tract infections (UTIs), endocarditis, and sepsis. Infection sources encompass food, hospital environments, and animals, particularly chickens. Their increasing resistance to multiple drugs poses a growing concern for public healthThis study aimed to isolate the enterococcus species and to determine their antibiotic susceptibility profiles.

Method

Swab samples of gut content from poultry in specific slaughterhouses located within selected markets in Accra were collected, cultured on MacConkey agar No.2, and incubated overnight for growth. Colonies suspected to be Enterococcus species were subjected to biochemical testing, and confirmed colonies underwent antibiotic testing against commonly used medications for bacterial infections. The Kirby-Bauer disk diffusion method was used to assess the antibiotic susceptibility of the recovered isolates.

Results

Among the 160 samples examined, 97 (61%) were found to be contaminated with Enterococcus species. Each of the isolates displayed resistance to a minimum of three antibiotic classes tested in the study. Notably, high levels of resistance were observed for specific antibiotics, including penicillin (91.75%), vancomycin (87.63%), and tetracycline (80.41).

Conclusion

The findings of this study revealed a high prevalence of multi-drug resistant Enterococcus species isolated from chicken rectal swab samples collected from three selected markets in Accra, Ghana. All the isolates exhibited resistance to at least three classes of antibiotics tested.

Efficacy of Zoliflodacin, a Spiropyrimidinetrione Antibiotic, Against Gram-Negative Pathogens

Zoliflodacin is a spiropyrimidinetrione antibiotic that acts by binding to the GyrB part of the DNA gyrase enzyme in bacteria. Its effectiveness for the treatment of Neisseria gonorrhoeae infections has been investigated extensively. Since antibiotic resistance has been reached an alarming rate worldwide, researches on new antimicrobials are considered a priority, especially in the treatment of multidrug-resistant Gram-negative bacteria, such as Klebsiella pneumonia. The aim of this study is to test and compare the effectiveness of zoliflodacin with some traditional antibiotics which are frequently preferred in the treatment of Gram-negative pathogens, primarily K. pneumonia. Additionally, its ability to prevent biofilm formation has also been determined. The minimum inhibitory concentration (MIC) values of zoliflodacin along with levofloxacin, meropenem, gentamicin, ampicillin/sulbactam and ceftazidime/avibactam were evaluated by broth microdilution method against 15 Gram-negative clinical isolates and three standard strains. Also, the synergism potential of zoliflodacin with other antibiotics was evaluated by the checkerboard method against standard strains of K. pneumonia, Pseudomonas aeruginosa, and Acinetobacter baumannii. In addition, the inhibitory effects of zoliflodacin on biofilm formation of standard strains were determined. Zoliflodacin MICs were found to be in the range of 2-64 µg/mL, and its combination with meropenem and ampicillin/sulbactam was found to be synergistic, especially against A. baumannii. Zoliflodacin significantly inhibited A. baumannii biofilm at sub-MIC values. These results indicated that zoliflodacin can be considered as an alternative against infections of Gram-negative pathogens, alone or in combination.

Co-Infection of SARS-CoV-2 and Klebsiella pneumoniae: A Systematic Review and Meta-Analysis

The study aimed to assess the prevalence of COVID-19 and Klebsiella spp. coinfection across continents. Conducted following PRISMA guidelines, a systematic review utilized PubMed, Embase, SCOPUS, ScienceDirect, and Web of Science databases, searching for literature in English published from December 2019 to December 2022, using specific Health Sciences descriptors. A total of 408 records were identified, but only 50 were eligible, and of these, only 33 were included. Thirty-three references were analyzed to evaluate the correlation between COVID-19 and Klebsiella spp. infections. The tabulated data represented a sample group of 8741 coinfected patients. The findings revealed notable disparities in co-infection rates across continents. In Asia, 23% of individuals were infected with Klebsiella pneumoniae, while in Europe, the proportion of co-infected patients stood at 15%. Strikingly, on the African continent, 43% were found to be infected with Klebsiella pneumoniae, highlighting significant regional variations. Overall, the proportion of Klebsiella pneumoniae co-infections among COVID-positive individuals were determined to be 19%. Particularly concerning was the observation that 1 in 6 ICU coinfections was attributed to Klebsiella pneumoniae, indicating its substantial impact on patient outcomes and healthcare burden. The study underscores the alarming prevalence of co-infection between COVID-19 and Klebsiella pneumoniae, potentially exacerbating the clinical severity of patients and posing challenges to treatment strategies. These findings emphasize the importance of vigilant surveillance and targeted interventions to mitigate the adverse effects of bacterial coinfections in the context of the COVID-19 pandemic.

Membrane Permeability Dominates over Electrostatic Interactions in Dictating Drug Transport in Osmotically Shocked Escherichia coli

To combat surging multidrug-resistant Gram-negative bacterial infections, better strategies to improve the efficacy of existing drugs are critical. Because the dual membrane cell envelope is the first line of defense for these bacteria, it is crucial to understand the permeation properties of the drugs through it. Our recent study shows that isosmotic conditions prevent drug permeation inside Gram-negative bacteria, Escherichia coli, while hypoosmotic stress enhances the process. Here, we unravel the reason behind such differential drug penetration. Specifically, we dissect the roles of electrostatic screening and low membrane permeability in the penetration failure of drugs under osmotically balanced conditions. We compare the transport of a quaternary ammonium compound malachite green in the presence of an electrolyte (NaCl) and a wide variety of commonly used organic osmolytes, e.g., sucrose, proline, glycerol, sorbitol, and urea. These osmolytes of different membrane permeability (i.e., nonpermeable sucrose and NaCl, freely permeable urea and glycerol, and partially permeable proline and sorbitol) clarify the role of osmotic stress in cell envelope permeability. The results showcase that under balanced osmotic conditions, drug molecules fail to penetrate inside E. coli cells because of low membrane permeabilities and not because of electrostatic screening imposed by the osmolytes. Contribution of the electrostatic interactions, however, cannot be completely overruled as at osmotically imbalanced conditions, drug transport across the bacterial subcellular compartments is found to be dependent on the osmolytes used.

Brucine Sulfate, a Novel Bacteriostatic Agent in 3D Printed Bone Scaffold Systems

Bacterial infection is a common complication in bone defect surgery, in which infection by clinically resistant bacteria has been a challenge for the medical community. Given this emerging problem, the discovery of novel natural-type inhibitors of drug-resistant bacteria has become imperative. Brucine, present in the traditional Chinese herb Strychnine semen, is reported to exert analgesic and anti-inflammatory effects. Brucine's clinical application was limited because of its water solubility. We extracted high-purity BS by employing reflux extraction and crystallization, greatly improved its solubility, and evaluated its antimicrobial activity against E. coli and S. aureus. Importantly, we found that BS inhibited the drug-resistant strains significantly better than standard strains and achieved sterilization by disrupting the bacterial cell wall. Considering the safety concerns associated with the narrow therapeutic window of BS, a 3D BS-PLLA/PGA bone scaffold system was constructed with SLS technology and tested for its performance, bacteriostatic behaviors, and biocompatibility. The results have shown that the drug-loaded bone scaffolds had not only long-term, slow-controlled release with good cytocompatibility but also demonstrated significant antimicrobial activity in antimicrobial testing. The above results indicated that BS may be a potential drug candidate for the treatment of antibiotic-resistant bacterial infections and that scaffolds with enhanced antibacterial activity and mechanical properties may have potential applications in bone tissue engineering.

Unveiling the landscape of resistance against high priority critically important antimicrobials in food-producing animals across Africa: A scoping review

The rapid population growth in Africa is associated with an increasing demand for livestock products which in turn can lead to antimicrobial use. Antimicrobial usage in animals contributes to the emergence and selection of resistant bacteria which constitutes a serious public health threat. This study aims to review and summarize the available information on highest priority critically important antimicrobials (HPCIAs) resistance in livestock production in Africa. This work will help to inform future policies for controlling antimicrobial resistance (AMR) in the food production chain. A scoping review was conducted according to the Cochrane handbook and following PRISMA 2020 guidelines for reporting. Primary research studies published after 1999 and reporting resistance of Escherichia coli, Enterococcus spp, Staphylococcus aureus, Salmonella spp, and Campylobacter spp to HPCIAs in poultry, cattle, pigs, goats, and sheep in Africa were searched in four databases. A total of 312 articles were included in the review. The majority of the studies (40.7) were conducted in North African countries. More than 49.0% of included studies involved poultry and 26.2% cattle. Cephalosporins and quinolones were the most studied antimicrobial classes. Of the bacteria investigated in the current review, E. coli (41.7%) and Salmonella spp (24.9%) represented the most commonly studied. High levels of resistance against erythromycin in E. coli were found in poultry (MR 96.1%, IQR 83.3-100.0%), cattle (MR 85.7%, IQR 69.2-100.0%), and pigs (MR 94.0%, IQR 86.2-94.0%). In sheep, a high level of resistance was observed in E. coli against nalidixic acid (MR 87.5%, IQR 81.3-93.8%). In goats, the low level of sensibility was noted in S. aureus against streptomycin (MR 86.8%, IQR 19.4-99.0%). The study provides valuable information on HPCIAs resistance in livestock production in Africa and highlights the need for further research and policies to address the public health risk of AMR. This will likely require an investment in diagnostic infrastructure across the continent. Awareness on the harmful impact of AMR in African countries is a requirement to produce more effective and sustainable measures to curb AMR.

Vesicle protrusion induced by antimicrobial peptides suggests common carpet mechanism for short antimicrobial peptides

Short-cationic alpha-helical antimicrobial peptides (SCHAMPs) are promising candidates to combat the growing global threat of antimicrobial resistance. They are short-sequenced, selective against bacteria, and have rapid action by destroying membranes. A full understanding of their mechanism of action will provide key information to design more potent and selective SCHAMPs. Molecular Dynamics (MD) simulations are invaluable tools that provide detailed insights into the peptide-membrane interaction at the atomic- and meso-scale level. We use atomistic and coarse-grained MD to look into the exact steps that four promising SCHAMPs-BP100, Decoralin, Neurokinin-1, and Temporin L-take when they interact with membranes. Following experimental set-ups, we explored the effects of SCHAMPs on anionic membranes and vesicles at multiple peptide concentrations. Our results showed all four peptides shared similar binding steps, initially binding to the membrane through electrostatic interactions and then flipping on their axes, dehydrating, and inserting their hydrophobic moieties into the membrane core. At higher concentrations, fully alpha-helical peptides induced membrane budding and protrusions. Our results suggest the carpet mode of action is fit for the description of SCHAMPs lysis activity and discuss the importance of large hydrophobic residues in SCHAMPs design and activity.

Pharmacological Potential of Kaempferol, a Flavonoid in the Management of Pathogenesis via Modulation of Inflammation and Other Biological Activities

Natural products and their bioactive compounds have been used for centuries to prevent and treat numerous diseases. Kaempferol, a flavonoid found in vegetables, fruits, and spices, is recognized for its various beneficial properties, including its antioxidant and anti-inflammatory potential. This molecule has been identified as a potential means of managing different pathogenesis due to its capability to manage various biological activities. Moreover, this compound has a wide range of health-promoting benefits, such as cardioprotective, neuroprotective, hepatoprotective, and anti-diabetic, and has a role in maintaining eye, skin, and respiratory system health. Furthermore, it can also inhibit tumor growth and modulate various cell-signaling pathways. In vivo and in vitro studies have demonstrated that this compound has been shown to increase efficacy when combined with other natural products or drugs. In addition, kaempferol-based nano-formulations are more effective than kaempferol treatment alone. This review aims to provide detailed information about the sources of this compound, its bioavailability, and its role in various pathogenesis. Although there is promising evidence for its ability to manage diseases, it is crucial to conduct further investigations to know its toxicity, safety aspects, and mechanism of action in health management.

Comparison of pharmacokinetics software for therapeutic drug monitoring of piperacillin in patients with severe infections

OBJECTIVE

To evaluate the predictive performance of population pharmacokinetic models for piperacillin (PIP) available in the software MwPharm, TDMx and ID-ODs for initial dosing selection and therapeutic drug monitoring (TDM) purposes.

METHODS

This is a prospective observational study in adult patients with severe infections receiving PIP treatment. Plasma concentrations were quantified by ultra-high performance liquid chromatography coupled to tandem mass spectrometry. The differences between predicted and observed PIP concentrations were evaluated with Bland-Altman plots; additionally, the relative and absolute bias and precision of the models were determined.

RESULTS

A total of 145 PIP plasma concentrations from 42 patients were analysed. For population prediction, MwPharm showed the best predictive performance with a mean relative difference of 34.68% (95% CI -197% to 266%) and a root mean square error (RMSE) of 60.42 µg/mL; meanwhile TDMx and ID-ODs under-predicted PIP concentrations. For individual prediction, the TDMx model was found to be the most precise with a mean relative difference of 7.61% (95% CI -57.63 to 72.86%), and RMSE of 17.86 µg/mL.

CONCLUSION

Current software for TDM is a valuable tool, but it may also include different population pharmacokinetic models in patients with severe infections, and should be evaluated before performing a model-based TDM in clinical practice. Considering the heterogeneous characteristics of patients with severe infections, this study demonstrates the need for therapy personalisation for PIP to improve pharmacokinetic/pharmacodynamic target attainment.

Inflammaging in Multidrug-Resistant Sepsis of Geriatric ICU Patients and Healthcare Challenges

Multidrug-resistant sepsis (MDR) is a pressing concern in intensive care unit (ICU) settings, specifically among geriatric patients who experience age-related immune system changes and comorbidities. The aim of this review is to explore the clinical impact of MDR sepsis in geriatric ICU patients and shed light on healthcare challenges associated with its management. We conducted a comprehensive literature search using the National Center for Biotechnology Information (NCBI) and Google Scholar search engines. Our search incorporated keywords such as "multidrug-resistant sepsis" OR "MDR sepsis", "geriatric ICU patients" OR "elderly ICU patients", and "complications", "healthcare burdens", "diagnostic challenges", and "healthcare challenges" associated with MDR sepsis in "ICU patients" and "geriatric/elderly ICU patients". This review explores the specific risk factors contributing to MDR sepsis, the complexities of diagnostic challenges, and the healthcare burden faced by elderly ICU patients. Notably, the elderly population bears a higher burden of MDR sepsis (57.5%), influenced by various factors, including comorbidities, immunosuppression, age-related immune changes, and resource-limited ICU settings. Furthermore, sepsis imposes a significant economic burden on healthcare systems, with annual costs exceeding $27 billion in the USA. These findings underscore the urgency of addressing MDR sepsis in geriatric ICU patients and the need for tailored interventions to improve outcomes and reduce healthcare costs.

Next-generation microbiological testing in intraabdominal infections with PCR technology

PURPOSE

Intraabdominal infections (IAI) are increasing worldwide and are a major contributor to morbidity and mortality. Among IAI, the number of multi-drug resistant organisms (MDRO) is increasing globally. We tested the Unyvero A50® for intraabdominal infections, compared the detected microorganisms and antibiotic resistance, and compared the results with those of routine microbiology.

METHODS

We prospectively compared samples obtained from surgical patients using PCR-based Unyvero IAI cartridges against routine microbiology for the detection of microorganisms. Additionally, we identified clinical parameters that correlated with the microbiological findings. Data were analyzed using the t-test and Mann-Whitney U test.

RESULTS

Sixty-two samples were analyzed. The PCR system identified more microorganisms, mostly Bacteroides species, Escherichia coli, and Enterococcus spp. For bacterial resistance, the PCR system results were fully concordant with those of routine microbiology, resulting in a sensitivity, specificity, and positive and negative predictive value (PPV, NPV) of 100%. The sensitivity, specificity, PPV, and NPV for the detection of microorganisms were 74%, 58%, 60%, and 72%, respectively. CRP levels were significantly higher in patients with detectable microorganisms. We identified more microorganisms and bacterial resistance in hospital-acquired intra-abdominal infections by using the PCR system.

DISCUSSION

IAI warrants early identification of the microorganisms involved and their resistance to allow for adequate antibiotic therapy. PCR systems enable physicians to rapidly adjust their antibiotic treatment. Conventional microbiological culture and testing remain essential for determining the minimal growth inhibition concentrations for antibiotic therapy.

Efficacy of Short-Course Antibiotic Therapy for Acute Cholangitis With Positive Blood Cultures: A Retrospective Study

BACKGROUND

Short-term treatment of acute cholangitis is sufficient for cure compared with the standard treatment duration. Whether this short-course antimicrobial therapy is effective in patients with acute cholangitis with positive blood cultures has not been fully investigated. This study assessed whether patients with acute cholangitis could achieve successful outcomes with a three-day or shorter antimicrobial treatment period, even with a positive blood culture.

METHODS

This single-center retrospective study involved patients with acute cholangitis, defined according to the Tokyo Guidelines 2018 for any cause, who underwent successful biliary drainage and completed a seven-day or shorter antimicrobial treatment. Patients were categorized into six groups based on the duration of antibiotic use (short or standard) after endoscopic retrograde cholangiopancreatography and blood culture findings (positive, negative, or no collection). The primary outcome was the clinical cure rate, defined as no initial presenting symptoms by day 14 after biliary drainage and no recurrence or death by day 30. Secondary outcomes included a three-month recurrence rate and length of hospital stay.

RESULTS

In total, 389 cases were selected, and 27 patients (6.9%) undergoing short-course therapy tested positive for blood culture. The clinical cure rate (n=25, 92.6%) in this group was comparable to that in the other groups. For the three-month recurrence rate (n=1, 3.7%) and median hospital stay (six days), this group's outcomes were either better or similar to those of the other groups.

CONCLUSIONS

For cases of successful drainage in acute cholangitis, even with positive blood cultures, short-term antibiotic therapy may be appropriate.

Epidemiology, Clinical, and Microbiological Characteristics of Multidrug-Resistant Gram-Negative Bacteremia in Qatar

Antimicrobial resistance is a global healthcare threat with significant clinical and economic consequences peaking at secondary and tertiary care hospitals where multidrug-resistant Gram-negative bacteria (MDR GNB) lead to poor outcomes. A prospective study was conducted between January and December 2019 for all invasive bloodstream infections (BSIs) secondary to MDR GNB in Qatar identified during routine microbiological service to examine their clinical, microbiological, and genomic characteristics. Out of 3238 episodes of GNB BSIs, the prevalence of MDR GNB was 13% (429/3238). The predominant MDR pathogens were Escherichia coli (62.7%), Klebsiella pneumoniae (20.4%), Salmonella species (6.6%), and Pseudomonas aeruginosa (5.3%), while out of 245 clinically evaluated patients, the majority were adult males, with the elderly constituting almost one-third of the cohort and with highest observed risk for prolonged hospital stays. The risk factors identified included multiple comorbidities, recent healthcare contact, previous antimicrobial therapy, and admission to critical care. The in-hospital mortality rate was recorded at 25.7%, associated with multiple comorbidities, admission to critical care, and the acquisition of MDR Pseudomonas aeruginosa. Resistant pathogens demonstrated high levels of antimicrobial resistance but noticeable susceptibility to amikacin and carbapenems. Genomic analysis revealed that Escherichia coli ST131 and Salmonella enterica ST1 were the predominant clones not observed with other pathogens.

Design, semi-synthesis of soft coral-derived Aspergillus sp. secondary metabolite geodin derivatives and their antibacterial activities

A series of novel ester derivatives 2 - 7, of natural product geodin 1, isolated from the soft coral-derived fungus Aspergillus sp., were designed and semi-synthesised through one step reaction with high yield. Compound 5 showed strong antifouling inhibitory activities with MIC of 4.80 μM while compound 4 showed selective inhibitory activities with MICs values 8.59 μM against Aeromonas salmonicida and Pseudomonas aeruginosa (Sea-Nine 211, MIC = 0.27 μM). Compounds 3, 4 and 6 showed potent anti-pathogenic inhibitory activities with MICs of 2.29 μM, 4.29 μM and 4.56 μM respectively against Staphylococcus aureus (Ciprofloxacin, MIC = 0.156 μM). Compound 2 showed weak inhibitory activity against A. salmonicida with MIC 18.75 μM (Sea-Nine 211, MIC = 0.27 μM) and with MICs 9.38 μM against S. aureus (ciprofloxacin, MIC = 0.156 μM). However, compound 7 showed very low antibacterial activities with MIC = >20 μM. The preliminary structure-activity relationships of compounds 2 - 7 further prove that the modification of 4-OH group of natural product geodin 1 improves the antibacterial activities such as antifouling and anti-pathogenic activities.

Characterization of ES10 lytic bacteriophage isolated from hospital waste against multidrug-resistant uropathogenic E. coli

Escherichia coli is the major causative agent of urinary tract infections worldwide and the emergence of multi-drug resistant determinants among clinical isolates necessitates the development of novel therapeutic agents. Lytic bacteriophages efficiently kill specific bacteria and seems promising approach in controlling infections caused by multi-drug resistant pathogens. This study aimed the isolation and detailed characterization of lytic bacteriophage designated as ES10 capable of lysing multidrug-resistant uropathogenic E. coli. ES10 had icosahedral head and non-contractile tail and genome size was 48,315 base pairs long encoding 74 proteins. Antibiotics resistance, virulence and lysogenic cycle associated genes were not found in ES10 phage genome. Morphological and whole genome analysis of ES10 phage showed that ES10 is the member of Drexlerviridae. Latent time of ES10 was 30 min, burst size was 90, and optimal multiplicity of infection was 1. ES10 was stable in human blood and subsequently caused 99.34% reduction of host bacteria. Calcium chloride shortened the adsorption time and latency period of ES10 and significantly inhibited biofilm formation of host bacteria. ES10 caused 99.84% reduction of host bacteria from contaminated fomites. ES10 phage possesses potential to be utilized in standard phage therapy.

Carbon Dot Based Carbon Nanoparticles as Potent Antimicrobial, Antiviral, and Anticancer Agents

Antimicrobial and anticancer drugs are widely used due to increasing widespread infectious diseases caused by microorganisms such as bacterial, fungal, viral agents, or cancer cells, which are one of the major causes of mortality globally. Nevertheless, several microorganisms developed resistance to antibiotics as a result of genetic changes that have occurred over an extended period. Carbon-based materials, particularly carbon dots (C-dots), are potential candidates for antibacterial and anticancer nanomaterials due to their low toxicity, ease of synthesis and functionalization, high dispersibility in aqueous conditions, and promising biocompatibility. In this Review, the content is divided into four sections. The first section concentrates on C-dot structures, surface functionalization, and morphology. Following that, we summarize C-dot classifications and preparation methods such as arc discharge, laser ablation, electrochemical oxidation, and so on. The antimicrobial applications of C-dots as antibacterial, antifungal, and antiviral agents both in vivo and in vitro are discussed. Finally, we thoroughly examined the anticancer activity displayed by C-dots.

A FtsZ Inhibitor That Can Utilize Siderophore-Ferric Iron Uptake Transporter Systems for Activity against Gram-Negative Bacterial Pathogens

The global threat of multidrug-resistant Gram-negative bacterial pathogens necessitates the development of new and effective antibiotics. FtsZ is an essential and highly conserved cytoskeletal protein that is an appealing antibacterial target for new antimicrobial therapeutics. However, the effectiveness of FtsZ inhibitors against Gram-negative species has been limited due in part to poor intracellular accumulation. To address this limitation, we have designed a FtsZ inhibitor (RUP4) that incorporates a chlorocatechol siderophore functionality that can chelate ferric iron (Fe3+) and utilizes endogenous siderophore uptake pathways to facilitate entry into Gram-negative pathogens. We show that RUP4 is active against both Klebsiella pneumoniae and Acinetobacter baumannii, with this activity being dependent on direct Fe3+ chelation and enhanced under Fe3+-limiting conditions. Genetic deletion studies in K. pneumoniae reveal that RUP4 gains entry through the FepA and CirA outer membrane transporters and the FhuBC inner membrane transporter. We also show that RUP4 exhibits bactericidal synergy against K. pneumoniae when combined with select antibiotics, with the strongest synergy observed with PBP2-targeting β-lactams or MreB inhibitors. In the aggregate, our studies indicate that incorporation of Fe3+-chelating moieties into FtsZ inhibitors is an appealing design strategy for enhancing activity against Gram-negative pathogens of global clinical significance.

Timing and clinical risk factors for early acquisition of gut pathogen colonization with multidrug resistant organisms in the intensive care unit

BACKGROUND

Microbiome restitution therapies are being developed to prevent gut pathogen colonization among patients in the intensive care unit (ICU) and in other select populations. If preventive therapies are to be effective, they must be administered prior to pathogen acquisition. The timing and risk factors for early acquisition of gut pathogen colonization (within 72 h) are currently unknown and could be helpful to guide ICU trial design.

METHODS

This was a prospective cohort study. Patients in the ICU had deep rectal swabs performed within 4 h of ICU admission and exactly 72 h later. Early gut pathogen colonization was classified as the new presence (based on culture of rectal swabs) of one or more of the following organisms of interest: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant (VRE), and Gram-negative bacteria that showed multidrug resistance (MDR) or third generation Cephalosporin resistance (Ceph-R). Clinical risk factors for early acquisition of gut pathogen colonization were captured using the Acute Physiology and Chronic Health Evaluation IV (APACHE IV) scoring system.

FINDINGS

Among 131 patients who were swabbed at ICU admission and 72 h later, the rates of gut pathogen colonization at ICU admission were 11.4%, 10.6%, 38.6%, and 8.3% for MRSA, VRE, MDR and Ceph-R Gram-negatives respectively. Among the patients who were negative for a given pathogen at ICU admission, the rates of early acquisition of gut pathogen colonization were 7.8% for MRSA (95% CI 3.6 to 14.2%), 7.7% for VRE (95% CI 3.6 to 14.1%), 11.3% for MDR Gram-negatives (95% CI 4.4 to 18.8%), and 4.2% for Ceph-R Gram-negatives (95% CI 1.4 to 9.5%). There were no clinical risk factors which independently predicted early acquisition of gut pathogen colonization.

INTERPRETATION

Early gut pathogen colonization was common in the ICU, but our single-center study could not identify any clinical risk factors which were significantly associated with acquisition of gut pathogens.

Complementary supramolecular drug associates in perfecting the multidrug therapy against multidrug resistant bacteria

The inappropriate and inconsistent use of antibiotics in combating multidrug-resistant bacteria exacerbates their drug resistance through a few distinct pathways. Firstly, these bacteria can accumulate multiple genes, each conferring resistance to a specific drug, within a single cell. This accumulation usually takes place on resistance plasmids (R). Secondly, multidrug resistance can arise from the heightened expression of genes encoding multidrug efflux pumps, which expel a broad spectrum of drugs from the bacterial cells. Additionally, bacteria can also eliminate or destroy antibiotic molecules by modifying enzymes or cell walls and removing porins. A significant limitation of traditional multidrug therapy lies in its inability to guarantee the simultaneous delivery of various drug molecules to a specific bacterial cell, thereby fostering incremental drug resistance in either of these paths. Consequently, this approach prolongs the treatment duration. Rather than using a biologically unimportant coformer in forming cocrystals, another drug molecule can be selected either for protecting another drug molecule or, can be selected for its complementary activities to kill a bacteria cell synergistically. The development of a multidrug cocrystal not only improves tabletability and plasticity but also enables the simultaneous delivery of multiple drugs to a specific bacterial cell, philosophically perfecting multidrug therapy. By adhering to the fundamental tenets of multidrug therapy, the synergistic effects of these drug molecules can effectively eradicate bacteria, even before they have the chance to develop resistance. This approach has the potential to shorten treatment periods, reduce costs, and mitigate drug resistance. Herein, four hypotheses are presented to create complementary drug cocrystals capable of simultaneously reaching bacterial cells, effectively destroying them before multidrug resistance can develop. The ongoing surge in the development of novel drugs provides another opportunity in the fight against bacteria that are constantly gaining resistance to existing treatments. This endeavour holds the potential to combat a wide array of multidrug-resistant bacteria.

Perceptions of antibiotic stewardship programmes and determinants of antibiotic prescribing patterns among physicians in tertiary hospitals in Bangladesh: implications for future policy and practice

BACKGROUND

The concerning growth of antimicrobial resistance (AMR) renders common infections life-threatening due to irrational antibiotic use and a lack of effective antimicrobial stewardship programmes (ASPs).

AIM

To investigate the awareness, perceptions and practices of physicians regarding ASPs, AMR and antibiotic prescribing in tertiary care hospitals in Bangladesh.

METHODS

This hospital-based cross-sectional survey was conducted in 11 tertiary care hospitals across Bangladesh between September 2020 and January 2021. A semi-structured questionnaire was administered through face-to-face interviews for data collection. Descriptive and multi-variate analyses were performed using STATA Version 13.

RESULTS

In total, 559 physicians were enrolled in this survey. Overall, 40.6% [95% confidence interval (CI) 36.5-44.8] of physicians reported being aware of ASPs, and this figure was higher in public hospitals compared with private hospitals (43.8% vs 27.1%). None of the study hospitals had any ASP initiatives. More than half (55.1%) of the participants were willing to receive feedback from an ASP on their antibiotic selection. Only 30.9% of respondents stated that they wait for the findings of microbiological tests before prescribing antibiotics, although challenges included empiric use of broad-spectrum antibiotics, delayed laboratory results and the existence of drug-resistant patients. In contrast, physicians aware of ASPs were 33% (adjusted odds ratio 0.67, 95% CI 0.45-0.98; P=0.033) less likely to wait for laboratory results before prescribing antibiotics. However, 42.5% of physicians considered patient affordability of purchasing antibiotics when prescribing.

CONCLUSIONS

Physicians' fundamental knowledge of ASPs and rational antibiotic prescription were found to fall short of the standard. Context-specific and integrated ASP activities, availability and use of guidelines, and improved laboratory facilities are required to battle AMR in Bangladesh.

Association of short-course antimicrobial therapy and bacterial resistance in acute cholangitis: Retrospective cohort study

Background and study aims Although the number of resistant bacteria tends to increase with prolonged antimicrobial therapy, no studies have examined the relationship between the duration of antimicrobial therapy and increase in the number of resistant bacteria in acute cholangitis. We hypothesized that the short-term administration of antimicrobial agents in acute cholangitis would suppress bacterial resistance. Patients and methods This was a single-center, retrospective, observational study of patients with acute cholangitis admitted between January 2018 and June 2020 who met the following criteria: successful biliary drainage, positive blood or bile cultures, bacteria identified from cultures sensitive to antimicrobials, and subsequent cholangitis recurrence by January 2022. The patients were divided into two groups: those whose causative organisms at the time of recurrence became resistant to the antimicrobial agents used at the time of initial admission (resistant group) and those who remained susceptible (susceptible group). Multivariate analysis was used to examine risk factors associated with the development of resistant pathogens. Multivariate analysis investigated antibiotics used with the length of 3 days or shorter after endoscopic retrograde cholangiopancreatography (ERCP) and previously reported risk factors for the development of bacterial resistance. Results In total, 89 eligible patients were included in this study. There were no significant differences in patient background or ERCP findings between the groups. The use of antibiotics, completed within 3 days after ERCP, was associated with a lower risk of developing bacterial resistance (odds ratio, 0.17; 95% confidence interval, 0.04-0.65; P =0.01). Conclusions In acute cholangitis, the administration of antimicrobials within 3 days of ERCP may suppress the development of resistant bacteria.