Enumerating the economic cost of antimicrobial resistance per antibiotic consumed to inform the evaluation of interventions affecting their use

The hidden dangers lurking at home: Unveiling the prevalence of leftover antibiotics and its associated factors among Lebanese households

Background

Antimicrobial Resistance (AMR) is a major global concern. Irrational use of antibiotics including self-medication (SM) with leftovers without a medical prescription can be a leading cause. This study aimed to investigate the prevalence and related factors of leftover antibiotics (LA) in Lebanese households.

Study design

A cross-sectional study of the Lebanese population was conducted between March and October 2022.

Methods

Through random proportional stratified sampling, a total of 494 families participated in this study. Data collection was carried out through phone calls using a comprehensive and reviewed questionnaire. The data was then analyzed using SPSS version 26. Logistic regression was utilized to identify the factors associated with LA, with the presence of LA in households as the dependent variable and other factors such as age, region of residence, and presence of elderly individuals at home as the independent variables.

Results

Among selected households, 118 households (23.89%) had LA. The most common type of antibiotic found was penicillin (59.84%). Most of the LA were in the form of tablets and capsules (94%) with valid expiration dates (87%). Antibiotics were mainly prescribed by doctors (61%), and the main reason for prescribing was acute respiratory tract infections (47.46%). SM was reported by 42.37% of the families with LA. A family with elderly patients (p = 0.002; OR = 2.23; 95% CI = 1.33-3.73) and those residing in Mount Lebanon (p = 0.019; OR = 2.28; 95% CI = 1.14-4.56) had significantly higher odds of having LA.

Conclusion

Leftover antibiotics were found in nearly a quarter of the addressed Lebanese families. Therefore, public educational campaigns should be launched to limit injudicious antibiotic use including SM, and to promote proper disposal of any leftovers. It is also crucial to adopt the One Health approach by developing national programs for the safe disposal of LA and implementing regulations to restrict the distribution of antibiotics in pharmacies without a prescription.

Cost-effectiveness analysis of procalcitonin and lung ultrasonography guided antibiotic prescriptions in primary care

Antimicrobial resistance comes with high morbidity and mortality burden, and ultimately high impact on healthcare and social costs. Efficient strategies are needed to limit antibiotic overuse. This paper investigates the cost-effectiveness of testing patients with lower respiratory tract infection with procalcitonin, either at the point-of-care only or combined with lung ultrasonography. These diagnostic tools help detect the presence of bacterial pneumonia, guiding prescription decisions. The clinical responses of these strategies were studied in the primary care setting. Evidence is needed on their cost-effectiveness. We used data from a cluster-randomized bi-centric clinical trial conducted in Switzerland and estimated patient-level costs using data on resource use to which we applied Swiss tariffs. Combining the incremental costs of the two strategies and the reduction in the 28-days antibiotic prescription rate (APR) compared to usual care, we calculated Incremental Cost-Effectiveness Ratios (ICER). We also used the Cost-Effectiveness Acceptability Curve as an analytical decision-making tool. The robustness of the findings is ensured by Probabilistic Sensitivity Analysis and scenario analysis. In the base case scenario, the ICER compared to usual care is $2.3 per percentage point (pp) reduction in APR for the procalcitonin group, and $4.4 for procalcitonin-ultrasound combined. Furthermore, we found that for a willingness to pay per patient of more than $2 per pp reduction in the APR, procalcitonin is the strategy with the highest probability to be cost-effective. Our findings suggest that testing patients with respiratory symptoms with procalcitonin to guide antibiotic prescription in the primary care setting represents good value for money.

Randomised multicentre effectiveness trial of rapid syndromic testing by panel assay in children presenting to European emergency departments with acute respiratory infections-trial protocol for the ADEQUATE Paediatric trial

INTRODUCTION

Syndromic panel assays, that is, using one test to simultaneously target multiple pathogens with overlapping signs and symptoms, have been integrated into routine paediatric care over the past decade, mainly for more severely ill and hospitalised patients. Their wider availability and short turnaround times open the possibility to apply them to non-hospitalised patients as well. In this context, it is important to trial how clinicians make use of pathogen detection data and if their early availability influences management decisions, particularly antibiotic use and hospitalisation.

METHODS AND ANALYSIS

Advanced Diagnostics for Enhanced QUality of Antibiotic prescription in respiratory Tract infections in Emergency rooms is an individually randomised, controlled, open-label effectiveness trial comparing the impact of a respiratory pathogen panel assay (BIOFIRE Respiratory Panel 2.1plus) used as a rapid syndromic test on nasopharyngeal swabs in addition to the standard of care versus standard of care alone. The trial will 1:1 randomise 520 participants under the age of 18 at 7 paediatric emergency departments in 5 European countries. Inclusion criteria for the trial consist of two sets, with the first describing respiratory tract infections in paediatric patients and the second describing the situation of potential management uncertainty in which test results may immediately affect management decisions. Enrolment started in July 2021 and is expected to be completed in early 2024. We will perform a two-sample t-test assuming a pooled variance estimate to compare the log-transformed mean time on antibiotic treatment (in hours) and number of days alive out of the hospital within 14 days after study enrolment between the control and intervention arms.

ETHICS AND DISSEMINATION

The trial protocol and materials were approved by research ethics committees in all participating countries. The respiratory pathogen panel assay is CE marked (assessed to meet European regulations) and FDA (United States Food and Drug Administration) cleared for diagnostic use. Participants and caregivers provide informed consent prior to study procedures commencing. The trial results will be published in peer-reviewed journals and at national and international conferences. Key messages will also be disseminated via press and social media where appropriate.

TRIAL REGISTRATION NUMBER

NCT04781530.

Cost-effectiveness analysis of a multiplex lateral flow rapid diagnostic test for acute non-malarial febrile illness in rural Cambodia and Bangladesh

Background

Multiplex lateral flow rapid diagnostic tests (LF-RDTs) may aid management of patients with acute non-malarial febrile illness (NMFI) in rural south and southeast Asia. We aimed to evaluate the cost-effectiveness in Cambodia and Bangladesh of a putative, as-yet-undeveloped LF-RDT capable of diagnosing enteric fever and dengue, as well as measuring C-reactive protein (CRP) to guide antibiotic prescription, in primary care patients with acute NMFI.

Methods

A country-specific decision tree model-based cost-effectiveness analysis was conducted from a health system plus limited societal perspective considering the cost of antimicrobial resistance. Parameters were based on data from a large observational study on the regional epidemiology of acute febrile illness, published studies, and procurement price lists. Costs were expressed in US$ (value in 2022), and cost-effectiveness evaluated by comparing incremental cost-effectiveness ratios with conservative opportunity cost-based willingness-to-pay thresholds and the more widely used threshold of per capita gross domestic product (GDP).

Findings

Compared to standard of care, LF-RDT-augmented clinical assessment was dominant in Cambodia, being more effective and cost-saving. The cost per disability-adjusted life year (DALY) averted in Bangladesh was US$482, slightly above the conservative opportunity cost-based willingness-to-pay threshold of US$388 and considerably lower than the GDP-based threshold of US$2687. The intervention remained dominant in Cambodia and well below the GDP-based threshold in Bangladesh when antimicrobial resistance costs were disregarded.

Interpretation

These findings provide guidance for academic, industry, and policymaker stakeholders involved in acute NMFI diagnostics. While definitive conclusions cannot be made in the absence of established thresholds, our results suggest that similar results are highly likely in some target settings and possible in others.

Funding

Wellcome Trust, UK Government, Royal Australasian College of Physicians, and Rotary Foundation.

Chitosan-Loaded Lagenaria siceraria and Thymus vulgaris Potentiate Antibacterial, Antioxidant, and Immunomodulatory Activities against Extensive Drug-Resistant Pseudomonas aeruginosa and Vancomycin-Resistant Staphylococcus aureus: In Vitro and In Vivo Approaches

Antimicrobial resistance poses considerable issues for current clinical care, so the modified use of antimicrobial agents and public health initiatives, coupled with new antimicrobial approaches, may help to minimize the impact of multidrug-resistant (MDR) bacteria in the future. This study aimed to evaluate the antimicrobial, antioxidant, and immunomodulatory activities of Lagenaria siceraria, Thymus vulgaris, and their chitosan nanocomposites against extensive drug-resistant (XDR) Pseudomonas aeruginosa and vancomycin-resistant Staphylococcus aureus (VRSA) using both in vitro and in vivo assays. The in vitro antimicrobial susceptibilities of P. aeruginosa and VRSA strains revealed 100% sensitivity to imipenem (100%). All P. aeruginosa strains were resistant to cefoxitin, cefepime, trimethoprim + sulfamethoxazole, and fosfomycin. However, S. aureus strains showed a full resistance to cefoxitin, amoxicillin, ampicillin, erythromycin, chloramphenicol, and fosfomycin (100% each). Interestingly, all S. aureus strains were vancomycin-resistant (MIC = 32-512 μg/mL), and 90% of P. aeruginosa and S. aureus strains were XDR. The antimicrobial potential of Lagenaria siceraria and Thymus vulgaris nanocomposites with chitosan nanoparticles demonstrated marked inhibitory activities against XDR P. aeruginosa and VRSA strains with inhibition zones' diameters up to 50 mm and MIC values ranging from 0.125 to 1 μg/mL and 1 to 8 μg/mL, respectively. The results of the in vivo approach in male Sprague Dawley rats revealed that infection with P. aeruginosa and S. aureus displayed significant changes in biochemical, hematological, and histopathological findings compared to the negative control group. These values returned to the normal range after treatment by chitosan nanoparticles, either loaded with Lagenaria siceraria or Thymus vulgaris. Real-time quantitative polymerase chain reaction (RT-qPCR) findings presented significant upregulation of the relative expression of the IL10 gene and downregulation of the IFNG gene throughout the experimental period, especially after treatment with chitosan nanoparticles loaded either with Lagenaria siceraria or Thymus vulgaris in comparison to the positive control groups. In conclusion, this is the first report suggesting the use of Lagenaria siceraria and Thymus vulgaris nanocomposites with chitosan nanoparticles as a promising contender for combating XDR P. aeruginosa and VRSA infections as well as a manager for inflammatory situations and oxidative stress-related disorders.

Antimicrobial Activity of Bacillus amyloliquefaciens BS4 against Gram-Negative Pathogenic Bacteria

Worldwide, bacterial resistance is one of the most severe public health problems. Currently, the failure of antibiotics to counteract superbugs highlights the need to search for new molecules with antimicrobial potential to combat them. The objective of this research was to evaluate the antimicrobial activity of Bacillus amyloliquefaciens BS4 against Gram-negative bacteria. Thirty yeasts and thirty-two Bacillus isolates were tested following the agar well-diffusion method. Four Bacillus sp. strains (BS3, BS4, BS17, and BS21) showed antagonistic activity against E. coli ATCC 25922 using bacterial culture (BC) and the cell-free supernatant (CFS), where the BS4 strain stood out, showing inhibitory values of 20.50 ± 0.70 mm and 19.67 ± 0.58 mm for BC and CFS, respectively. The Bacillus sp. BS4 strain can produce antioxidant, non-hemolytic, and antimicrobial metabolites that exhibit activity against several microorganisms such as Salmonella enterica, Klebsiella pneumoniae, Shigella flexneri, Enterobacter aerogenes, Proteus vulgaris, Yersinia enterocolitica, Serratia marcescens, Aeromonas sp., Pseudomonas aeruginosa, Candida albicans, and Candida tropicalis. According to the characterization of the supernatant, the metabolites could be proteinaceous. The production of these metabolites is influenced by carbon and nitrogen sources. The most suitable medium to produce antimicrobial metabolites was TSB broth. The one-factor-at-a-time method was used to standardize parameters such as pH, agitation, temperature, carbon source, nitrogen source, and salts, resulting in the best conditions of pH 7, 150 rpm, 28 °C, starch (2.5 g/L), tryptone (20 g/L), and magnesium sulfate (0.2 g/L), respectively. Moreover, the co-culture was an excellent strategy to improve antimicrobial activity, achieving maximum antimicrobial activity with an inhibition zone of 21.85 ± 1.03 mm. These findings position the Bacillus amyloliquefaciens BS4 strain as a promising candidate for producing bioactive molecules with potential applications in human health.

Leveraging Large Data, Statistics, and Machine Learning to Predict the Emergence of Resistant E. coli Infections

Drug-resistant Gram-negative bacterial infections, on average, increase the length of stay (LOS) in U.S. hospitals by 5 days, translating to approximately $15,000 per patient. We used statistical and machine-learning models to explore the relationship between antibiotic usage and antibiotic resistance over time and to predict the clinical and financial costs associated with resistant E. coli infections. We acquired data on antibiotic utilization and the resistance/sensitivity of 4776 microbial cultures at a Kaiser Permanente facility from April 2013 to December 2019. The ARIMA (autoregressive integrated moving average), neural networks, and random forest time series algorithms were employed to model antibiotic resistance trends. The models' performance was evaluated using mean absolute error (MAE) and root mean squared error (RMSE). The best performing model was then used to predict antibiotic resistance rates for the year 2020. The ARIMA model with cefazolin, followed by the one with cephalexin, provided the lowest RMSE and MAE values without signs of overfitting across training and test datasets. The study showed that reducing cefazolin usage could decrease the rate of resistant E. coli infections. Although piperacillin/tazobactam did not perform as well as cefazolin in our time series models, it performed reasonably well and, due to its broad spectrum, might be a practical target for interventions in antimicrobial stewardship programs (ASPs), at least for this particular facility. While a more generalized model could be developed with data from multiple facilities, this study acts as a framework for ASP clinicians to adopt statistical and machine-learning approaches, using region-specific data to make effective interventions.

Cost-effectiveness of point-of-care diagnostics for AMR: a systematic review

BACKGROUND

Antimicrobial resistance (AMR) is a major threat to global health. By 2050, it is forecast that AMR will cause 10 million deaths and cost 100 trillion USD annually. Point-of-care tests (POCTs) may represent a cost-effective approach to reduce AMR.

OBJECTIVES

We systematically reviewed which POCTs addressing AMR have undergone economic evaluation in primary and secondary healthcare globally, how these POCTs have been economically evaluated, and which are cost-effective in reducing antimicrobial prescribing or the burden of AMR. Clinical cost-effectiveness was additionally addressed.

METHODS

This systematic review, accordant with PRISMA guidelines, was pre-registered on PROSPERO (CRD42022315192). MEDLINE, PubMed, Embase, Cochrane Library, and Google Scholar were searched from 2000 to 2023 for relevant publications. Quality assessment was performed using the Consensus of Health Economic Criteria.

RESULTS

The search strategy identified 1421 studies, of which 20 met the inclusion criteria. The most common POCTs assessed were for respiratory infections (n = 10), STIs (n = 3), and febrile patients in low- and middle-income countries (n = 3). All studies assessed costs from a healthcare provider perspective; five additionally considered the societal cost of AMR.Eighteen studies identified POCT strategies that reduced antimicrobial prescribing. Of these, 10 identified POCTs that would be considered cost-effective at a willingness-to-pay (WTP) threshold of £33.80 per antibiotic prescription avoided. Most POCT strategies improved clinical outcomes (n = 14); the remainder were clinically neutral.

CONCLUSIONS

There is evidence that some POCTs are cost-effective in reducing antimicrobial prescribing, with potential concomitant clinical benefits. Such interventions-especially CRP POCTs in both high- and low-income settings-merit further, large-scale clinical evaluation.

An insights into emerging trends to control the threats of antimicrobial resistance (AMR): an address to public health risks

Antimicrobial agents are used to treat microbial ailments, but increased use of antibiotics and exposure to infections in healthcare facilities and hospitals as well as the excessive and inappropriate use of antibiotics at the society level lead to the emergence of multidrug-resistant (MDR) bacteria. Antimicrobial resistance (AMR) is considered a public health concern and has rendered the treatment of different infections more challenging. The bacterial strains develop resistance against antimicrobial agents by limiting intracellular drug accumulation (increasing efflux or decreasing influx of antibiotics), modification and inactivation of drugs and its targets, enzymatic inhibition, and biofilm formation. However, the driving factors of AMR include the sociocultural and economic circumstances of a country, the use of falsified and substandard medicines, the use of antibiotics in farm animals, and food processing technologies. These factors make AMR one of the major menaces faced by mankind. In order to promote reciprocal learning, this article summarizes the current AMR situation in Pakistan and how it interacts with the health issues related to the COVID-19 pandemic. The COVID-19 pandemic aids in illuminating the possible long-term impacts of AMR, which are less immediate but not less severe since their measures and effects are equivalent. Impact on other sectors, including the health industry, the economy, and trade are also discussed. We conclude by summarizing the several approaches that could be used to address this issue.

Antimicrobial resistance, virulence profile, and genetic analysis of ESBL-producing Escherichia coli isolated from Nile tilapia in fresh markets and supermarkets in Thailand

This study investigated the prevalence and antimicrobial resistance (AMR) of Escherichia coli (E. coli) in Nile tilapia from fresh markets and supermarkets. A total of samples (n = 828) were collected from Nile tilapia including fish flesh (n = 276), liver and kidney (n = 276), and intestine (n = 276). Overall prevalence of fecal coliforms (61.6%) and E. coli (53.0%) were observed. High prevalence of E. coli was found in the intestine (71.4%), followed by the liver and kidney (45.7%). The highest prevalence of resistance was commonly found against tetracycline (78.5%), ampicillin (72.8%), and sulfamethoxazole (45.6%) with resistance to only tetracycline (15.2%) as the most common antibiogram. The prevalence of multidrug resistance (MDR) (54.4%) and Extended-spectrum beta-lactamases (ESBLs) (5.7%) were examined. The predominant virulence genes (n = 158) were st (14.6%), followed by eaeA (0.6%). The blaTEM (73.4%), tetA (65.2%), and qnrS (57.6%). There is statistical significance between Nile tilapia from fresh markets and supermarkets. Based on logistic regression analysis, ampicillin-resistant E. coli was statistically associated with the phenotypic resistance to tetracycline and trimethoprim, and the presence of blaTEM and tetA (p < 0.05). Further investigation of AMR transference and their mechanisms is needed for AMR control.

Discovering targeted inhibitors for Escherichia coli efflux pump fusion proteins using computational and structure-guided approaches

Multidrug resistance pathogens causing infections and illness remain largely untreated clinically. Efflux pumps are one of the primary processes through which bacteria develop resistance by transferring antibiotics from the interior of their cells to the outside environment. Inhibiting these pumps by developing efficient derivatives appears to be a promising strategy for restoring antibiotic potency. This investigation explores literature-reported inhibitors of E. coli efflux pump fusion proteins AcrB-AcrA and identify potential chemical derivatives of these inhibitors to overcome the limitations. Using computational and structure-guided approaches, a study was conducted with the selected inhibitors (AcrA:25-AcrB:59) obtained by data mining and their derivatives (AcrA:857-AcrB:3891) to identify their inhibitory effect on efflux pump using virtual screening, molecular docking and density functional theory (DFT) calculations. The finding indicates that Compound 2 (ZINC000072136376) has shown better binding and a significant inhibitory effect on AcrA, while Compound 3 (ZINC000072266819) has shown stronger binding and substantial inhibition effect on both non-mutant and mutated AcrB subunits. The identified derivatives could exhibit a better inhibitor and provide a potential approach for restoring the actions of resistant antibiotics.

Designing of fragment based inhibitors with improved activity against E. coli AmpC β-lactamase compared to the conventional antibiotics

One of the most common primary resistance mechanism of multi-drug resistant (MDR) Gram negative pathogenic bacteria to combat β-lactam antibiotics, such as penicillins, cephalosporins and carbapenems is the generation of β- lactamases. The uropathogenic E. coli is mostly getting multi-drug resistance due to the synthesis of AmpC β-lactamases and therefore new antibiotics and inhibitors are needed to treat the evolving infections. The current study was designed for targetting AmpC β-lactamase of E. coli using molecular docking based virtual screening, linking fragments for designing novel compounds and binding mode analysis using molecular dynamic simulation with target protein. The FCH group all-purpose fragment library consisting of 9388 fragments has been screened against AmpC β-lactamase protein of E. coli and the antibiotics and anti-infectives used in treatment of Urinary tract Infections (UTIs) were also screened with AmpC β-lactamase protein. Among the 9388 fragments, 339 fragment candidates were selected and linked with cefepime antibiotic having maximum binding affinity for AmpC target protein. Computational analysis of interactions as well as molecular dynamics (MD) simulations were also conducted for identifying the most promising ligand-pocket complexes from docking investigations to comprehend their thermodynamic properties and verify the docking outcomes as well. Overall, the linked complexes (LCs) showed good binding interactions with AmpC β-lactamase. Interestingly, our fragment-based LCs remained relatively stable in comparison with cefepime antibiotic. Moreover, S12 fragment linked complex remained the most stable during 50 ns with remarkable number of interactions indicating it as promising candidate in novel lead discovery against MDR E. coli infections.

Evaluating the contribution of antimicrobial use in farmed animals to global antimicrobial resistance in humans

Antimicrobial resistance (AMR) is currently regarded by the World Health Organization (WHO) as one of the most significant risks to global public health. The most critical causes of AMR infections in humans are the misuse and overuse of antimicrobials in humans and farmed animals. The rising global demand for food of animal origin encourages the increase of animal production worldwide, especially in developing countries. Simultaneously, current farming practices often extensively use antimicrobials on animals, influencing bacterial AMR incidence. This study aims to evaluate the correlation between antimicrobial use (AMU) in farmed animals and the detection of AMR infections in humans, the effects of enforcing laws in animal farming in a country on AMR situation in the neighbors, and the potential of AMR to spread from one country to another. Using data from 30 largest animal-producing countries in different regions of the world, between 2010 and 2020, and a Spatial Durbin Model (SDM), we found that AMU in farmed animals increases AMR in humans and there is a spatial dependence between countries regarding AMR spreading. Such findings indicate that a globally coordinated strategy regulating AMU on farmed animals may reduce AMR emergence and worldwide spreading.

Adherence to evidence-based implementation of antimicrobial treatment guidelines among prescribers in sub-Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Adherence to evidence-based standard treatment guidelines (STGs) enable healthcare providers to deliver consistently appropriate diagnosis and treatment. Irrational use of antimicrobials significantly contributes to antimicrobial resistance in sub-Saharan Africa (SSA).  The best available evidence is needed to guide healthcare providers on adherence to evidence-based implementation of STGs. This systematic review and meta-analysis aimed to determine the pooled prevalence of adherence to evidence-based implementation of antimicrobial treatment guidelines among prescribers in SSA.

METHODS

The review followed the JBI methodology for systematic reviews of prevalence data. CINAHL, Embase, PubMed, Scopus, and Web of Science databases were searched with no language and publication year limitations. STATA version 17 were used for meta-analysis. The publication bias and heterogeneity were assessed using Egger's test and the I2 statistics. Heterogeneity and publication bias were validated using Duval and Tweedie's nonparametric trim and fill analysis using the random-effect analysis. The summary prevalence and the corresponding 95% confidence interval (CI) of healthcare professionals' compliance with evidence-based implementation of STG were estimated using random effect model. The review protocol has been registered with PROSPERO code CRD42023389011. The PRISMA flow diagram and checklist were used to report studies included, excluded and their corresponding section in the manuscript.

RESULTS

Twenty-two studies with a total of 17,017 study participants from 14 countries in sub-Saharan Africa were included. The pooled prevalence of adherence to evidence-based implementation of antimicrobial treatment guidelines in SSA were 45%. The pooled prevalence of the most common clinical indications were respiratory tract (35%) and gastrointestinal infections (18%). Overall prescriptions per wards were inpatients (14,413) and outpatients (12,845). Only 391 prescribers accessed standard treatment guidelines during prescription of antimicrobials.

CONCLUSIONS

Healthcare professionals' adherence to evidence-based implementation of STG for antimicrobial treatment were low in SSA. Healthcare systems in SSA must make concerted efforts to enhance prescribers access to STGs through optimization of mobile clinical decision support applications. Innovative, informative, and interactive strategies must be in place by the healthcare systems in SSA to empower healthcare providers to make evidence-based clinical decisions informed by the best available evidence and patient preferences, to ultimately improving patient outcomes and promoting appropriate antimicrobial use.

Economic evaluation of antimicrobial resistance in curable sexually transmitted infections; a systematic review and a case study

OBJECTIVE

To provide a summary of the economic and methodological evidence on capturing antimicrobial resistance (AMR) associated costs for curable sexually transmitted infections (STIs). To explore approaches for incorporating the cost of AMR within an economic model evaluating different treatment strategies for gonorrhoea, as a case study.

METHODS

A systematic review protocol was registered on PROSPERO (CRD42022298232). MEDLINE, EMBASE, CINAHL, Cochrane Library, International Health Technology Assessment Database, National Health Service Economic Evaluation Database, and EconLit databases were searched up to August 2022. Included studies were analysed, quality assessed and findings synthesised narratively. Additionally, an economic evaluation which incorporated AMR was undertaken using a decision tree model and primary data from a randomised clinical trial comparing gentamicin therapy with standard treatment (ceftriaxone). AMR was incorporated into the evaluation using three approaches-integrating the additional costs of treating resistant infections, conducting a threshold analysis, and accounting for the societal cost of resistance for the antibiotic consumed.

RESULTS

Twelve studies were included in the systematic review with the majority focussed on AMR in gonorrhoea. The cost of ceftriaxone resistant gonorrhoea and the cost of ceftriaxone sparing strategies were significant and related to the direct medical costs from persistent gonorrhoea infections, sequelae of untreated infections, gonorrhoea attributable-HIV transmission and AMR testing. However, AMR definition, the collection and incorporation of AMR associated costs, and the perspectives adopted were inconsistent or limited. Using the review findings, different approaches were explored for incorporating AMR into an economic evaluation comparing gentamicin to ceftriaxone for gonorrhoea treatment. Although the initial analysis showed that ceftriaxone was the cheaper treatment, gentamicin became cost-neutral if the clinical efficacy of ceftriaxone reduced from 98% to 92%. By incorporating societal costs of antibiotic use, gentamicin became cost-neutral if the cost of ceftriaxone treatment increased from £4.60 to £8.44 per patient.

CONCLUSIONS

Inclusion of AMR into economic evaluations may substantially influence estimates of cost-effectiveness and affect subsequent treatment recommendations for gonorrhoea and other STIs. However, robust data on the cost of AMR and a standardised approach for conducting economic evaluations for STI treatment which incorporate AMR are lacking, and requires further developmental research.

Antibacterial activity of thymoquinone derivative

Natural products such as terpenoidal compounds have been extremely tested against pathogenic bacteria. Researches are frequently carried out to find out new natural, semisynthetic and synthetic antibacterial agents due to problems of resistance. Thymoquinone derivative was obtained in our previous study and the current research is a continuation. The antibacterial activity of a monoterpenoid; thymoquinone derivative, 5-isopropyl-2-methyloxepine-1-one (1) has been evaluated for the first time by following the Agar cup bioassay method employed. The bacterial strains used in this study were Escherichia coli and Bacillus subtilis. Compound 1 showed moderate activity against Gram-positive organism; B. subtilis and good activity against Gram-negative species; E. coli with zones of inhibition (ZOI) 10.0 ± 0.2 mm and 11.0 ± 0.2 mm against E. coli and B. subtilis, respectively, and in comparison with antibiotic, imipenem. The zones of inhibition were calculated as the mean of the triplicate. The antibacterial activity of thymoquinone derivative 1 could be explained by the presence of unsaturated lactone.

Antibiotic-Resistant Strains of Helicobacter pylori in 50 Antibiotic Treatment-Naive Children in Northeast Poland Diagnosed by Gastric or Duodenal Biopsy Between February 2019 and May 2022

BACKGROUND In recent years, an increasing prevalence of Helicobacter pylori resistance to antibiotics has been observed. The aim of this study was to assess antibiotic resistance of Helicobacter pylori in previously untreated children from northeast Poland. MATERIAL AND METHODS Inclusion criteria comprised suspicion of Helicobacter pylori infection based on the presence of Helicobacter pylori antigen in the stool and/or characteristic macroscopic lesions seen on esophagogastroduodenoscopy. Samples of the gastric and/or duodenal mucosa were collected from 82 children with a median age of 13 years (range 3-17) during esophagogastroduodenoscopy between February 2019 and May 2022. The material was cultured, and positive Helicobacter pylori strains were tested for drug resistance to amoxicillin, metronidazole, and clarithromycin using the quantitative antibiotic concentration gradient stripe method E-test. RESULTS Based on biopsy culture, Helicobacter pylori infection was confirmed in 50 (61%) children. Helicobacter pylori resistance was most common to clarithromycin (n=19; 38%), followed by metronidazole (n=15; 30%), and the least frequent to amoxicillin (n=13; 26%). The resistance to 1 antibiotic was found in 14 children (28%). Double-drug resistance was noted in 3 children (6%) and triple drug resistance in 9 children (18%). In the whole group, 24 children (48%) were susceptible to all 3 antibiotics. CONCLUSIONS In this study, conducted for the first time in treatment-naïve children in northeast Poland, we found a high proportion of Helicobacter pylori strains resistant to at least 1 antibiotic. Our results may help in the appropriate choice of antibiotics for treatment of Helicobacter pylori in our region.

An Overview of Preventive Strategies and the Role of Various Organizations in Combating Antimicrobial Resistance

The rise of antimicrobial resistance (AMR) is a major global public health threat due to excessive and inappropriate use of antibiotics and is responsible for prolonged illness, longer hospital stays, and economic burden to society. This article aims to review the factors, role of antimicrobial stewardship, preventive strategies, and role of various organizations in combating AMR. Three major factors of AMR are inappropriate and excessive utilization of antibiotics, nonadherence to infection control measures, and the emergence of pathogens that are resistant to multiple drugs. Antimicrobial stewardship initiatives play a vital role in promoting judicious and targeted utilization of antimicrobials, thereby safeguarding their efficacy and mitigating the emergence of resistance. Implementing such programs optimizes patient outcomes by ensuring that individuals receive the most suitable therapeutic interventions. International organizations have a vital role to play in addressing AMR by promoting the responsible use of antimicrobials, developing new drugs, and improving surveillance systems. As AMR's impact grows, it is critical to take a collaborative and interdisciplinary approach to mitigate its consequences effectively.

Application of CRISPR-Cas system in the diagnosis and therapy of ESKAPE infections

Antimicrobial-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens represent a global threat to human health. ESKAPE pathogens are the most common opportunistic pathogens in nosocomial infections, and a considerable number of their clinical isolates are not susceptible to conventional antimicrobial therapy. Therefore, innovative therapeutic strategies that can effectively deal with ESKAPE pathogens will bring huge social and economic benefits and ease the suffering of tens of thousands of patients. Among these strategies, CRISPR (clustered regularly interspaced short palindromic repeats) system has received extra attention due to its high specificity. Regrettably, there is currently no direct CRISPR-system-based anti-infective treatment. This paper reviews the applications of CRISPR-Cas system in the study of ESKAPE pathogens, aiming to provide directions for the research of ideal new drugs and provide a reference for solving a series of problems caused by multidrug-resistant bacteria (MDR) in the post-antibiotic era. However, most research is still far from clinical application.

Cost-effectiveness of testing for Mycoplasma genitalium among men who have sex with men in Australia

OBJECTIVES

Mycoplasma genitalium (MG) disproportionately affects men who have sex with men (MSM). We determined the cost-effectiveness of different testing strategies for MG in MSM, taking a healthcare provider perspective.

METHODS

We used inputs from a dynamic transmission model of MG among MSM living in Australia in a decision tree model to evaluate the impact of four testing scenarios on MG incidence: (1) no one tested; (2) symptomatic MSM; (3) symptomatic and high-risk asymptomatic MSM; (4) all MSM. We calculated the incremental cost-effectiveness ratios (ICERs) using a willingness-to-pay threshold of $A30 000 per quality-adjusted life year (QALY) gained. We explored the impact of adding an antimicrobial resistance (AMR) tax (ie, additional cost per antibiotic consumed) to identify the threshold, whereby any testing for MG is no longer cost-effective.

RESULTS

Testing only symptomatic MSM is the most cost-effective (ICER $3677 per QALY gained) approach. Offering testing to all MSM is dominated (ie, higher costs and lower QALYs gained compared with other strategies). When the AMR tax per antibiotic given was above $150, any testing for MG was no longer cost-effective.

CONCLUSION

Testing only symptomatic MSM is the most cost-effective option, even when the potential costs associated with AMR are accounted for (up to $150 additional cost per antibiotic given). For pathogens like MG, where there are anticipated future costs related to AMR, we recommend models that test the impact of incorporating an AMR tax as they can change the results and conclusions of cost-effectiveness studies.

Artificial Intelligence to Improve Antibiotic Prescribing: A Systematic Review

Introduction: The use of antibiotics leads to antibiotic resistance (ABR). Different methods have been used to predict and control ABR. In recent years, artificial intelligence (AI) has been explored to improve antibiotic (AB) prescribing, and thereby control and reduce ABR. This review explores whether the use of AI can improve antibiotic prescribing for human patients. Methods: Observational studies that use AI to improve antibiotic prescribing were retrieved for this review. There were no restrictions on the time, setting or language. References of the included studies were checked for additional eligible studies. Two independent authors screened the studies for inclusion and assessed the risk of bias of the included studies using the National Institute of Health (NIH) Quality Assessment Tool for observational cohort studies. Results: Out of 3692 records, fifteen studies were eligible for full-text screening. Five studies were included in this review, and a narrative synthesis was carried out to assess their findings. All of the studies used supervised machine learning (ML) models as a subfield of AI, such as logistic regression, random forest, gradient boosting decision trees, support vector machines and K-nearest neighbours. Each study showed a positive contribution of ML in improving antibiotic prescribing, either by reducing antibiotic prescriptions or predicting inappropriate prescriptions. However, none of the studies reported the engagement of AB prescribers in developing their ML models, nor their feedback on the user-friendliness and reliability of the models in different healthcare settings. Conclusion: The use of ML methods may improve antibiotic prescribing in both primary and secondary settings. None of the studies evaluated the implementation process of their models in clinical practices. Prospero Registration: (CRD42022329049).

Antimicrobial Resistance Patterns and Risk Factors Associated with ESBL-Producing and MDR Escherichia coli in Hospital and Environmental Settings in Lusaka, Zambia: Implications for One Health, Antimicrobial Stewardship and Surveillance Systems

Antimicrobial resistance (AMR) is a public health problem threatening human, animal, and environmental safety. This study assessed the AMR profiles and risk factors associated with Escherichia coli in hospital and environmental settings in Lusaka, Zambia. This cross-sectional study was conducted from April 2022 to August 2022 using 980 samples collected from clinical and environmental settings. Antimicrobial susceptibility testing was conducted using BD PhoenixTM 100. The data were analysed using SPSS version 26.0. Of the 980 samples, 51% were from environmental sources. Overall, 64.5% of the samples tested positive for E. coli, of which 52.5% were from clinical sources. Additionally, 31.8% were ESBL, of which 70.1% were clinical isolates. Of the 632 isolates, 48.3% were MDR. Most clinical isolates were resistant to ampicillin (83.4%), sulfamethoxazole/trimethoprim (73.8%), and ciprofloxacin (65.7%) while all environmental isolates were resistant to sulfamethoxazole/trimethoprim (100%) and some were resistant to levofloxacin (30.6%). The drivers of MDR in the tested isolates included pus (AOR = 4.6, CI: 1.9-11.3), male sex (AOR = 2.1, CI: 1.2-3.9), and water (AOR = 2.6, CI: 1.2-5.8). This study found that E. coli isolates were resistant to common antibiotics used in humans. The presence of MDR isolates is a public health concern and calls for vigorous infection prevention measures and surveillance to reduce AMR and its burdens.

A systematic literature review of economic evaluation studies of interventions impacting antimicrobial resistance

BACKGROUND

Antimicrobial resistance (AMR) is accelerated by widespread and inappropriate use of antimicrobials. Many countries, including those in low- and middle- income contexts, have started implementing interventions to tackle AMR. However, for many interventions there is little or no economic evidence with respect to their cost-effectiveness. To help better understand the scale of this evidence gap, we conducted a systematic literature review to provide a comprehensive summary on the value for money of different interventions affecting AMR.

METHODS

A systematic literature review was conducted of economic evaluations on interventions addressing AMR. a narrative synthesis of findings was produced. Systematic searches for relevant studies were performed across relevant databases and grey literature sources such as unpublished studies, reports, and other relevant documents. All identified economic evaluation studies were included provided that they reported an economic outcome and stated that the analysed intervention aimed to affect AMR or antimicrobial use in the abstract. Studies that reported clinical endpoints alone were excluded. Selection for final inclusion and data extraction was performed by two independent reviewers. A quality assessment of the evidence used in the included studies was also conducted.

RESULTS

28,597 articles were screened and 35 articles were identified that satisfied the inclusion criteria. The review attempted to answer the following questions: (1) What interventions to address AMR have been the subject of an economic evaluation? (2) In what types of setting (e.g. high-income, low-income, regions etc.) have these economic evaluations been focused? (3) Which interventions have been estimated to be cost-effective, and has this result been replicated in other settings/contexts? (4) What economic evaluation methods or techniques have been used to evaluate these interventions? (5) What kind and quality of data has been used in conducting economic evaluations for these interventions?

DISCUSSION

The review is one of the first of its kind, and the most recent, to systematically review the literature on the cost-effectiveness of AMR interventions. This review addresses an important evidence gap in the economics of AMR and can assist AMR researchers' understanding of the state of the economic evaluation literature, and therefore inform future research. Systematic review registration PROSPERO (CRD42020190310).

Economic burden of antimicrobial resistance and inappropriate empiric treatment in Thailand

Objective

To quantify the economic burden of bacterial antimicrobial resistance in Thailand and estimate potential savings from improving the rate of appropriate empiric treatment, where effective coverage is provided within the first days of infection.

Design

Cost-of-illness study.

Methods

A cost-calculator, decision-tree model was developed using published data and records from 3 Thai hospitals for patients hospitalized with antimicrobial-resistant infections between 2015 and 2019. Direct and indirect costs of antimicrobial-resistant infections were assessed over a 5-year time horizon, with outcomes derived separately for cases having received appropriate empiric treatment versus inappropriate empiric treatment. In a real-world scenario, outcomes were estimated using actual rates of inappropriate empiric treatment, and in a hypothetical scenario, outcomes were estimated using decreased rates of inappropriate empiric treatment.

Results

Over 5 years, in-hospital antimicrobial-resistant infections produced costs of approximately Thai baht (THB) 66.4 billion (USD 2.1 billion) in the real-world scenario and THB 65.8 billion (USD 2.1 billion) in the hypothetical scenario (0.9% cost savings relative to the real-world scenario). Most costs were attributable to income loss due to in-hospital mortality (real world: THB 53.7 billion [USD 1.7 billion]; 80.9% of costs; hypothetical: THB 53.2 billion [USD 1.7 billion]; 80.8% of costs) and hospitalization (real world: THB 10.3 billion [USD 330.8 million]; 15.5% of costs; hypothetical: THB 10.2 billion [USD 328.9 million]; 15.5% of costs).

Conclusions

In-hospital antimicrobial-resistant infections produced a substantial economic toll in Thailand. This public health burden could be reduced with a strategy aimed at decreasing the rate of patients receiving inappropriate empiric treatment.

Antibiotic Susceptibility Surveillance in the Punjab Province of Pakistan: Findings and Implications

Background and Objectives: The increase in antimicrobial resistance (AMR) across countries has seriously impacted the effective management of infectious diseases, with subsequent impact on morbidity, mortality and costs. This includes Pakistan. Antimicrobial surveillance activities should be mandatory to continually assess the extent of multidrug-resistant bacteria and the implications for future empiric prescribing. The objective of this retrospective observational study was to monitor the susceptibility pattern of microbes in Pakistan. Materials and Methods: Clinical samples from seven laboratories in Punjab, Pakistan were collected between January 2018 and April 2019, with Punjab being the most populous province in Pakistan. The isolates were identified and their antimicrobial susceptibility was tested using the Kirby-Bauer disc diffusion assay and micro broth dilution methods. The antibiotics assessed were those typically prescribed in Pakistan. Results: In total, 2523 bacterial cultural reports were studied. The most frequently isolated pathogens were Staphylococcus aureus (866, 34.3%), followed by Escherichia coli (814, 32.2%), Pseudomonas aeruginosa (454, 18.0%) and Klebsiella pneumoniae (269, 10.7%). Most pathogens were isolated from pus (1464, 58.0%), followed by urine (718, 28.5%), blood (164, 6.5%) and sputum (81, 3.2%). Conclusions: The findings suggest that current antimicrobial options are severally restricted in Pakistan due to the emergence of multidrug-resistant pathogens. This calls for urgent actions including initiating antimicrobial stewardship programs to enhance prudent prescribing of antibiotics. This includes agreeing on appropriate empiric therapy as part of agreed guidelines, in line with the WHO EML and AWaRe book, whilst awaiting culture reports. This is alongside other measures to reduce inappropriate antimicrobial prescribing and reverse the threat of rising AMR.

Individual and population level costs and health-related quality of life outcomes of third-generation cephalosporin resistant bloodstream infection in Blantyre, Malawi

Data which accurately enumerate the economic costs of antimicrobial resistance (AMR) in low- and middle- income countries are essential. This study aimed to quantify the impact of third-generation cephalosporin resistant (3GC-R) bloodstream infection (BSI) on economic and health related quality of life outcomes for adult patients in Blantyre, Malawi. Participants were recruited from a prospective, longitudinal cohort study of hospitalised patients with bloodstream infection caused by Enterobacterales at Queen Elizabeth Central Hospital (QECH). Primary costing studies were used to estimate the direct medical costs associated with the inpatient stay. Recruited participants were asked about direct non-medical and indirect costs associated with their admission and their health-related quality of life was measured using the EuroQol EQ-5D questionnaire. Multiple imputation was undertaken to account for missing data. Costs were adjusted to 2019 US Dollars. Cost and microbiology surveillance data from QECH, Blantyre was used to model the annual cost of, and quality-adjusted life years lost to, 3GC-R and 3GC-Susceptible BSI from 1998 to 2030 in Malawi. The mean health provider cost per participant with 3GC-R BSI was US$110.27 (95%CR; 22.60-197.95), higher than for those with 3GC-S infection. Patients with resistant BSI incurred an additional indirect cost of US$155.48 (95%CR; -67.80, 378.78) and an additional direct non-medical cost of US$20.98 (95%CR; -36.47, 78.42). Health related quality of life outcomes were poor for all participants, but participants with resistant infections had an EQ-5D utility score that was 0.167 (95% CR: -0.035, 0.300) lower than those with sensitive infections. Population level burden estimates suggest that in 2016, 3GC-R accounted for 84% of annual societal costs from admission with bloodstream infection and 82% of QALYs lost. 3GC-R bloodstream infection was associated with higher health provider and patient level costs than 3GC-S infection, as well as poorer HRQoL outcomes. We demonstrate a substantial current and future economic burden to society as a result of 3GC-R E. coli and Klebsiella spp. BSI, data urgently needed by policy makers to provide impetus for implementing strategies to reduce AMR.

Antibiotics for lower respiratory tract infection in children presenting in primary care: ARTIC-PC RCT

Background

Antimicrobial resistance is a global health threat. Antibiotics are commonly prescribed for children with uncomplicated lower respiratory tract infections, but there is little randomised evidence to support the effectiveness of antibiotics in treating these infections, either overall or relating to key clinical subgroups in which antibiotic prescribing is common (chest signs; fever; physician rating of unwell; sputum/rattly chest; shortness of breath).

Objectives

To estimate the clinical effectiveness and cost-effectiveness of amoxicillin for uncomplicated lower respiratory tract infections in children both overall and in clinical subgroups.

Design

Placebo-controlled trial with qualitative, observational and cost-effectiveness studies.

Setting

UK general practices.

Participants

Children aged 1-12 years with acute uncomplicated lower respiratory tract infections.

Outcomes

The primary outcome was the duration in days of symptoms rated moderately bad or worse (measured using a validated diary). Secondary outcomes were symptom severity on days 2-4 (0 = no problem to 6 = as bad as it could be); symptom duration until very little/no problem; reconsultations for new or worsening symptoms; complications; side effects; and resource use.

Methods

Children were randomised to receive 50 mg/kg/day of oral amoxicillin in divided doses for 7 days, or placebo using pre-prepared packs, using computer-generated random numbers by an independent statistician. Children who were not randomised could participate in a parallel observational study. Semistructured telephone interviews explored the views of 16 parents and 14 clinicians, and the data were analysed using thematic analysis. Throat swabs were analysed using multiplex polymerase chain reaction.

Results

A total of 432 children were randomised (antibiotics, n = 221; placebo, n = 211). The primary analysis imputed missing data for 115 children. The duration of moderately bad symptoms was similar in the antibiotic and placebo groups overall (median of 5 and 6 days, respectively; hazard ratio 1.13, 95% confidence interval 0.90 to 1.42), with similar results for subgroups, and when including antibiotic prescription data from the 326 children in the observational study. Reconsultations for new or worsening symptoms (29.7% and 38.2%, respectively; risk ratio 0.80, 95% confidence interval 0.58 to 1.05), illness progression requiring hospital assessment or admission (2.4% vs. 2.0%) and side effects (38% vs. 34%) were similar in the two groups. Complete-case (n = 317) and per-protocol (n = 185) analyses were similar, and the presence of bacteria did not mediate antibiotic effectiveness. NHS costs per child were slightly higher (antibiotics, £29; placebo, £26), with no difference in non-NHS costs (antibiotics, £33; placebo, £33). A model predicting complications (with seven variables: baseline severity, difference in respiratory rate from normal for age, duration of prior illness, oxygen saturation, sputum/rattly chest, passing urine less often, and diarrhoea) had good discrimination (bootstrapped area under the receiver operator curve 0.83) and calibration. Parents found it difficult to interpret symptoms and signs, used the sounds of the child's cough to judge the severity of illness, and commonly consulted to receive a clinical examination and reassurance. Parents acknowledged that antibiotics should be used only when 'necessary', and clinicians noted a reduction in parents' expectations for antibiotics.

Limitations

The study was underpowered to detect small benefits in key subgroups.

Conclusion

Amoxicillin for uncomplicated lower respiratory tract infections in children is unlikely to be clinically effective or to reduce health or societal costs. Parents need better access to information, as well as clear communication about the self-management of their child's illness and safety-netting.

Future work

The data can be incorporated in the Cochrane review and individual patient data meta-analysis.

Trial registration

This trial is registered as ISRCTN79914298.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 9. See the NIHR Journals Library website for further project information.

The dawn of repurposing vitamins as potential novel antimicrobial agents: A call for global emergency response amidst AMR crisis

Amidst, the global pandemic of antimicrobial resistance (AMR), the rate at which AMR increases overwhelms the increased efforts to discover new effective antimicrobials. There is a persistent need for alternative treatment modalities so as to keep up with the pace. AMR is the leading cause of death in the world and its health and economic consequences suggest the urgent need for sustainable interventions. Vitamins have consistently proven to have antimicrobial activity as well as slowing down the AMR rate by influencing the AMR genes even towards extensive multidrug resistant strains. Evidences suggest that the use of some vitamins on their own or in combination with existing antimicrobial agents could be a breakthrough towards combating AMR. This will widen the antimicrobial agents' options in the treatment arena, preserve the antimicrobial agents susceptible to develop resistant so that they can be used in severe infections only, reduce the tension and burden of the AMR crisis significantly and give enough room for development of new antimicrobial agents. Moreover, almost all viral, fungal, parasitic and bacterial resistant strains of concern as listed by World Health Organization have been found to be sensitive to several vitamins either synergistically with other antimicrobials or independently. Considering their widened spectrum of immunomodulatory and antimicrobial effect, some vitamins can further be repositioned as prophylactic antimicrobial agents in clinical situations like in presurgeries prophylaxis so as to avoid unnecessary use of antimicrobials especially antibiotics. Various relevant AMR stakeholders should invest in clinical trials and systematic reviews with available data to enable quick repositioning of some potential vitamins as antimicrobial agents as an emergency rapid response towards AMR Crisis. This includes the preparation of guidelines containing specificity of which vitamin to be used for treatment of which type of infection.

Quality improvement: Antimicrobial stewardship in pediatric primary care

BACKGROUND

Antimicrobial resistance is the resistance of microorganisms to antibacterial, antiviral, antiparasitic, and antifungal medication resulting in increased healthcare costs with extended hospital stays in the United States. The goals of this quality improvement project were to increase the understanding and importance of antimicrobial stewardship by nurses and health care staff and increase pediatric parents'/guardians' knowledge of the proper use of antibiotics and differences between viruses and bacterial infections.

METHODS

A retrospective pre-post study was conducted in a midwestern clinic to determine if an antimicrobial stewardship teaching leaflet increased parent/guardian antimicrobial stewardship knowledge. The two interventions for patient education were a modified United States Center for Disease Control antimicrobial stewardship teaching leaflet and a poster regarding antimicrobial stewardship.

RESULTS

Seventy-six parents/guardians participated in the pre-intervention survey, with 56 being included in the post-intervention survey. There was a significant increase in knowledge between the pre-intervention survey and the post-intervention survey with a large effect size, p < .001, d = 0.86. This effect was also seen when comparing parents/guardians with no college education, who had a mean knowledge increased change score of 0.62, to those parents/guardians with a college education, whose mean knowledge increase was 0.23, p < .001 with a large effect size of 0.81. Health care staff thought the antimicrobial stewardship teaching leaflets and posters were beneficial.

PRACTICE IMPLICATIONS

The use of an antimicrobial stewardship teaching leaflet and a patient education poster may be effective interventions for improving healthcare staff's and pediatric parents'/guardians' knowledge of antimicrobial stewardship.

Implementation of a Clinical Protocol to Reduce Urinary Tract Infections Among Women With Urinary Retention After Pelvic Reconstructive Surgery: A Prospective Quality Improvement Study

OBJECTIVE

We implemented and assessed a clinical practice quality improvement protocol aimed at decreasing postoperative urinary tract infections (UTIs) among patients with transurethral catheters.

METHODS

This was a quality improvement study with pre- and post-intervention comparisons. Patients requiring postoperative transurethral catheters underwent 3 interventions: (1) shortening the time from surgery to repeat voiding trials to 3-5 days for pelvic reconstructive surgeries and to 1-3 days for mid-urethral slings, (2) avoiding routine urine cultures at the time of voiding trials, and (3) recommending 2 L of water intake daily until 3 days after the voiding trial. The primary outcome was the percentage of patients receiving antibiotics for UTIs within 6 weeks. Secondary outcomes included rates of failing office voiding trials, UTI symptoms/cultures, adherence to hydration, and health care resource utilization.

RESULTS

We included 31 patients before and 40 patients after the intervention. The 2 cohorts had similar demographic and clinical characteristics. Among patients requiring catheterization, rates of antibiotic treatment for UTIs decreased from 65% to 40% after the intervention (P = 0.04). UTI symptoms and urine cultures sent for analysis decreased significantly (P = 0.04 and P = 0.005, respectively). There was high adherence (84%) to increased hydration. Rates of failing office voiding trials remained similar. The number of phone calls decreased by 43% (P = 0.003), and there was no increase in office or emergency department visits. Multivariate regression showed that UTIs were 2.04 times more likely before than after the intervention.

CONCLUSION

Our quality improvement intervention was practical to implement and effective in reducing postoperative UTIs among patients with urinary catheters.

Antibiotic review kit for hospitals (ARK-Hospital): a stepped-wedge cluster-randomised controlled trial

BACKGROUND

Strategies to reduce antibiotic overuse in hospitals depend on prescribers taking decisions to stop unnecessary antibiotic use. There is scarce evidence for how to support these decisions. We evaluated a multifaceted behaviour change intervention (ie, the antibiotic review kit) designed to reduce antibiotic use among adult acute general medical inpatients by increasing appropriate decisions to stop antibiotics at clinical review.

METHODS

We performed a stepped-wedge, cluster (hospital)-randomised controlled trial using computer-generated sequence randomisation of eligible hospitals in seven calendar-time blocks in the UK. Hospitals were eligible for inclusion if they admitted adult non-elective general or medical inpatients, had a local representative to champion the intervention, and could provide the required study data. Hospital clusters were randomised to an implementation date occurring at 1-2 week intervals, and the date was concealed until 12 weeks before implementation, when local preparations were designed to start. The intervention effect was assessed using data from pseudonymised routine electronic health records, ward-level antibiotic dispensing, Clostridioides difficile tests, prescription audits, and an implementation process evaluation. Co-primary outcomes were monthly antibiotic defined daily doses per adult acute general medical admission (hospital-level, superiority) and all-cause mortality within 30 days of admission (patient level, non-inferiority margin of 5%). Outcomes were assessed in the modified intention-to-treat population (ie, excluding sites that withdrew before implementation). Intervention effects were assessed by use of interrupted time series analyses within each site, estimating overall effects through random-effects meta-analysis, with heterogeneity across prespecified potential modifiers assessed by use of meta-regression. This trial is completed and is registered with ISRCTN, ISRCTN12674243.

FINDINGS

58 hospital organisations expressed an interest in participating. Three pilot sites implemented the intervention between Sept 25 and Nov 20, 2017. 43 further sites were randomised to implement the intervention between Feb 12, 2018, and July 1, 2019, and seven sites withdrew before implementation. 39 sites were followed up for at least 14 months. Adjusted estimates showed reductions in total antibiotic defined daily doses per acute general medical admission (-4·8% per year, 95% CI -9·1 to -0·2) following the intervention. Among 7 160 421 acute general medical admissions, the ARK intervention was associated with an immediate change of -2·7% (95% CI -5·7 to 0·3) and sustained change of 3·0% (-0·1 to 6·2) in adjusted 30-day mortality.

INTERPRETATION

The antibiotic review kit intervention resulted in sustained reductions in antibiotic use among adult acute general medical inpatients. The weak, inconsistent intervention effects on mortality are probably explained by the onset of the COVID-19 pandemic. Hospitals should use the antibiotic review kit to reduce antibiotic overuse.

FUNDING

UK National Institute for Health and Care Research.

Das gute Leben heute und morgen: Antibiotikaresistente Keime als Nachhaltigkeitsproblem in der Medizin

In einem ersten Kapitel wird am Beispiel der Entstehung von Antibiotikaresistenzen gezeigt, dass es in der Medizin spezifische Nachhaltigkeitsprobleme gibt, die letztlich zu einer Beeinträchtigung der Fähigkeit zukünftiger Patient:innen führen können, ihre Gesundheitsbedürfnisse zu befriedigen und ein gutes Leben zu leben. Nachdem in einem zweiten Kapitel auf den Nachhaltigkeitsbegriff genauer eingegangen wurde, wird im dritten Teil erläutert, dass und warum die Möglichkeit zur Befriedigung elementarer Gesundheitsbedürfnisse z. B. im Rahmen eines Capability-Ansatzes zu Recht als eine Bedingung für ein gutes Leben gilt. Das Konzept der Nachhaltigkeit der Vereinten Nationen fordert, die Ansprüche auf ein gutes Leben zukünftiger Patient:innen angemessen zu berücksichtigen. Im vierten Teil wird dargestellt, wie Nachhaltigkeitsforderungen im klinischen Kontext zu einem Nachhaltigkeits-Dilemma führen können, und geklärt, auf welche Weise mit diesem Dilemma umgegangen werden kann.

Electric Spark Deposition of Antibacterial Silver Coating on Microstructured Titanium Surfaces with a Novel Flexible Brush Electrode

Infection caused by orthopedic titanium implants, which results in tissue damage, is a key factor in endosseous implant failure. Given the seriousness of implant infections and the limitations of antibiotic therapy, surface microstructures and antimicrobial silver coatings have emerged as prominent research areas and have displayed certain antimicrobial effects. Researchers are now working to combine the two to produce more effective antimicrobial surfaces. However, building robust and homogeneous coatings on complex microstructured surfaces is a tough task due to the limits of surface modification techniques. In this study, a novel flexible electrode brush (silver brush) instead of a traditional hard electrode was designed with electrical discharge machining, which has the ability to adapt to complex groove interiors. The results showed that the use of flexible electrode brush allowed silver to be deposited uniformly in titanium alloy microgrooves. On the surface of Ag-TC4, a uniformly covered deposit was visible, and it slowly released silver ions into a liquid environment. In vitro bacterial assays showed that a Ag-TC4 microstructured surface reduced bacterial adhesion and bacterial biofilm formation, and the antibacterial activity of Ag-TC4 against Staphylococcus aureus and Escherichia coli was 99.68% ± 0.002 and 99.50% ± 0.007, respectively. This research could lay the groundwork for the study of antimicrobial metal bound to microstructured surfaces and pave the way for future implant surface design.

Anti-Infective Secondary Metabolites of the Marine Cyanobacterium Lyngbya Morphotype between 1979 and 2022

Cyanobacteria ascribed to the genus Lyngbya (Family Oscillatoriaceae) represent a potential therapeutic gold mine of chemically and biologically diverse natural products that exhibit a wide array of biological properties. Phylogenetic analyses have established the Lyngbya 'morpho-type' as a highly polyphyletic group and have resulted in taxonomic revision and description of an additional six new cyanobacterial genera in the same family to date. Among the most prolific marine cyanobacterial producers of biologically active compounds are the species Moorena producens (previously L. majuscula, then Moorea producens), M. bouillonii (previously L. bouillonii), and L. confervoides. Over the years, compounding evidence from in vitro and in vivo studies in support of the significant pharmaceutical potential of 'Lyngbya'-derived natural products has made the Lyngbya morphotype a significant target for biomedical research and novel drug leads development. This comprehensive review covers compounds with reported anti-infective activities through 2022 from the Lyngbya morphotype, including new genera arising from recent phylogenetic re-classification. So far, 72 anti-infective secondary metabolites have been isolated from various Dapis, Lyngbya, Moorea, and Okeania species. These compounds showed significant antibacterial, antiparasitic, antifungal, antiviral and molluscicidal effects. Herein, a comprehensive literature review covering the natural source, chemical structure, and biological/pharmacological properties will be presented.

Evaluating the impact of Respiratory Syncytial Virus immunisation strategies on antibiotic use and drug resistant bacterial infections in England

Background: Vaccines against viruses have been proposed as a novel means to reduce antibiotic use, which would, in turn, decrease selection for antibiotic resistant bacteria. However, the impact of this intervention is poorly quantified, and likely depends on setting-specific epidemiology. Therefore, with increasing confidence in a new vaccine against respiratory syncytial virus (RSV), it is important to quantify the impact of these vaccines on antibiotic prescribing and any downstream reduction in drug resistant bacterial infections. Methods: Here we integrate results from a dynamic transmission model of RSV and a statistical attribution framework to capture the impact of RSV vaccines on the reduction in antibiotic prescribing due to averted primary care visits in England. Results: Under base case assumptions, we find that the most impactful RSV vaccine strategy targets children aged 5–14 years, resulting in an annual reduction of 10.9 (8.0–14.2) antibiotic courses per 10,000 person years across the entire population, equivalent to reducing annual all-cause primary care prescribing by 0.23%. Our results suggest that this reduction in antibiotic use would gain 130 disability-adjusted life years and avert £51,000 associated with drug resistant bacterial infections. Seasonally administering monoclonal antibodies (mAbs) to high-risk infants under 6 months is the most efficient strategy, reducing per person year antibiotic prescribing by 2.6 (1.9–3.3) antibiotic courses per 1,000 mAb courses. Conclusions: Under optimistic conditions, the cost-effectiveness of RSV vaccine strategies in England would likely not be altered by integrating the benefits of preventing drug resistant infections in addition to RSV disease prevention.

Bactericidal Efficacy of Nanostructured Surfaces Increases under Flow Conditions

Bacterial colonization on solid surfaces creates enormous problems across various industries causing billions of dollars' worth of economic damages and costing human lives. Biomimicking nanostructured surfaces have demonstrated a promising future in mitigating bacterial colonization and related issues. The importance of this non-chemical method has been elevated due to bacterial evolvement into antibiotic and antiseptic-resistant strains. However, bacterial attachment and viability on nanostructured surfaces under fluid flow conditions has not been investigated thoroughly. In this study, attachment and viability of Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) on a model nanostructured surface were studied under fluid flow conditions. A wide range of flow rates resulting in a broad spectrum of fluid wall shear stress on a nanostructured surface representing various application conditions were experimentally investigated. The bacterial suspension was pumped through a custom-designed microfluidic device (MFD) that contains a sterile Ti-6Al-4V substrate. The surface of the titanium substrate was modified using a hydrothermal synthesis process to fabricate the nanowire structure on the surface. The results of the current study show that the fluid flow significantly reduces bacterial adhesion onto nanostructured surfaces and significantly reduces the viability of adherent cells. Interestingly, the bactericidal efficacy of the nanostructured surface was increased under the flow by ∼1.5-fold against P. aeruginosa and ∼3-fold against S. aureus under static conditions. The bactericidal efficacy had no dependency on the fluid wall shear stress level. However, trends in the dead-cell count with the fluid wall shear were slightly different between the two species. These findings will be highly useful in developing and optimizing nanostructures in the laboratory as well as translating them into successful industrial applications. These findings may be used to develop antibacterial surfaces on biomedical equipment such as catheters and vascular stents or industrial applications such as ship hulls and pipelines where bacterial colonization is a great challenge.

Modelling the cost-effectiveness of pulse oximetry in primary care management of acute respiratory infection in rural northern Thailand

OBJECTIVES

We aimed to determine the cost-effectiveness of supplementing standard care with pulse oximetry among children <5 years with acute respiratory infection (ARI) presenting to 32 primary care units in a rural district (total population 241,436) of Chiang Rai province, Thailand, and to assess the economic effects of extending pulse oximetry to older patients with ARI in this setting.

METHODS

We performed a model-based cost-effectiveness analysis from a health systems perspective. Decision trees were constructed for three patient categories (children <5 years, children 5-14 years, and adults), with a 1-year time horizon. Model parameters were based on data from 49,958 patients included in a review of acute infection management in the 32 primary care units, published studies, and procurement price lists. Parameters were varied in deterministic sensitivity analyses. Costs were expressed in 2021 US dollars with a willingness-to-pay threshold per DALY averted of $8624.

RESULTS

The annual direct cost of pulse oximetry, associated staff, training, and monitoring was $24,243. It reduced deaths from severe lower respiratory tract infections in children <5 years by 0.19 per 100,000 patients annually. In our population of 14,075 children <5 years, this was equivalent to 2.0 DALYs averted per year. When downstream costs such as those related to hospitalisation and inappropriate antibiotic prescription were considered, pulse oximetry dominated standard care, saving $12,757 annually. This intervention yielded smaller mortality gains in older patients but resulted in further cost savings, primarily by reducing inappropriate antibiotic prescriptions in these age groups. The dominance of the intervention was also demonstrated in all sensitivity analyses.

CONCLUSIONS

Pulse oximetry is a life-saving, cost-effective adjunct in ARI primary care management in rural northern Thailand. This finding is likely to be generalisable to neighbouring countries with similar disease epidemiology and health systems.

A national, multicentre web-based point prevalence survey of antimicrobial use in community healthcare centres across South Africa and the implications

OBJECTIVE

Up to 90% of antimicrobials globally are prescribed and dispensed in ambulatory care. However, there are considerable gaps regarding the extent and rationale for their use especially in low- and middle-income countries such as South Africa. Point prevalent surveys (PPS) are useful to determine current prescribing patterns, identify targets for quality improvement and evaluate the effectiveness of antimicrobial stewardship programmes (ASPs) within institutions. Consequently, the objective of this study was to undertake a PPS within community healthcare centers (CHCs) in South Africa given their importance to the public healthcare system. The findings will be used to provide guidance on future interventions to improve antimicrobial use in South Africa and wider.

METHODS

A PPS of antimicrobial consumption was undertaken among patients attending 18 CHCs in South Africa. A web-based application was used to record the utilization data, with utilization assessed against World Health Organization (WHO) and South African guidelines.

RESULTS

The overall prevalence of antimicrobial use amongst patients attending the CHCs was 21.5% (420 of 1958 patients). This included one or more antimicrobials per patient. The most frequently prescribed antimicrobials were amoxicillin (32.9%), isoniazide (11.3%) and a combination of rifampicin, isoniazid, pyrazinamide and ethambutol (Rifafour®) (10.5%), with the majority from the WHO Access list of antibiotics. There was high adherence to guidelines (93.4%). The most common indication for antibiotics were ear, nose and throat infections (22.8%), with no culture results recorded in patients' files.

CONCLUSIONS

It's encouraging to see high adherence to South African guidelines when antimicrobials were prescribed, with the majority taken from the WHO Access list. However, there were concerns with appreciable prescribing of antimicrobials for upper respiratory tract infections that are essentially viral in origin, and a lack of microbiological testing. The establishment of ASPs can help address identified concerns through designing and implementing appropriate interventions.

Faecal Carriage of Carbapenem-Resistant Acinetobacter baumannii: Comparison to Clinical Isolates from the Same Period (2017-2019)

Increasing prevalence of A. baumannii was found in the faecal samples of inpatients without infection caused by A. baumannii (0.15%; 55/7806). The aim of the study was to determine whether there is a relationship between the clinical strains and the increased faecal occurrence. Characteristics of faecal and clinical isolates were compared between 2017 and 2019, and the direction of causality was assessed by Granger causality tests. In the case of the antibiotic resistance, faecal carriage of carbapenem-resistant Acinetobacter baumannii (CRAb) was Granger-caused by prevalence of CRAb in inpatients (F = 15.84, p < 0.001), but inpatient prevalence was not Granger-caused by CRAb faecal carriage (F = 0.03, p = 0.855). Whole genomes of 16 faecal isolates were sequenced by Illumina MiSeq; cgMLST types were determined. In faecal isolates, the occurrence of carbapenem resistance was lower than among the clinical isolates from the same period; only blaOXA-72 harbouring ST636 and ST492 were detected, and the blaOXA-23 harbouring ST2 and ST49 strains previously dominant in clinical isolates were absent. Carriage of blaOXA-72 was linked to pMAL-1-like and pA105-2-like plasmids in ST636 and ST492 isolates, respectively, both in clinical and faecal isolates. The new ST636 and ST492 strains may colonise the gut microbiota of the patients, which thus may play a role as a reservoir.

Survey on antimicrobial resistance knowledge and perceptions in university students reveals concerning trends on antibiotic use and procurement

BACKGROUND

The World Health Organization (WHO) has declared that antimicrobial resistance is one of the top ten global public health threats humanity is facing. To tackle this problem, it is necessary to not only address it in the hospital setting, but even more so in the community. In this context, understanding people's knowledge, attitudes, and practices towards antimicrobial resistance is of utmost importance. Accordingly, we investigated whether students from the Université de Montréal (Quebec, Canada) had perceptions and behaviours that could foster bacterial resistance.

METHODS

We conducted an observational, cross-sectional, prospective, and descriptive study from November 30 to December 11, 2020. We applied an online questionnaire (Google Forms) adapted from the WHO survey entitled 'Antibiotic resistance: Multi-country public awareness survey.'

RESULTS

Overall, 106 participants were included in this study. Most of them demonstrated reasonable understanding and behaviours related to antimicrobial resistance. Erroneous response proportions ranged from 0.9% to 25.5%, except for the statement 'Antibiotic resistance occurs when your body becomes resistant to antibiotics, and they no longer work,' where 63.2% of participants answered that it was true, even though it is false. Regarding antibiotic use, 28.3% of participants said they already had used antibiotics without a doctor's prescription. Of these, 55.2% were Canadian students.

CONCLUSIONS

This study indicates a possible misuse of antimicrobials in an area where antibiotics should not be easily accessible without a prescription. It is necessary to investigate why these medications are being used without being prescribed. Furthermore, we demonstrate a need to increase public awareness to better understand antimicrobial resistance's theoretical basis.

Impact of therapeutic drug monitoring of antibiotics in the management of infective endocarditis

Treatment of infective endocarditis (IE) is based on high doses of antibiotics with a prolonged duration. Therapeutic drug monitoring (TDM) allows antibiotic prescription optimization and leads to a personalized medicine, but no study evaluates its interest in the management of IE. We conducted a retrospective, bicentric, descriptive study, from January 2007 to December 2019. We included patients cared for IE, defined according to Duke's criteria, for whom a TDM was requested. Clinical and microbiological data were collected after patients' charts review. We considered a trough or steady-state concentration target of 20 to 50 mg/L. We included 322 IE episodes, corresponding to 306 patients, with 78.6% (253/326) were considered definite according to Duke's criteria. Native valves were involved in 60.5% (185/306) with aortic valve in 46.6% (150/322) and mitral in 36.3% (117/322). Echocardiography was positive in 76.7% (247/322) of cases. After TDM, a dosage modification was performed in 51.5% (166/322) (decrease in 84.3% (140/166)). After initial dosage, 46.3% (82/177) and 92.8% (52/56) were considered overdosed, when amoxicillin and cloxacillin were used, respectively. The length of hospital stay was higher for patient overdosed (25 days versus 20 days (p = 0.04)), and altered creatinine clearance was associated with overdosage (p = 0.01). Our study suggests that the use of current guidelines probably leads to unnecessarily high concentrations in most patients. TDM benefits predominate in patients with altered renal function, but probably limit adverse effects related to overdosing in most patients.

Medicinal Chemistry of Inhibitors Targeting Resistant Bacteria

The discovery of antibiotics was a revolutionary feat that provided countless health benefits. The identification of penicillin by Alexander Fleming initiated the era of antibiotics, represented by constant discoveries that enabled effective treatments for the different classes of diseases caused by bacteria. However, the indiscriminate use of these drugs allowed the emergence of resistance mechanisms of these microorganisms against the available drugs. In addition, the constant discoveries in the 20th century generated a shortage of new molecules, worrying health agencies and professionals about the appearance of multidrug-resistant strains against available drugs. In this context, the advances of recent years in molecular biology and microbiology have allowed new perspectives in drug design and development, using the findings related to the mechanisms of bacterial resistance to generate new drugs that are not affected by such mechanisms and supply new molecules to be used to treat resistant bacterial infections. Besides, a promising strategy against bacterial resistance is the combination of drugs through adjuvants, providing new expectations in designing new antibiotics and new antimicrobial therapies. Thus, this manuscript will address the main mechanisms of bacterial resistance under the understanding of medicinal chemistry, showing the main active compounds against efflux mechanisms, and also the application of the use of drug delivery systems, and finally, the main potential natural products as adjuvants or with promising activity against resistant strains.

Antibiotic prophylaxis at the time of dental implant placement: a cost-effectiveness analysis

Background

Antibiotic prophylaxis during implant placement may improve implant short term survival. Nevertheless, use of antibiotics carries risks of adverse effects and antibiotic resistance. The aim of the present study is to compare the use of antibiotics in dental implant procedures in terms of costs and effectiveness.

Methods

A decision-tree model was developed using TreeAge Pro Healthcare software. Two strategies were compared: Antibiotics and No antibiotics in implant placement procedures. The costs were calculated considering direct costs for implant placement, antibiotic costs, and costs for implant replacement in case of failure. Effectiveness was defined in terms of General Oral Health Assessment Index. Outcomes were evaluated as Incremental Cost Effectiveness Ratio (ICER). One-way sensitivity analysis and Probabilistic Sensitivity Analysis were performed for the most influential variables to test parameter uncertainty. Patient and healthcare perspectives were considered.

Results

Antibiotic prophylaxis resulted to be cost-effective compared to no use of antibiotics (ICER = 14,692,64 and ICER = 3841,18, respectively for patient’s and healthcare perspective). The cost of antibiotics, cost of implant replacement in case of failure and probability of adverse effects significantly influenced the results.

Conclusions

From an individual patient perspective, antibiotic strategy can be considered cost-effective, even when the cost of antibiotic therapy increases. We can conclude that the administration of antibiotics in association with implant placement is recommended in clinical practice, as it increases the success rate and makes the treatment more effective. However, attention should be placed when healthcare perspective is considered, particularly in terms of antibiotic resistance that may impact public health and associated costs.

Tackling antimicrobial resistance across sub-Saharan Africa: current challenges and implications for the future

INTRODUCTION

Antimicrobial resistance (AMR) is a concern as this increases morbidity, mortality, and costs, with sub-Saharan Africa having the highest rates globally. Concerns with rising AMR have resulted in international, Pan-African, and country activities including the development of national action plans (NAPs). However, there is variable implementation across Africa with key challenges persisting.

AREAS COVERED

Consequently, there is an urgent need to document current NAP activities and challenges across sub-Saharan Africa to provide future guidance. This builds on a narrative review of the literature.

EXPERT OPINION

All surveyed sub-Saharan African countries have developed their NAPs; however, there is variable implementation. Countries including Botswana and Namibia are yet to officially launch their NAPs with Eswatini only recently launching its NAP. Cameroon is further ahead with its NAP than these countries; though there are concerns with implementation. South Africa appears to have made the greatest strides with implementing its NAP including regular monitoring of activities and instigation of antimicrobial stewardship programs. Key challenges remain across Africa. These include available personnel, expertise, capacity, and resources to undertake agreed NAP activities including active surveillance, lack of focal points to drive NAPs, and competing demands and priorities including among donors. These challenges are being addressed, with further co-ordinated efforts needed to reduce AMR.

Antimicrobial resistance patterns in bacteria causing febrile illness in Africa, South Asia, and Southeast Asia: a systematic review of published etiological studies from 1980-2015

OBJECTIVE

In this study, we aimed to conduct a systematic review to characterize antimicrobial resistance (AMR) patterns for bacterial causes of febrile illness in Africa and Asia.

METHODS

We included published literature from 1980-2015 based on data extracted from two recent systematic reviews of nonmalarial febrile illness from Africa, South Asia, and Southeast Asia. Selection criteria included articles with full bacterial identification and antimicrobial susceptibility testing (AST) results for key normally sterile site pathogen-drug combinations. Pooled proportions of resistant isolates were combined using random effects meta-analysis. Study data quality was graded using the Microbiology Investigation Criteria for Reporting Objectively (MICRO) framework.

RESULTS

Of 3475 unique articles included in the previous reviews, 371 included the target pathogen-drug combinations. Salmonella enterica tested against ceftriaxone and ciprofloxacin were the two highest reported combinations (30,509 and 22,056 isolates, respectively). Pooled proportions of resistant isolates were high for third-generation cephalosporins for Klebsiella pneumoniae and Escherichia coli in all regions. The MICRO grading showed an overall lack of standardization.

CONCLUSION

This review highlights a general increase in AMR reporting and in resistance over time. However, there were substantial problems with diagnostic microbiological data quality. Urgent strengthening of laboratory capacity, standardized testing, and reporting of AST results is required to improve AMR surveillance.

Microbiological Profile and Drug Resistance Analysis of Postoperative Infections following Orthopedic Surgery: A 5-Year Retrospective Review

Background

The distribution of postoperative orthopedic infection and their susceptibility pattern to antibiotics vary regionally and change over time. The incidence of methicillin-resistant Staphylococcus aureus infection is rising worldwide. Therefore, knowledge of the frequency of the causative microorganisms and their susceptibility to antibiotics are necessary for an improved therapeutic outcome. This study aims to study the frequency and distribution of postoperative orthopedic infection and their resistance pattern to antibiotics.

Methods

The study utilized a retrospective design that took place over a period of 5 years from 2016 and 2020 at a tertiary care hospital. The bacterial culture testing was performed by a recommended method. Descriptive statistics were used to analyze the data.

Results

A total of 158 patients (100 males and 58 females) with positive cultures of postoperative orthopedic infection were included. The most common infective organism was Staphylococcus aureus, 64 patients (38.1%); coagulase-negative staphylococci, 40 patients (23.8%); Klebsiella species, 14 patients (8.3%); and Enterococcus species, Escherichia coli, and Pseudomonas aeruginosa in 10 patients (6%). Data also showed that gram-positive bacteria were detected in 118 patients (70.8%), while gram-negative microorganisms were found in 50 patients (29.8%). Among Staphylococcus aureus, 79.7% were MRSA, and vancomycin was the most effective antibiotic in staphylococcus infections. The antibiotics with the greatest sensitivity to gram-positive bacteria were vancomycin, linezolid, tigecycline, moxifloxacin, and nitrofurantoin, while the antibiotics for gram-negative bacteria with greater sensitivity were tigecycline, amikacin, ertapenem, imipenem, and cefotaxime.

Conclusion

Staphylococcus aureus is the most common postoperative orthopedic infection, which was predominantly MRSA with vancomycin being the most effective antibiotic. In addition, the results showed a high resistance pattern to the commonly used antibiotics, leaving few choices. Antibiotic agents should be carefully selected according to specific drug sensitivity through routine monitoring of drug resistance patterns and to help formulate hospital antibiotic policy.

Economic evaluation of antimicrobial stewardship in primary care: a systematic review and quality assessment

Background

Primary care accounts for 80%–90% of antimicrobial prescriptions, making this setting an important focus for antimicrobial stewardship (AMS) interventions.

Objectives

To collate the findings and critically appraise the qualities of economic evaluation studies of AMS or related interventions aimed at reducing inappropriate antimicrobial prescribing in primary care.

Methods

A systematic review of economic evaluations of interventions aimed at reducing inappropriate antimicrobial prescribing in primary care was performed. Published literature were retrieved through a search of Medline, Embase, EconLit and Web of Science databases for the period 2010 to 2020. The quality of the studies was assessed using the Consensus on Health Economic Criteria checklist and Good Practice Guidelines for Decision-Analytic Modelling in Health Technology Assessment.

Results

Of the 2722 records identified, 12 studies were included in the review (8 trial-based and 4 modelled evaluations). The most common AMS interventions were communication skills training for health professionals and C-reactive protein point-of-care testing (CRP-POCT). Types of economic evaluations included in the review were cost-effectiveness (7 studies), cost-utility (1), cost-benefit (2), cost-effectiveness and cost-utility (1) and cost analysis (1). While six of the studies found AMS interventions to be cost-effective, the other six reported them as not cost-effective or inconclusive. The quality of the studies ranged from good to low.

Conclusions

There were significant variations in cost-effectiveness of AMS interventions across studies and depending on the inclusion of cost components such as the cost of antimicrobial resistance. However, communication skills training and CRP-POCT were frequently cost-effective or cost-beneficial for reducing inappropriate antimicrobial prescribing.

Marine Cyclic Peptides: Antimicrobial Activity and Synthetic Strategies

Oceans are a rich source of structurally unique bioactive compounds from the perspective of potential therapeutic agents. Marine peptides are a particularly interesting group of secondary metabolites because of their chemistry and wide range of biological activities. Among them, cyclic peptides exhibit a broad spectrum of antimicrobial activities, including against bacteria, protozoa, fungi, and viruses. Moreover, there are several examples of marine cyclic peptides revealing interesting antimicrobial activities against numerous drug-resistant bacteria and fungi, making these compounds a very promising resource in the search for novel antimicrobial agents to revert multidrug-resistance. This review summarizes 174 marine cyclic peptides with antibacterial, antifungal, antiparasitic, or antiviral properties. These natural products were categorized according to their sources—sponges, mollusks, crustaceans, crabs, marine bacteria, and fungi—and chemical structure—cyclic peptides and depsipeptides. The antimicrobial activities, including against drug-resistant microorganisms, unusual structural characteristics, and hits more advanced in (pre)clinical studies, are highlighted. Nocathiacins I–III (91–93), unnarmicins A (114) and C (115), sclerotides A (160) and B (161), and plitidepsin (174) can be highlighted considering not only their high antimicrobial potency in vitro, but also for their promising in vivo results. Marine cyclic peptides are also interesting models for molecular modifications and/or total synthesis to obtain more potent compounds, with improved properties and in higher quantity. Solid-phase Fmoc- and Boc-protection chemistry is the major synthetic strategy to obtain marine cyclic peptides with antimicrobial properties, and key examples are presented guiding microbiologist and medicinal chemists to the discovery of new antimicrobial drug candidates from marine sources.

Identification of metabolite extraction method for targeted exploration of antimicrobial resistance associated metabolites of Klebsiella pneumoniae

Antimicrobial resistant Klebsiella pneumoniae (K. pneumoniae), as being a pathogen of critical clinical concern, urgently demands effective therapeutic options. However, the discovery of novel antibiotics over the last three decades has declined drastically and necessitates exploring novel strategies. Metabolomic modulation has been the promising approach for the development of effective therapeutics to deal with AMR; however, only limited efforts have been made to-date, possibly due to the unavailability of suitable metabolites extraction protocols. Therefore, in order to establish a detailed metabolome of K. pneumoniae and identify a method for targeted exploration of metabolites that are involved in the regulation of AMR associated processes, metabolites were extracted using multiple methods of metabolites extraction (freeze-thaw cycle (FTC) and sonication cycle (SC) method alone or in combination (FTC followed by SC; FTC + SC)) from K. pneumoniae cells and then identified using an orbitrap mass analyzer (ESI-LC-MS/MS). A total of 151 metabolites were identified by using FTC, 132 metabolites by using FTC+SC, 103 metabolites by using SC and 69 metabolites common among all the methods used which altogether enabled the identification of 199 unique metabolites. Of these 199, 70 metabolites were known to have an association with AMR phenotype and among these, the FTC + SC method yielded better (identified 55 metabolites), quantitatively and qualitatively compared to FTC and SC alone (identified 51 and 41 metabolites respectively). Each method of metabolite extraction showed a definite degree of biasness and specificity towards chemical classes of metabolites and jointly contributed to the development of a detailed metabolome of the pathogen. FTC method was observed to give higher metabolomic coverage as compared to SC alone and FTC + SC. However, FTC + SC resulted in the identification of a higher number of AMR associated metabolites of K. pneumoniae compared to FTC and SC alone.