Clinical and economic burden of antimicrobial resistance

A pill for every ill? Unpacking antibiotic misuse among Bangladeshi university students

BACKGROUND

The misuse of antibiotics and the resulting emergence of antibiotic resistance in bacterial strains are both important global health issues worldwide, especially for developing countries including Bangladesh.

OBJECTIVE

The study investigated the antibiotic-seeking behaviour of Bangladeshi university students and the views of medical and public health experts on the harmful effects of antibiotic overuse on students.

METHOD

Forty in-depth students' interviews and 10 key informant interviews with medical and public health professionals were used to collect data using a qualitative study design and descriptive phenomenology research approach. Thematic analysis technique was conducted to analyse the collected data.

RESULTS

The study found university students frequently seek, ask for and consume antibiotics from pharmacies to recover quickly and reduce the time-cost-visit of treatment. In certain instances, medical practitioners recommend antibiotics as a general treatment approach to enhance their popularity among patients and expedite their recovery from illness. However, they are being led into protracted illness due to poor knowledge and excessive usage of antibiotics.

CONCLUSION

Students risk serious health issues by taking unnecessary antibiotics to recuperate quickly, which increases the nation's health burden. The study stresses the need for stricter restrictions and limiting antibiotic availability and intervention in educational, community and policy settings.

Antibacterial properties of quaternized cellulose nanocrystals in clinical isolates of multidrug-resistant gram-negative bacteria

Gram-negative bacterial pathogens are responsible for various infections. Over the past decade, these pathogens have acquired resistance to multiple antibiotics, and the multidrug-resistant (MDR) bacteria have rapidly spread globally, creating significant treatment challenges. Quaternized cellulose nanocrystals (CNCs) have promising antibacterial properties. We previously reported quaternized CNCs with ten-carbon (CNC-3) and sixteen-carbon (CNC-4) alkyl chains and an unmodified CNC (CNC-1). We found that CNC-4 exhibited a significant bactericidal effect against Staphylococcus aureus. In this study, we aim to evaluate the antibacterial properties of the quaternized CNCs against Gram-negative MDR clinical isolates of Acinetobacter baumannii (21 isolates), Klebsiella pneumoniae (18 isolates), and Escherichia coli (7 isolates), including each of their reference species. Agar diffusion, minimum bactericidal concentration (MBC), and bacterial killing pattern were conducted. The results showed that CNC-3 exhibited an MBC of 50 μg ml-1 for 28% (13 out of 46 isolates) and 100 μg ml-1 for 72% (33 out of 46 isolates), regardless of their antibiotic susceptibility. In comparison, CNC-4 exhibited an MBC of 100 μg ml-1 for 28% (5 out of 18 K. pneumoniae), while all other isolates and the reference species exhibited an MBC of >100 μg ml-1. For CNC-1, the MBC was >100 μg ml-1 for all tested isolates and the reference species. These results suggest that, unlike S. aureus, CNC-3 has a significantly higher and broader spectrum of bactericidal effects than CNC-4 against Gram-negative bacteria. This finding suggests that quaternized CNCs may be a potential antimicrobial agent for treating Gram-negative bacterial infections.

Oxirapentyn A, Derived from Marine Amphichorda felina, Effectively Inhibits Quorum Sensing and Biofilm Formation Against Chromobacterium violaceum

The emergence of multidrug-resistant Chromobacterium violaceum, an opportunistic pathogen, poses a significant threat to human, animal, and environmental health, underscoring the urgent need for innovative strategies. Marine-derived natural compounds have gained attention as a promising source of quorum sensing inhibitors (QSIs) that can attenuate C. violaceum virulence without inducing resistance. This study reports, for the first time, the anti-quorum sensing (anti-QS) and anti-biofilm activities of oxirapentyn A, one marine natural compound, against C. violaceum. Results demonstrate oxirapentyn A (200 μg/mL) significantly inhibits biofilm formation, violacein production, and hemolysin synthesis by 48.8, 21.7, and 22.3%, respectively. Scanning electron microscopy (SEM) further corroborated the disruption of biofilm architecture. LC-MS analysis revealed a concentration-dependent reduction in the production of N-decanoyl-homoserine lactone (C10-HSL), a key QS signaling molecule. Furthermore, RT-qPCR analysis indicated oxirapentyn A downregulated critical QS-related genes (cviI, cviR, vioA, chiA, and pykF) by 20.7, 36.6, 31.1, 66.6, and 30.7%, respectively. Notably, in vivo experiments demonstrated that oxirapentyn A significantly improved the survival of Galleria mellonella larvae infected with C. violaceum. Collectively, these findings highlight oxirapentyn A as a novel QSI with dual anti-QS and biofilm-disrupting activities, offering a promising strategy to combat drug-resistant bacterial infections.

MAPRS: An intelligent approach for post-prescription review based on multi-label learning

Antimicrobial resistance (AMR) is a major threat to public health worldwide. It is a promising way to improve appropriate prescription by the review and stewardship of antimicrobials, and Post-Prescription Review (PPR) is currently the main tool used in hospitals. Existing methods of PPR typically focus on the dichotomy of antimicrobial prescription based on binary classification which, however, is usually a multi-label classification problem. Moreover, previous research did not explain the causes beneath the inappropriate antimicrobial used in the clinical setting, which could be practically important for problem location and decision improvement. In this paper, we collected antimicrobial prescriptions and related data from clean surgery in a hospital in northeastern China, and proposed a Multi-label Antimicrobial Post-Prescription Review System (MAPRS). MAPRS first uses NLP techniques to process unstructured data in prescriptions and explores the value of clinical record text for solving medical problems. Then, Classifier Chains are used to deal with multi-label problems and fused with machine learning algorithms to construct a classifier. At last, a SHAP explanation module is introduced to explain the inappropriate prescriptions. The experimental results show that MAPRS could achieve great performance in a challenging six-category multi-label task, with a subset accuracy of 90.7 % and an average AUROC of 94.3 %. Our results can help hospitals to perform intelligent prescription review and improve the antimicrobial stewardship.

Navigating collateral sensitivity: insights into the mechanisms and applications of antibiotic resistance trade-offs

The swift rise of antibiotic resistance, coupled with limited new antibiotic discovery, presents a significant hurdle to global public health, demanding innovative therapeutic solutions. Recently, collateral sensitivity (CS), the phenomenon in which resistance to one antibiotic increases vulnerability to another, has come to light as a potential path forward in this attempt. Targeting either unidirectional or reciprocal CS holds promise for constraining the emergence of drug resistance and notably enhancing treatment outcomes. Typically, the alteration of bacterial physiology, such as bacterial membrane potential, expression of efflux pumps, cell wall structures, and endogenous enzymatic actions, are involved in evolved collateral sensitivity. In this review, we present a thorough overview of CS in antibiotic therapy, including its definition, importance, and underlying mechanisms. We describe how CS can be exploited to prevent the emergence of resistance and enhance the results of treatment, but we also discuss the challenges and restrictions that come with implementing this practice. Our review underscores the importance of continued exploration of CS mechanisms in the broad spectrum and clinical validation of therapeutic approaches, offering insights into its role as a valuable tool in combating antibiotic resistance.

Use of Antibiotics in Animal Agriculture: Implications for Pediatrics: Technical Report

Antimicrobial resistance is a global public health threat. Antimicrobial-resistant infections are on the rise and are associated with increased morbidity, mortality, and health care costs. Infants and children are affected by transmission of antimicrobial-resistant zoonotic pathogens through the food supply, direct contact with animals, environmental pathways, and contact with infected or colonized humans. Although the judicious use of antimicrobial agents is necessary for maintaining the health and welfare of humans and animals, it must be recognized that all use of antimicrobial agents exerts selective pressure that increases the risk of development of resistance. This report describes historical and recent use of antibiotics in animal agriculture, reviews the mechanisms of how such use contributes to development of resistance and can adversely affect child health, and discusses US initiatives to curb unnecessary use of antimicrobial agents in agriculture.

An Overview of the Recent Advances in Antimicrobial Resistance

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

Getting rapid diagnostic test data into the appropriate hands by leveraging pharmacy staff and a clinical surveillance platform: a case study from a US community hospital

OBJECTIVES

To outline the procedural implementation and optimization of rapid diagnostic test (RDT) results for bloodstream infections (BSIs) and to evaluate the combination of RDTs with real-time antimicrobial stewardship team (AST) support plus clinical surveillance platform (CSP) software on time to appropriate therapy in BSIs at a single health system.

METHODS

Blood culture reporting and communication were reported for four time periods: (i) a pre-BCID [BioFire® FilmArray® Blood Culture Identification (BCID) Panel] implementation period that consisted of literature review and blood culture notification procedure revision; (ii) a BCID implementation period that consisted of BCID implementation, real-time results notification via CSP, and creation of a treatment algorithm; (iii) a post-BCID implementation period; and (iv) a BCID2 implementation period. Time to appropriate therapy metrics was reported for the BCID2 time period.

RESULTS

The mean time from BCID2 result to administration of effective antibiotics was 1.2 h (range 0-7.9 h) and time to optimal therapy was 7.6 h (range 0-113.8 h) during the BCID2 Panel implementation period. When comparing time to optimal antibiotic administration among patients growing ceftriaxone-resistant Enterobacterales, the BCID2 Panel group (mean 2.8 h) was significantly faster than the post-BCID Panel group (17.7 h; P = 0.0041).

CONCLUSIONS

Challenges exist in communicating results to the appropriate personnel on the healthcare team who have the knowledge to act on these data and prescribe targeted therapy against the pathogen(s) identified. In this report, we outline the procedures for telephonic communication and CSP support that were implemented at our health system to distribute RDT data to individuals capable of assessing results, enabling timely optimization of antimicrobial therapy.

Ginkgolic Acid as a carbapenem synergist against KPC-2 positive Klebsiella pneumoniae

The successful evolution of KPC-2 in bacteria has limited the clinical practice of carbapenems. This dilemma deteriorated the prognosis of associated infections and hence attracted increasing attention from researchers to explore alternative therapeutic options. Here, the enzyme inhibition assay was first performed to screen for a potent KPC-2 inhibitor. The synergistic effect of the candidate with carbapenems was further confirmed by checkboard minimum inhibitory concentration (MIC) assay, time-killing assay, disk diffusion method, and live/dead bacteria staining analysis. The mechanisms by which the candidate acts were subsequently explored through molecular dynamics (MD) simulations, etc. Our study found that Ginkgolic Acid (C13:0) (GA) exhibited effective KPC-2 inhibitory activity in both laboratory strain and clinical strain containing KPC-2. It could potentiate the killing effect of carbapenems on KPC-2-positive Klebsiella pnenmoniae (K. pnenmoniae). Further explorations revealed that GA could competitively bind to the active pocket of KPC-2 with meropenem (MEM) via residues Trp104, Gly235, and Leu166. The secondary structure and functional groups of KPC-2 were subsequently altered, which may be the main mechanism by which GA exerted its KPC-2 inhibitory effect. In addition, GA was also found to synergize with MEM to disrupt membrane integrity and increase membrane permeability, which may be another mechanism by which GA reinforced the bactericidal ability of carbapenems. Our study indicated that GA was a significant KPC-2 inhibitor that could prolong the lifespan of carbapenems and improve the prognosis of patients.

28 NICUs participating in a quality improvement collaborative targeting early-onset sepsis antibiotic use

OBJECTIVE

There is widespread overuse of antibiotics in neonatal intensive care units (NICUs). The objective of this study was to safely reduce antibiotic use in participating NICUs by targeting early-onset sepsis (EOS) management.

STUDY DESIGN

Twenty-eight NICUs participated in this statewide multicenter antibiotic stewardship quality improvement collaborative. The primary aim was to reduce the total monthly mean antibiotic utilization rate (AUR) by 25% in participant NICUs.

RESULT

Aggregate AUR was reduced by 15.3% (p < 0.001). There was a wide range in improvement among participant NICUs. There were no increases in EOS rates or nosocomial infection rates related to the intervention.

CONCLUSION

Participation in this multicenter NICU antibiotic stewardship collaborative targeting EOS was associated with an aggregate reduction in antibiotic use. This study informs efforts aimed at sustaining improvements in NICU AURs.

Antibiotic Use Among Hospitalized Patients in Africa: A Systematic Review of Point Prevalence Studies

BACKGROUND

There is paucity of data describing the rate and quality indices of antibiotics used among hospitalized patients at continental level in Africa. This systematic review evaluated the pooled prevalence, indications, and types of antibiotics used in hospitals across Africa.

METHODS

Three electronic databases, PubMed, Scopus, and African Journals Online (AJOL), were searched using search terms. Point prevalence studies of antibiotic use in inpatient settings published in English language from January 2010 to November 2022 were considered for selection. Additional articles were identified by checking the reference list of selected articles.

RESULTS

Of the 7254 articles identified from the databases, 28 eligible articles involving 28 studies were selected. Most of the studies were from Nigeria (n = 9), Ghana (n = 6), and Kenya (n = 4). Overall, the prevalence of antibiotic use among hospitalized patients ranged from 27.6 to 83.5% with higher prevalence in West Africa (51.4-83.5%) and North Africa (79.1%) compared to East Africa (27.6-73.7%) and South Africa (33.6-49.7%). The ICU (64.4-100%; n = 9 studies) and the pediatric medical ward (10.6-94.6%; n = 13 studies) had the highest prevalence of antibiotic use. Community-acquired infections (27.7-61.0%; n = 19 studies) and surgical antibiotic prophylaxis (SAP) (14.6-45.3%; n = 17 studies) were the most common indications for antibiotic use. The duration of SAP was more than 1 day in 66.7 to 100% of the cases. The most commonly prescribed antibiotics included ceftriaxone (7.4-51.7%; n = 14 studies), metronidazole (14.6-44.8%; n = 12 studies), gentamicin (n = 8 studies; range: 6.6-22.3%), and ampicillin (n = 6 studies; range: 6.0-29.2%). The access, watch, and reserved group of antibiotics accounted for 46.3-97.9%, 1.8-53.5%, and 0.0-5.0% of antibiotic prescriptions, respectively. The documentation of the reason for antibiotic prescription and date for stop/review ranged from 37.3 to 100% and 19.6 to 100%, respectively.

CONCLUSION

The point prevalence of antibiotic use among hospitalized patients in Africa is relatively high and varied between the regions in the continent. The prevalence was higher in the ICU and pediatric medical ward compared to the other wards. Antibiotics were most commonly prescribed for community-acquired infections and for SAP with ceftriaxone, metronidazole, and gentamicin being the most common antibiotics prescribed. Antibiotic stewardship is recommended to address excessive use of SAP and to reduce high rate of antibiotic prescribing in the ICU and pediatric ward.

The experience of an antimicrobial stewardship program and antibiotic consumption and resistance trends during the COVID-19 pandemic at a tertiary care center in Beirut

BACKGROUND

Antimicrobial Resistance, a global concern, worsened with the COVID-19 pandemic that caused a surge of critically ill patients, increased antimicrobial consumption, and the spread of infections with multidrug-resistant organisms (MDROs). Antimicrobial Stewardship Programs (ASP) aim to optimize antimicrobial utilization to fight resistance. We aim to describe the ASP experience and to study antimicrobial consumption and MDRO rates among COVID-19 patients at a tertiary care center in Beirut.

METHODS

We compiled the ASP interventions, defined as ASP team recommendations, from January 2019 until December 2021. Data on antimicrobial consumption, expressed as a defined daily dose (DDD) per 100 patient days, was collected per quarter for all antimicrobials and restricted antimicrobials per ASP guidance. Our primary objective was to report on the ASP experience, and the secondary objective was to reflect on the rates of MDROs among hospitalized COVID-19 patients with respiratory or bloodstream bacterial co-infections between March 2020 and September 2021.

RESULTS

9922 ASP interventions were documented during this study period, with a noticeable correlation between COVID-19 surges in Lebanon and the number of ASP interventions. Acceptance rates for these recommendations improved over time, with a noticeable decrease in the proportion of interventions related to de-escalation and discontinuation of broad-spectrum antimicrobials. We noted an increase in all antimicrobial consumption after the onset of the pandemic, peaking in Q4 2020 (142.8 DDD of anti-infectives/100 patient days) and Q1 2021 (79.1 DDD of restricted anti-infectives/100 patient days). As expected, MDROs, particularly ESKAPE organisms (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Carbapenem-resistant Enterobacteriaceae) accounted for 24% of isolates obtained from this cohort.

CONCLUSION

This study highlights the experience of the ASP as we adapted to the COVID-19 pandemic. The ASP team maintained its operations and continued to monitor antibiotic consumption and provide recommendations to limit antibiotic misuse in an effort to mitigate the impact of the pandemic on antimicrobial resistance.

Knowledge and Attitude toward Antibiotic Use and Identification of Financially Feasible Options to Curb the Spread of Antibiotics in Environment

A survey on antibiotic literacy in terms of the use and abuse of antibiotics to track and understand antibiotic consumption is crucial to optimize the use of antibiotics and minimizing antimicrobial resistance (AMR). Purposive random sampling, using the snow-ball questionnaire technique, was adopted to ensure that the respondents distributed across India, coming from rural and urban settings, were adolescents as well as adults and had completed at least the higher secondary school level of education. Respondents were divided into five subcategories. The questionnaire was distributed between April 2021 and July 2021, during the second COVID-19 wave in India. The survey questionnaire included 34 questions, comprising multiple-choice and 5-point Likert scale-type questions. This study composed of 972 respondents. Most respondents considered antibiotics safe and frequently failed to discriminate between the symptoms of bacterial and viral infections, most often leading to self-prescription. About 34% of the rural participants and 50% of the urban participants considered antibiotic resistance a serious health concern. Antibiotic prescriptions by the medical or paramedical practitioner were largely empirical. At least 95% of participants acknowledged having heard about antibiotics; nearly 20% of antibiotic consumption came from nonprescription users, while 30% had not completed their antibiotic therapy for a variety of reasons. Sixty-two percent consumed antibiotics to treat cold and flu symptoms. Results from the survey suggest the presence of a crucial gap between the respondents' perception of antibiotics and levels of information regarding antibiotic use and misuse. The present study may serve as a benchmark that strongly recommends a financially feasible policy, which includes educating society regarding the spread of AMR and its severe consequences by incorporating AMR into the curriculum at the levels of senior secondary school and higher education.

Meningitis Risk and Role of Prophylactic Antibiotics in Spontaneous Lateral Skull Base CSF Leaks

OBJECTIVE

To review the literature and our institutional experience regarding the risk of meningitis in patients with spontaneous lateral skull base cerebrospinal fluid (sCSF) leaks awaiting surgical repair, and the roles of antibiotic prophylaxis and pneumococcal vaccination, if known.

METHODS

A retrospective chart review and systematic review of the literature was undertaken to identify the incidence of meningitis in patients with sCSF leaks awaiting surgical repair. Adults managed surgically for sCSF leaks at an academic tertiary care center over a 10-year period were included. Data was collected on receipt of prophylactic antibiotics and/or pneumococcal vaccines during the timeframe between diagnosis and surgical repair.

RESULTS

Institutional review identified 87 patients who underwent surgical repair of spontaneous leaks, with a 0% incidence of meningitis over a median duration of 2 months while awaiting surgery (mean 5.5 months, range 0.5-118 months). Eighty-eight percent of patients did not receive prophylactic antibiotics. No studies in the published literature demonstrated the impact of prophylactic antibiotics or pneumococcal vaccine on meningitis risk.

CONCLUSIONS

There appears to be a low risk of meningitis among patients with lateral skull base sCSF leaks awaiting surgery for short durations (≤2 months), even in the absence of prophylactic antibiotics. There is a substantial gap in the published literature assessing the risk of meningitis and roles of antibiotics and vaccination in this patient population, indicating the need for large-scale study to conclusively elucidate the nature of this risk.

Evaluation of Extended-Spectrum Beta-Lactamase Resistance in Uropathogenic Escherichia coli Isolates from Urinary Tract Infection Patients in Al-Baha, Saudi Arabia

Urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing organisms are prevalent in both outpatient and inpatient settings, representing the most often encountered forms of infection. This research aimed to estimate the prevalence of ESBL-UTIs along with other uropathogens in the adult population and to assess the antibiotic activity against Escherichia coli extended-spectrum beta-lactamase (E. coli ESBL) isolates from patient samples in Al-Baha. A retrospective cross-sectional study included patients who presented to King Fahad Hospital in Al-Baha with clinical suspicion of UTI between 1 January 2019 and 30 September 2022. A total of 4406 urine samples with significant microbial growth were included in the scope of this investigation. A collective count of 1644 incidents of Escherichia coli (E. coli) was observed, wherein E. coli constituted 85% of the cases, while the remaining 15% comprised E. coli ESBL producers. The prevalence of E. coli ESBL was observed to be 64.7% in females and 35.3% in males, with a majority (67%) of the affected individuals being over the age of 50. The incidence of E. coli infections in the outpatient setting was found to be greater than that observed in the inpatient setting. E. coli ESBL were sensitive to colistin, tigecycline, amikacin, meropenem, imipenem, and nitrofurantoin by 100% and 93.3-100%, 95-99.6%, 95-99.06%, and 81-91%, respectively. On the other hand, the most resistant agents for E. coli ESBL were the group of cephalosporins, aztreonam, and ampicillin with 100% resistance, ciprofloxacin with 56-74% resistance, and cotrimoxazole with a 45-53% resistance level. ESBL-resistant E. coli strains are moderately prevalent in community- and hospital-acquired UTIs, especially in females and elderly patients (>50 years).

Developing Phage Therapy That Overcomes the Evolution of Bacterial Resistance

The global rise of antibiotic resistance in bacterial pathogens and the waning efficacy of antibiotics urge consideration of alternative antimicrobial strategies. Phage therapy is a classic approach where bacteriophages (bacteria-specific viruses) are used against bacterial infections, with many recent successes in personalized medicine treatment of intractable infections. However, a perpetual challenge for developing generalized phage therapy is the expectation that viruses will exert selection for target bacteria to deploy defenses against virus attack, causing evolution of phage resistance during patient treatment. Here we review the two main complementary strategies for mitigating bacterial resistance in phage therapy: minimizing the ability for bacterial populations to evolve phage resistance and driving (steering) evolution of phage-resistant bacteria toward clinically favorable outcomes. We discuss future research directions that might further address the phage-resistance problem, to foster widespread development and deployment of therapeutic phage strategies that outsmart evolved bacterial resistance in clinical settings.

Recent Advances in Optical Sensing for the Detection of Microbial Contaminants

Microbial contaminants are responsible for several infectious diseases, and they have been introduced as important potential food- and water-borne risk factors. They become a global burden due to their health and safety threats. In addition, their tendency to undergo mutations that result in antimicrobial resistance makes them difficult to treat. In this respect, rapid and reliable detection of microbial contaminants carries great significance, and this research area is explored as a rich subject within a dynamic state. Optical sensing serving as analytical devices enables simple usage, low-cost, rapid, and sensitive detection with the advantage of their miniaturization. From the point of view of microbial contaminants, on-site detection plays a crucial role, and portable, easy-applicable, and effective point-of-care (POC) devices offer high specificity and sensitivity. They serve as advanced on-site detection tools and are pioneers in next-generation sensing platforms. In this review, recent trends and advances in optical sensing to detect microbial contaminants were mainly discussed. The most innovative and popular optical sensing approaches were highlighted, and different optical sensing methodologies were explained by emphasizing their advantages and limitations. Consequently, the challenges and future perspectives were considered.

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.

Organism type of infection is associated with prognosis in sepsis: an analysis from the MIMIC-IV database

BACKGROUND

Sepsis has a high mortality rate, which is expensive to treat, and is a major drain on healthcare resources; it seriously impacts the quality of human life. The clinical features of positive or non-positive blood cultures have been reported, but the clinical features of sepsis with different microbial infections and how they contribute to clinical outcomes have not been adequately described.

METHODS

We extracted clinical data of septic patients with a single pathogen from the online Medical Information Mart for Intensive Care(MIMIC)-IV database. Based on microbial cultures, patients were classified into Gram-negative, Gram-positive, and fungal groups. Then, we analyzed the clinical characteristics of sepsis patients with Gram-negative, Gram-positive, and fungal infections. The primary outcome was 28-day mortality. The secondary outcomes were in-hospital mortality, the length of hospital stay, the length of ICU stay, and the ventilation duration. In addition, Kaplan-Meier analysis was used for the 28-day cumulative survival rate of patients with sepsis. Finally, we performed further univariate and multivariate regression analyses for 28-day mortality and created a nomogram for predicting 28-day mortality.

RESULTS

The analysis showed that bloodstream infections showed a statistically significant difference in survival between Gram-positive and fungal organisms; drug resistance only reached statistical significance for Gram-positive bacteria. Through univariate and multivariate analysis, it was found that both the Gram-negative bacteria and fungi were independent risk factors for the short-term prognosis of sepsis patients. The multivariate regression model showed good discrimination, with a C-index of 0.788. We developed and validated a nomogram for the individualized prediction of 28-day mortality in patients with sepsis. Application of the nomogram still gave good calibration.

CONCLUSIONS

Organism type of infection is associated with mortality of sepsis, and early identification of the microbiological type of a patient with sepsis will provide an understanding of the patient's condition and guide treatment.

Short course antibiotic treatment of Gram-negative bacteraemia (GNB5): a study protocol for a randomised controlled trial

INTRODUCTION

Prolonged use of antibiotics is closely related to antibiotic-associated infections, antimicrobial resistance and adverse drug events. The optimal duration of antibiotic treatment for Gram-negative bacteremia (GNB) with a urinary tract source of infection is poorly defined.

METHODS AND ANALYSIS

Investigator-initiated multicentre, non-blinded, non-inferiority randomised controlled trial with two parallel treatment arms. One arm will receive shortened antibiotic treatment of 5 days and the other arm will receive antibiotic treatment of 7 days or longer. Randomisation will occur in equal proportion (1:1) no later than day 5 of effective antibiotic treatment as determined by antibiogram. Immunosuppressed patients and those with GNB due to non-fermenting bacilli (Acinetobacter spp, Pseudomonas spp), Brucella spp, Fusobacterium spp or polymicrobial growth are ineligible.The primary endpoint is 90-day survival without clinical or microbiological failure to treatment. Secondary endpoints include all-cause mortality, total duration of antibiotic treatment, hospital readmission and Clostridioides difficile infection. Interim safety analysis will be performed after the recruitment of every 100 patients. Given an event rate of 12%, a non-inferiority margin of 10%, and 90% power, the required sample size to determine non-inferiority is 380 patients. Analyses will be performed on both intention-to-treat and per-protocol populations.

ETHICS AND DISSEMINATION

The study is approved by the Danish Regional Committee on Health Research (H-19085920) and the Danish Medicines Agency (2019-003282-17). The results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.Gov:NCT04291768.

The economic burden of antibiotic resistance: A systematic review and meta-analysis

INTRODUCTION

Antibiotic resistance (ABR) has substantial global public health concerns. This systematic review aimed to synthesise recent evidence estimating the economic burden of ABR, characterised by study perspectives, healthcare settings, study design, and income of the countries.

METHODS

This systematic review included peer-reviewed articles from PubMed, Medline, and Scopus databases, and grey literature on the topic of the economic burden of ABR, published between January 2016 and December 2021. The study was reported in line with 'Preferred Reporting Items for Systematic Review and Meta-Analysis' (PRISMA). Two reviewers independently screened papers for inclusion first by title, then abstract, and then the full text. Study quality was assessed using appropriate quality assessment tools. Narrative synthesis and meta-analyses of the included studies were conducted.

RESULTS

A total of 29 studies were included in this review. Out of these studies, 69% (20/29) were conducted in high-income economies and the remainder were conducted in upper-and-middle income economies. Most of the studies were conducted from a healthcare or hospital perspective (89.6%, 26/29) and 44.8% (13/29) studies were conducted in tertiary care settings. The available evidence indicates that the attributable cost of resistant infection ranges from -US$2,371.4 to +US$29,289.1 (adjusted for 2020 price) per patient episode; the mean excess length of stay (LoS) is 7.4 days (95% CI: 3.4-11.4), the odds ratios of mortality for resistant infection is 1.844 (95% CI: 1.187-2.865) and readmission is 1.492 (95% CI: 1.231-1.807).

CONCLUSION

Recent publications show that the burden of ABR is substantial. There is still a lack of studies on the economic burden of ABR from low-income economies, and lower-middle-income economies, from a societal perspective, and in relation to primary care. The findings of this review may be of value to researchers, policymakers, clinicians, and those who are working in the field of ABR and health promotion.

SYSTEMATIC REVIEW REGISTRATION

CRD42020193886.

Attributable Patient Cost of Antimicrobial Resistance: A Prospective Parallel Cohort Study in Two Public Teaching Hospitals in Ghana

OBJECTIVE

The aim of this study was to evaluate the attributable patient cost of antimicrobial resistance (AMR) in Ghana to provide empirical evidence to make a case for improved AMR preventive strategies in hospitals and the general population.

METHODS

A prospective parallel cohort design in which participants were enrolled at the time of hospital admission and remained until 30 days after the diagnosis of bacteraemia or discharge from the hospital/death. Patients were matched on age group (± 5 years the age of AMR patients), treatment ward, sex, and bacteraemia type. The AMR cohort included all inpatients with a positive blood culture of Escherichia coli or Klebsiella spp., resistant to third-generation cephalosporins (3GC), or methicillin-resistant Staphylococcus aureus (MRSA). We matched the AMR cohort (n = 404) with two control arms, i.e., patients with the same bacterial infections susceptible to 3GC or S. aureus that was methicillin-susceptible (susceptible cohort; n = 152), and uninfected patients (uninfected cohort; n = 404). Settings were Korle-Bu and Komfo Anokye Teaching Hospitals, Ghana. The outcome measures were the length of hospital stay (LOS) and the associated patient costs. Outcomes were evaluated from the patient perspective.

RESULTS

From a total of 5752 blood cultures screened, 1836 participants had growth in blood culture, of which, based on our inclusion criteria, 426 were enrolled into the AMR cohort; however, only 404 completed the follow-up and were matched with participants in the two control cohorts. Patients in the AMR cohort stayed approximately 5 more days (95% confidence interval [CI] 4.0-6.0) and 8 more days (95% CI 7.2-8.6) compared with the susceptible and uninfected cohorts, respectively. The mean extra patient cost due to AMR relative to the susceptible cohort was US$1300 (95% CI 1018-1370), of which about 30% resulted from productivity loss due to presenteeism and absenteeism from work. Overall, the estimated annual patient cost due to AMR translates to about US$1 million and US$1.4 million when compared with the susceptible and uninfected cohorts, respectively.

CONCLUSION

We have shown that AMR is associated with a significant excess LOS and patient costs in Ghana using prospective data from two public tertiary hospitals. This calls for infection prevention and control strategies aimed at mitigating the prevalence of AMR.

Optical Methods for Label-Free Detection of Bacteria

Pathogenic bacteria are the leading causes of food-borne and water-borne infections, and one of the most serious public threats. Traditional bacterial detection techniques, including plate culture, polymerase chain reaction, and enzyme-linked immunosorbent assay are time-consuming, while hindering precise therapy initiation. Thus, rapid detection of bacteria is of vital clinical importance in reducing the misuse of antibiotics. Among the most recently developed methods, the label-free optical approach is one of the most promising methods that is able to address this challenge due to its rapidity, simplicity, and relatively low-cost. This paper reviews optical methods such as surface-enhanced Raman scattering spectroscopy, surface plasmon resonance, and dark-field microscopic imaging techniques for the rapid detection of pathogenic bacteria in a label-free manner. The advantages and disadvantages of these label-free technologies for bacterial detection are summarized in order to promote their application for rapid bacterial detection in source-limited environments and for drug resistance assessments.

The Prevalence of Multidrug-Resistant Escherichia coli Producing ESBL among Male and Female Patients with Urinary Tract Infections in Riyadh Region, Saudi Arabia

The Escherichia coli that produces extended-spectrum lactamases (ESBL-E. coli) can develop resistance to many antibiotics. The control of ESBL-E. coli disorders is challenging due to their restricted therapeutic approaches, so this study aims to determine the prevalence and pattern of the antibiotic resistance of ESBL-E. coli among male and female patients with urinary tract infections in Riyadh, Saudi Arabia. During the period of 2019 to 2020 at King Fahd Medical City, Riyadh, 2250 urine samples from patients with urinary tract infections (UTIs) were collected, and microbial species were cultured and identified using standard biochemical techniques. A double-disc synergy test was used to identify ESBL-producing strains of E. coli, and an in vitro method and the clinical laboratory standard institute (CLSI) criteria were employed to determine the resistance of these strains to antimicrobial drugs. ESBL-E. coli was detected in 510 (33.49%) of the 1523 E. coli isolates, 67.27% of which were recovered from women and 33.7% of which were recovered from men. A total of 284 (55.69%) ESBL-E. coli isolates were found in patients under 50 years of age, and 226 (44.31%) were found in patients over 50 years of age. Nearly all the isolates of ESBL-E. coli were resistant to cephalosporins (ceftriaxone, cefotaxime, cefepime, cefuroxime, and cephalothin) and penicillin (ampicillin), whereas the majority of the isolates were sensitive to several carbapenems (imipenem, meropenem, and ertapenem), aminoglycosides (amikacin), and nitrofurantoins. The development of antibiotic resistance by ESBL-E. coli, the most frequent pathogen linked to urinary tract infections, plays a crucial role in determining which antibiotic therapy is appropriate.

Transmission of gram-negative antibiotic-resistant bacteria following differing exposure to antibiotic-resistance reservoirs in a rural community: a modelling study for bloodstream infections

Exposure to community reservoirs of gram-negative antibiotic-resistant bacteria (GN-ARB) genes poses substantial health risks to individuals, complicating potential infections. Transmission networks and population dynamics remain unclear, particularly in resource-poor communities. We use a dynamic compartment model to assess GN-ARB transmission quantitatively, including the susceptible, colonised, infected, and removed populations at the community-hospital interface. We used two side streams to distinguish between individuals at high- and low-risk exposure to community ARB reservoirs. The model was calibrated using data from a cross-sectional cohort study (N = 357) in Chile and supplemented by existing literature. Most individuals acquired ARB from the community reservoirs (98%) rather than the hospital. High exposure to GN-ARB reservoirs was associated with 17% and 16% greater prevalence for GN-ARB carriage in the hospital and community settings, respectively. The higher exposure has led to 16% more infections and attributed mortality. Our results highlight the need for early-stage identification and testing capability of bloodstream infections caused by GN-ARB through a faster response at the community level, where most GN-ARB are likely to be acquired. Increasing treatment rates for individuals colonised or infected by GN-ARB and controlling the exposure to antibiotic consumption and GN-ARB reservoirs, is crucial to curve GN-ABR transmission.

LC-MS/MS-Based Fungicide Accumulation Assay to Demonstrate Efflux Activity in the Wheat Pathogen Zymoseptoria tritici

Increased drug efflux compromises the efficacy of a large panel of treatments in the clinic against cancer or bacterial, fungal, and viral diseases, and in agriculture due to the emergence of multidrug-resistant pathogenic fungi. Until recently, to demonstrate increased drug efflux, the use of labeled drugs or fluorescent dyes was necessary. With the increasing sensitivity of detection devices, direct assessment of drug efflux has become realistic. Here, we describe a medium-throughput method to assess the intracellular drug concentration in the plant pathogenic fungus Zymoseptoria tritici cultivated in the presence of a sublethal fungicide concentration. As a model fungicide, we used the succinate-dehydrogenase inhibitor boscalid. The boscalid concentration was assessed in the different culture fractions using mass spectrometry linked to liquid chromatography (LC-MS/MS). The ratio between the intracellular and total boscalid amount was used as an inversed proxy for the efflux activity. Using isogenic mutant strains known for their differential efflux capacities, we validated the negative correlation between the intracellular boscalid concentration and efflux activity. In addition, intra-cellular fungicide accumulation explains the susceptibility of the tested strains to boscalid. This assay may be useful in lead development when a new molecule displays good inhibitory activity against its isolated target protein but fails to control the target organism.

The Impact of Antimicrobial Stewardship and Infection Control Interventions on Acinetobacter baumannii Resistance Rates in the ICU of a Tertiary Care Center in Lebanon

Antimicrobial resistance is a serious threat to global health, causing increased mortality and morbidity especially among critically ill patients. This toll is expected to rise following the COVID-19 pandemic. Carbapenem-resistant Acinetobacter baumannii (CRAb) is among the Gram-negative pathogens leading antimicrobial resistance globally; it is listed as a critical priority pathogen by the WHO and is implicated in hospital-acquired infections and outbreaks, particularly in critically ill patients. Recent reports from Lebanon describe increasing rates of infection with CRAb, hence the need to develop concerted interventions to control its spread. We set to describe the impact of combining antimicrobial stewardship and infection control measures on resistance rates and colonization pressure of CRAb in the intensive care units of a tertiary care center in Lebanon before the COVID-19 pandemic. The antimicrobial stewardship program introduced a carbapenem-sparing initiative in April 2019. During the same period, infection control interventions involved focused screening, monitoring, and tracking of CRAb, as well as compliance with specific measures. From January 2018 to January 2020, we report a statistically significant decrease in carbapenem consumption and a decrease in resistance rates of isolated A. baumannii. The colonization pressure of CRAb also decreased significantly, reaching record low levels at the end of the intervention period. The results indicate that a multidisciplinary approach and combined interventions between the stewardship and infection control teams can lead to a sustained reduction in resistance rates and CRAb spread in ICUs.

Appropriateness of Antibiotic Prescribing in Hospitalized Children: A Focus on the Real-World Scenario of the Different Paediatric Subspecialties

Background: Antibiotics are prescribed for children both in hospital and community settings, particularly at preschool age. Italy shows a high rate of inappropriate antibiotic prescriptions which may represent a serious problem in the hospital scenario. Thus, the aim of this study was to investigate appropriateness of antibiotic prescribing in the context of different paediatric subspecialties in a hospital setting.

Methods: Antibiotics prescribing was retrospectively analysed in paediatric patients (0–18 years) admitted in the emergency paediatrics, general paediatrics, paediatric nephrology and rheumatology units between January and December 2019. Patients were stratified by age in neonates, infants, toddlers, children and adolescents. Assessments were conducted by trained local assessors and appropriateness was classified as appropriate, inappropriate and not assessable.

Results: Empirical antibiotics were mainly prescribed following a diagnosis of respiratory, gastrointestinal and/or urinary infection. A total of 825 antibiotic prescriptions were recorded in the three subspecialties; 462 antibiotic prescriptions (56%) out of 825 were assessed as inappropriate and 55 prescriptions (6.7%) were not assessable. Inappropriateness considerably varied within subspecialties: the risk of inappropriate antibiotic prescribing was higher in emergency paediatrics and general paediatric than in children, according to age. Ceftriaxone and clarithromycin were the most inappropriate prescribed antibiotics in the emergency paediatrics whereas amoxicillin/clavulanic acid represented the most inappropriate antibiotic prescribed in general paediatrics.

Conclusion: The present data may be useful in order to reduce inappropriate antibiotic prescribing in the paediatric setting; antibiotic stewardship and clinical improvement programs in hospital paediatric care are strongly recommended.

Multidrug-Resistant Bloodstream Infections in Internal Medicine: Results from a Single-Center Study

OBJECTIVES

Infections due to multidrug-resistant organisms (MDROs) are expanding globally and are associated with higher mortality rates and hospital-related costs. The objectives of this study were to analyze the trends of MDRO bacteremia and antimicrobial resistance rates in Internal Medicine wards of our hospital and to identify the variables associated with these infections.

METHODS

During a 6-year period (July 1, 2011-June 30, 2017), patients with positive blood culture isolates hospitalized in the Internal Medicine wards in the Santa Croce and Carle Hospital in Cuneo, Italy, were assessed. We performed an analysis taking into consideration the time trends and frequencies of MDRO infections, as well as a case-control study to identify clinical-demographic variables associated with MDRO bacteremias.

RESULTS

During the study period a total of 596 blood cultures were performed in 577 patients. The most frequently identified organism was Escherichia coli (33.7%), followed by Staphylococcus aureus (15.6%) and S epidermidis (7.4%). The percentage of resistance to methicillin among S aureus isolates showed a decreasing trend, whereas rates of extended-spectrum β-lactamase-producing Enterobacteriaceae and carbapenemase-producing Klebsiella pneumoniae increased during the study period. Multivariate analysis showed that the nosocomial origin of the infection, hospitalization during the previous 3 months, residence in long-term care facilities, presence of a device, antibiotic exposure during the previous 3 months, and cerebrovascular disease were independently associated with bacteremia by resistant microorganisms.

CONCLUSIONS

Our analysis reveals a concerning microbiological situation in an Internal Medicine setting, in line with other national and regional data. The risk variables for infection by MDRO identified in our study correspond to those reported in the literature, although studies focused on Internal Medicine settings appear to be limited.

Antimicrobial Resistance and Implications: Impact on Pregnant Women with Urinary Tract Infections

Urinary Tract Infections (UTI) is one of the most common infections, especially among women. Presently accessible antibiotics are a clinician’s first line of defense to treat infections, but antimicrobial resistance menace to reduce their efficacy. The consequences of multi-drug resistance to antibiotics are enhanced morbidity and mortality rates. The yearly death toll is >700,000 population worldwide, rising to ~10 million by 2050. There is a lack of novel antibiotics for UTIs as the return on its investment is poor compared to medicines for lifestyle diseases. The three organisms of utmost worry are methicillin-resistant Staphylococcus aureus (MRSA), Carbapenems and third-generation Cephalosporins resistant Klebsiella pneumoniae, Fluoroquinolones and third-generation Cephalosporins resistant Escherichia coli (E. coli). Among these, Escherichia coli is the foremost cause of community-acquired UTI infections throughout the globe, mainly due to the absence of alertness and inappropriate wastewater treatment. The purpose of this review article is to explore literature on uropathogens, the pattern of their antimicrobial resistance, and the hospital practices concerning the spread, as inadequate studies have been carried out and published on this topic. Hospital personnel are usually familiar with the management of infections, but most do not understand the conditions in their hospital. Implications of hospital practices play a major role in controlling hospital-acquired UTIs and the burden of its antimicrobial resistance. A complete approach involving financial and human resources will improve the infection control practices in hospitals without a doubt. Strict infection control measures in hospitals can help to reduce the number of hospital-acquired infections in pregnant women.

Anti-infective Medicines Use in Children and Neonates With Pre-existing Kidney Dysfunction: A Systematic Review

Background

Dosing recommendations for anti-infective medicines in children with pre-existing kidney dysfunction are derived from adult pharmacokinetics studies and adjusted to kidney function. Due to neonatal/pediatric age and kidney impairment, modifications in renal clearance and drug metabolism make standard anti-infective dosing for children and neonates inappropriate, with a risk of drug toxicity or significant underdosing. The aim of this study was the systematic description of the use of anti-infective medicines in pediatric patients with pre-existing kidney impairment.

Methods

A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The EMBASE, Medline and Cochrane databases were searched on September 21st, 2021. Studies in all languages reporting data on pre-defined outcomes (pharmacokinetics-PK, kidney function, safety and efficacy) regarding the administration of anti-infective drugs in children up to 18 years with pre-existing kidney dysfunction were included.

Results

29 of 1,792 articles were eligible for inclusion. There were 13 case reports, six retrospective studies, nine prospective studies and one randomized controlled trial (RCT), reporting data on 2,168 pediatric patients. The most represented anti-infective class was glycopeptides, with seven studies on vancomycin, followed by carbapenems, with five studies, mostly on meropenem. Antivirals, aminoglycosides and antifungals counted three articles, followed by combined antibiotic therapy, cephalosporins, lipopeptides with two studies, respectively. Penicillins and polymixins counted one study each. Nine studies reported data on patients with a decreased kidney function, while 20 studies included data on kidney replacement therapy (KRT). Twenty-one studies reported data on PK. In 23 studies, clinical outcomes were reported. Clinical cure was achieved in 229/242 patients. There were four cases of underdosing, one case of overdosing and 13 reported deaths.

Conclusion

This is the first systematic review providing evidence of the use of anti-infective medicines in pediatric patients with impaired kidney function or requiring KRT. Dosing size or interval adjustments in pediatric patients with kidney impairment vary according to age, critical illness status, decreased kidney function and dialysis type. Our findings underline the relevance of population PK in clinical practice and the need of developing predictive specific models for critical pediatric patients.

Risk factors for carriage of antimicrobial-resistant bacteria in community dwelling-children in the Asia-Pacific region: a systematic review and meta-analysis

Background

Antimicrobial resistance is an increasingly important issue in public health as antibiotics are overused. Resistance to antimicrobial agents can pose significant challenges to infection treatment.

Objectives

To evaluate risk factors associated with carriage of antimicrobial-resistant (AMR) bacteria in children in the Asia-Pacific region to consolidate evidence for future implementation of antibiotic prescribing practice.

Methods

Three electronic databases-PubMed, EMBASE and Cochrane Library-were searched. Observational studies that investigated the risk factors for carriage of MRSA, penicillin-resistant Streptococcus pneumoniae, ESBL-producing Escherichia coli and Klebsiella pneumoniae among the paediatric population in community settings in the Asia-Pacific region were considered eligible. Summary statistics from the identified studies were pooled using meta-analyses.

Results

From the 4145 search results, 25 papers were included in this review. Sixteen papers were included in the meta-analysis based on reported risk factors. Young age of 2-6 months compared with children aged 7-60 months (OR 2.74, 95% CI: 1.75-4.29), antibiotic use within the past 3 months (OR 2.65, 95% CI: 1.70-4.12), daycare attendance (OR 1.49, 95% CI: 1.17-1.91) and hospital admission within the past 3 months (OR 3.43, 95% CI: 2.13-5.51) were found to be significant risk factors for AMR bacterial carriage, whilst breastfeeding (OR 0.69, 95% CI: 0.60-0.81) and concurrent colonization of S. pneumoniae (OR 0.59, 95% CI: 0.38-0.91) are protective factors.

Conclusions

The findings support that there are a number of significant risk factors associated with carriage of AMR bacteria in the Asia-Pacific paediatric population. To combat antimicrobial resistance in the future, these risk factors should be considered, and measures taken to mitigate associated carriage.

A Data-Driven Framework for Identifying Intensive Care Unit Admissions Colonized With Multidrug-Resistant Organisms

Background

The rising prevalence of multi-drug resistant organisms (MDROs), such as Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant Enterococci (VRE), and Carbapenem-resistant Enterobacteriaceae (CRE), is an increasing concern in healthcare settings.

Materials and Methods

Leveraging data from electronic healthcare records and a unique MDRO universal screening program, we developed a data-driven modeling framework to predict MRSA, VRE, and CRE colonization upon intensive care unit (ICU) admission, and identified the associated socio-demographic and clinical factors using logistic regression (LR), random forest (RF), and XGBoost algorithms. We performed threshold optimization for converting predicted probabilities into binary predictions and identified the cut-off maximizing the sum of sensitivity and specificity.

Results

Four thousand six hundred seventy ICU admissions (3,958 patients) were examined. MDRO colonization rate was 17.59% (13.03% VRE, 1.45% CRE, and 7.47% MRSA). Our study achieved the following sensitivity and specificity values with the best performing models, respectively: 80% and 66% for VRE with LR, 73% and 77% for CRE with XGBoost, 76% and 59% for MRSA with RF, and 82% and 83% for MDRO (i.e., VRE or CRE or MRSA) with RF. Further, we identified several predictors of MDRO colonization, including long-term care facility stay, current diagnosis of skin/subcutaneous tissue or infectious/parasitic disease, and recent isolation precaution procedures before ICU admission.

Conclusion

Our data-driven modeling framework can be used as a clinical decision support tool for timely predictions, characterization and identification of high-risk patients, and selective and timely use of infection control measures in ICUs.

Surgical Antimicrobial Prophylaxis in Abdominal Surgery for Neonates and Paediatrics: A RAND/UCLA Appropriateness Method Consensus Study

Surgical site infections (SSIs), i.e., surgery-related infections that occur within 30 days after surgery without an implant and within one year if an implant is placed, complicate surgical procedures in up to 10% of cases, but an underestimation of the data is possible since about 50% of SSIs occur after the hospital discharge. Gastrointestinal surgical procedures are among the surgical procedures with the highest risk of SSIs, especially when colon surgery is considered. Data that were collected from children seem to indicate that the risk of SSIs can be higher than in adults. This consensus document describes the use of preoperative antibiotic prophylaxis in neonates and children that are undergoing abdominal surgery and has the purpose of providing guidance to healthcare professionals who take care of children to avoid unnecessary and dangerous use of antibiotics in these patients. The following surgical procedures were analyzed: (1) gastrointestinal endoscopy; (2) abdominal surgery with a laparoscopic or laparotomy approach; (3) small bowel surgery; (4) appendectomy; (5) abdominal wall defect correction interventions; (6) ileo-colic perforation; (7) colorectal procedures; (8) biliary tract procedures; and (9) surgery on the liver or pancreas. Thanks to the multidisciplinary contribution of experts belonging to the most important Italian scientific societies that take care of neonates and children, this document presents an invaluable reference tool for perioperative antibiotic prophylaxis in the paediatric and neonatal populations.

Membrane-Active Antibacterial Agents Based on Calix[4]arene Derivatives: Synthesis and Biological Evaluation

Bacteria have developed increasing resistance to currently used antimicrobial agents. New classes of antimicrobial drugs are urgently required to fight drug-resistant pathogens. Here, we designed and synthesized a series of calix[4]arene derivatives as antibacterial agents by biomimicking the structural properties and biological functions of antibacterial peptides. After introducing cationic hydrophilic moieties and preliminary structural optimization, we obtained a lead compound (16) that exhibited excellent antibacterial activity against Gram-positive bacteria, low toxicity toward mammalian cells and poor hemolytic activity. The antibacterial mechanism studies showed that compound 16 can destroy bacterial cell membrane directly, leading to bacterial death and a low tendency to develop bacterial resistance.

Disparity in socio-economic status explains the pattern of self-medication of antibiotics in India: understanding from game-theoretic perspective

The emergence of antimicrobial resistance has raised great concern for public health in many lower-income countries including India. Socio-economic determinants like poverty, health expenditure and awareness accelerate this emergence by influencing individuals' attitudes and healthcare practices such as self-medication. This self-medication practice is highly prevalent in many countries, where antibiotics are available without prescriptions. Thus, complex dynamics of drug- resistance driven by economy, human behaviour, and disease epidemiology poses a serious threat to the community, which has been less emphasized in prior studies. Here, we formulate a game-theoretic model of human choices in self-medication integrating economic growth and disease transmission processes. We show that this adaptive behaviour emerges spontaneously in the population through a self-reinforcing process and continual feedback from the economy, resulting in the emergence of resistance as externalities of human choice under resource constraints situations. We identify that the disparity between social-optimum and individual interest in self-medication is primarily driven by the effectiveness of treatment, health awareness and public health interventions. Frequent multiple-peaks of resistant strains are also observed when individuals imitate others more readily and self-medication is more likely. Our model exemplifies that timely public health intervention for financial risk protection, and antibiotic stewardship policies can improve the epidemiological situation and prevent economic collapse.

Challenges to Antimicrobial Stewardship in the Countries of the Arab League: Concerns of Worsening Resistance during the COVID-19 Pandemic and Proposed Solutions

The COVID-19 pandemic is expected to worsen the global problem of antimicrobial resistance (AMR). There is a heightened interest in understanding this effect and to develop antimicrobial stewardship (AMS) interventions accordingly to curb this threat. Our paper aims to evaluate the potential magnitude of COVID-19 on AMR and AMS with a focus on the countries of the Arab league, given the social, political, and economic environments. We also evaluate obstacles in applying the rational use of antibiotics, monitoring resistance trends in the midst of the pandemic, and evaluating the impact of the economic crisis in some countries. We aim to raise awareness about the potential effects of antibiotic overuse during the pandemic and to propose practical approaches to tackle this issue.

Production and Purification of Two Bioactive Antimicrobial Peptides Using a Two-Step Approach Involving an Elastin-Like Fusion Tag

Antimicrobial resistance is an increasing global threat, demanding new therapeutic biomolecules against multidrug-resistant bacteria. Antimicrobial peptides (AMPs) are promising candidates for a new generation of antibiotics, but their potential application is still in its infancy, mostly due to limitations associated with large-scale production. The use of recombinant DNA technology for the production of AMPs fused with polymer tags presents the advantage of high-yield production and cost-efficient purification processes at high recovery rates. Owing to their unique properties, we explored the use of an elastin-like recombinamer (ELR) as a fusion partner for the production and isolation of two different AMPs (ABP-CM4 and Synoeca-MP), with an interspacing formic acid cleavage site. Recombinant AMP-ELR proteins were overproduced in Escherichia coli and efficiently purified by temperature cycles. The introduction of a formic acid cleavage site allowed the isolation of AMPs, resorting to a two-step methodology involving temperature cycles and a simple size-exclusion purification step. This simple and easy-to-implement purification method was demonstrated to result in high recovery rates of bioactive AMPs. The minimum inhibitory concentration (MIC) of the free AMPs was determined against seven different bacteria of clinical relevance (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and two Burkholderia cenocepacia strains), in accordance with the EUCAST/CLSI antimicrobial susceptibility testing standards. All the bacterial strains (except for Pseudomonas aeruginosa) were demonstrated to be susceptible to ABP-CM4, including a resistant Burkholderia cenocepacia clinical strain. As for Synoeca-MP, although it did not inhibit the growth of Pseudomonas aeruginosa or Klebsiella pneumoniae, it was demonstrated to be highly active against the remaining bacteria. The present work provides the basis for the development of an efficient and up-scalable biotechnological platform for the production and purification of active AMPs against clinically relevant bacteria.

Directed evolution predicts cytochrome b G37V target site modification as probable adaptive mechanism towards the QiI fungicide fenpicoxamid in Zymoseptoria tritici

Acquired resistance is a threat to antifungal efficacy in medicine and agriculture. The diversity of possible resistance mechanisms and highly adaptive traits of pathogens make it difficult to predict evolutionary outcomes of treatments. We used directed evolution as an approach to assess the resistance risk to the new fungicide fenpicoxamid in the wheat pathogenic fungus Zymoseptoria tritici. Fenpicoxamid inhibits complex III of the respiratory chain at the ubiquinone reduction site (Qi site) of the mitochondrially encoded cytochrome b, a different site than the widely used strobilurins which inhibit the same complex at the ubiquinol oxidation site (Q_o site). We identified the G37V change within the cytochrome b Q_i site as the most likely resistance mechanism to be selected in Z. tritici. This change triggered high fenpicoxamid resistance and halved the enzymatic activity of cytochrome b, despite no significant penalty for in vitro growth. We identified negative cross-resistance between isolates harbouring G37V or G143A, a Q_o site change previously selected by strobilurins. Double mutants were less resistant to both QiIs and quinone outside inhibitors compared to single mutants. This work is a proof of concept that experimental evolution can be used to predict adaptation to fungicides and provides new perspectives for the management of QiIs.

Strategies for Effective Infection Prevention Programs: Structures, Processes, and Funding

Successful Infection Prevention Programs (IPPs) consist of a multidisciplinary team led by a hospital epidemiologist and managed by infection preventionists. Knowledge of the economics of health care-associated infections (HAIs) and the ability to make a business plan is now essential to the success of programs. Prevention of HAIs is the core function of IPPs with impact on patient outcomes, quality of care, and cost savings for hospitals. This article discusses the structure and responsibilities of an IPP, the regulatory pressures and opportunities that these programs face, and how to build and manage a successful program.

Development of Antimicrobial Laser-Induced Photodynamic Therapy Based on Ethylcellulose/Chitosan Nanocomposite with 5,10,15,20-Tetrakis(m-Hydroxyphenyl)porphyrin

The development of new antimicrobial strategies that act more efficiently than traditional antibiotics is becoming a necessity to combat multidrug-resistant pathogens. Here we report the efficacy of laser-light-irradiated 5,10,15,20-tetrakis(m-hydroxyphenyl)porphyrin (mTHPP) loaded onto an ethylcellulose (EC)/chitosan (Chs) nanocomposite in eradicating multi-drug resistant Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. Surface loading of the ethylcelllose/chitosan composite with mTHPP was carried out and the resulting nanocomposite was fully characterized. The results indicate that the prepared nanocomposite incorporates mTHPP inside, and that the composite acquired an overall positive charge. The incorporation of mTHPP into the nanocomposite enhanced the photo- and thermal stability. Different laser wavelengths (458; 476; 488; 515; 635 nm), powers (5-70 mW), and exposure times (15-45 min) were investigated in the antimicrobial photodynamic therapy (aPDT) experiments, with the best inhibition observed using 635 nm with the mTHPP EC/Chs nanocomposite for C. albicans (59 ± 0.21%), P. aeruginosa (71.7 ± 1.72%), and S. aureus (74.2 ± 1.26%) with illumination of only 15 min. Utilization of higher doses (70 mW) for longer periods achieved more eradication of microbial growth.

Microbial Contamination in Hospital Environment Has the Potential to Colonize Preterm Newborns' Nasal Cavities

Infants born before 28 weeks are at risk of contracting healthcare-associated infections (HAIs), which could be caused by pathogens residing on contaminated hospital surfaces. In this longitudinal study, we characterized by NGS the bacterial composition of nasal swabs of preterm newborns, at the time of birth and after admission to the Neonatal Intensive Care Unit (NICU), comparing it with that of the environmental wards at the time of delivery and during the hospitalization. We characterized the resistome on the samples too. The results showed that environmental microorganisms responsible for HAIs, in particular Staphylococcus spp., Streptococcus spp., Escherichia-Shigella spp., and K. pneumoniae, were detected in higher percentages in the noses of the babies after 13 days of hospitalization, in terms of the number of colonized patients, microorganism amount, and relative abundance. The analysis of nasal bacteria resistome evidenced the absence of resistance genes at the time of birth, some of which appeared and increased after the admission in the NICU. These data suggest that hospital surface microbiota might be transported to respiratory mucosae or other profound tissues. Our study highlights the importance of a screening that allows characterizing the microbial profile of the environment to assess the risk of colonization of the newborn.

The healthcare costs of antimicrobial resistance in Lebanon: a multi-centre prospective cohort study from the payer perspective

Background

Our aim was to examine whether the length of stay, hospital charges and in-hospital mortality attributable to healthcare- and community-associated infections due to antimicrobial-resistant bacteria were higher compared with those due to susceptible bacteria in the Lebanese healthcare settings using different methodology of analysis from the payer perspective .

Methods

We performed a multi-centre prospective cohort study in ten hospitals across Lebanon. The sample size consisted of 1289 patients with documented healthcare-associated infection (HAI) or community-associated infection (CAI). We conducted three separate analysis to adjust for confounders and time-dependent bias: (1) Post-HAIs in which we included the excess LOS and hospital charges incurred after infection and (2) Matched cohort, in which we matched the patients based on propensity score estimates (3) The conventional method, in which we considered the entire hospital stay and allocated charges attributable to CAI. The linear regression models accounted for multiple confounders.

Results

HAIs and CAIs with resistant versus susceptible bacteria were associated with a significant excess length of hospital stay (2.69 days [95% CI,1.5–3.9]; p < 0.001) and (2.2 days [95% CI,1.2–3.3]; p < 0.001) and resulted in additional hospital charges ($1807 [95% CI, 1046–2569]; p < 0.001) and ($889 [95% CI, 378–1400]; p = 0.001) respectively. Compared with the post-HAIs analysis, the matched cohort method showed a reduction by 26 and 13% in hospital charges and LOS estimates respectively. Infections with resistant bacteria did not decrease the time to in-hospital mortality, for both healthcare- or community-associated infections. Resistant cases in the post-HAIs analysis showed a significantly higher risk of in-hospital mortality (odds ratio, 0.517 [95% CI, 0.327–0.820]; p = 0.05).

Conclusion

This is the first nationwide study that quantifies the healthcare costs of antimicrobial resistance in Lebanon. For cases with HAIs, matched cohort analysis showed more conservative estimates compared with post-HAIs method. The differences in estimates highlight the need for a unified methodology to estimate the burden of antimicrobial resistance in order to accurately advise health policy makers and prioritize resources expenditure.

Budget impact analysis of using procalcitonin to optimize antimicrobial treatment for patients with suspected sepsis in the intensive care unit and hospitalized lower respiratory tract infections in Argentina

BACKGROUND

Inappropriate antibiotic use represents a major global threat. Sepsis and bacterial lower respiratory tract infections (LRTIs) have been linked to antimicrobial resistance, carrying important consequences for patients and health systems. Procalcitonin-guided algorithms may represent helpful tools to reduce antibiotic overuse but the financial burden is unclear. The aim of this study was to estimate the healthcare and budget impact in Argentina of using procalcitonin-guided algorithms to guide antibiotic prescription.

METHODS

A decision tree was used to model health and cost outcomes for the Argentinean health system, over a one-year duration. Patients with suspected sepsis in the intensive care unit and hospitalized patients with LRTI were included. Model parameters were obtained from a focused, non-systematic, local and international bibliographic search, and validated by a panel of local experts. Deterministic and probabilistic sensitivity analyses were performed to analyze the uncertainty of parameters.

RESULTS

The model predicted that using procalcitonin-guided algorithms would result in 734.5 [95% confidence interval (CI): 1,105.2;438.8] thousand fewer antibiotic treatment days, 7.9 [95% CI: 18.5;8.5] thousand antibiotic-resistant cases avoided, and 5.1 [95% CI: 6.7;4.2] thousand fewer Clostridioides difficile cases. In total, this would save $422.4 US dollars (USD) [95% CI: $935;$267] per patient per year, meaning cost savings of $83.0 [95% CI: $183.6;$57.7] million USD for the entire health system and $0.4 [95% CI: $0.9;$0.3] million USD for a healthcare provider with 1,000 cases per year of sepsis and LRTI patients. The sensitivity analysis showed that the probability of cost-saving for the sepsis patient group was lower than for the LRTI patient group (85% vs. 100%).

CONCLUSIONS

Healthcare and financial benefits can be obtained by implementing procalcitonin-guided algorithms in Argentina. Although we found results to be robust on an aggregate level, some caution must be used when focusing only on sepsis patients in the intensive care unit.

Determinants of antibiotic over-prescribing for upper respiratory tract infections in an emergency department with good primary care access: a quantitative analysis

BACKGROUND

Upper respiratory tract infections (URTI) account for the highest proportion of non-urgent visits to the emergency department (ED), resulting in unnecessary antibiotic use.

AIM

This study sought to understand the determinants of antibiotic prescribing for URTI among 130 junior physicians in a busy adult ED in Singapore.

METHODS

Forty-four Likert-scale statements were developed with reference to a prior qualitative study, followed by an anonymous cross-sectional survey among ED junior physicians. Data analysis was performed with factor reduction and multivariable logistic regression.

FINDINGS

One-in-six (16.9%) physicians were high antibiotic prescribers (self-reported antibiotic prescribing rate of >30% of URTI patients). After adjusting for place of medical education and years of practice as a physician, perceived over-prescribing of antibiotics in the ED (adjusted odds ratio (OR) 2.37, 95% confidence interval (CI) (1.15, 4.86), P=0.019) and perceived compliance with the antibiotic prescribing practices in the ED (adjusted OR 2.10, 95% CI (1.02, 4.30), P=0.043) were positively associated with high antibiotic prescribing. In contrast, high antibiotic prescribers were 6.67 times (95% CI (1.67, 25.0), P=0.007) less likely to treat and manage patients with URTI symptomatically and 7.12 times (95% CI (1.28, 39.66), P=0.025) more likely to depend on diagnostic tests to prescribe antibiotics than the regular antibiotic prescribers.

CONCLUSION

Organizational-related factors (organizational norms and culture) were strong determinants of antibiotic prescribing practices for uncomplicated URTI in the ED. Other contributing factors include diagnostic uncertainty and knowledge gaps. Role-modelling of institutional best practice norms and clinical decision support tools based on local epidemiology can optimize antibiotic prescribing in the ED.

Predominance and clonal spread of CTX-M-15 in cefotaxime-resistant Klebsiella pneumoniae in Korea and their association with plasmid-mediated quinolone resistance determinants

INTRODUCTION

β-lactams and fluoroquinolones are extensively used worldwide in the treatment of infections caused by Enterobacterales. In this study, we investigated the prevalence of extended-spectrum β-lactamases (ESBL), their correlation with plasmid-mediated quinolone resistance determinants (PMQR) and clonal distribution among the cefotaxime-resistant K. pneumoniae isolates.

METHODS

In Korea, a total of 429 K. pneumoniae collected in 2015 were studied. Antimicrobial susceptibility test for cefotaxime, ciprofloxacin and levofloxacin was performed by broth microdilution method. By PCR and/or sequencing, mutations in gyrA and parC genes, PMQR genes and ESBL were identified. Multilocus-sequence-type (MLST) was determined for isolates harboring CTX-M-15.

RESULTS

Among the 149 K. pneumoniae showing cefotaxime MICs of >1 μg/ml, 142 (95.3%) isolates were ESBL-producers and CTX-M-15 was predominant (99 isolates). Among the 142 ESBL-producers, mutations in gyrA and parC were found in 112 (78.9%) and 93 isolates (65.5%), respectively. PMQR genes were detected in 141 isolates and the non-susceptibility rate to ciprofloxacin and levofloxacin was 95.1% (135/142) and 82.4% (117/142), respectively. The most frequently found PMQR combination was qnrB-aac(6')-Ib-cr-oqxAB, (58/142, 40.8%). By MLST, four major STs/CC: ST48, ST392, ST307 and CC15 accounted for 67% of the CTX-M-15 producers and the prevalence of qnrB was significantly higher in these four major STs/CC than other groups (P = 0.004). Of note, we found the additive effect of PMQR genes; the more PMQR genes, the higher ciprofloxacin MICs.

CONCLUSIONS

CTX-M-15 was predominant among the cefotaxime-resistant K. pneumoniae and co-harboring CTX-M-15 and PMQR genes, especially qnrB, seems to contribute the spread of high risk clones.