Surveillance of antimicrobial use and antimicrobial resistance in United States hospitals: project ICARE phase 2. Project Intensive Care Antimicrobial Resistance Epidemiology (ICARE) hospitals

Antimicrobial prescribing in referral hospitals in Timor-Leste: results of the first two national point prevalence surveys, 2020-21

Objectives

To describe antimicrobial use (AMU) in patients admitted to hospitals in Timor-Leste.

Methods

In 2020 and 2021, we undertook antimicrobial prescribing point prevalence surveys across all six hospitals in Timor-Leste (one national and five municipal) to describe AMU and appropriateness in admitted patients.

Results

In 2020, 291/394 (73.9%) surveyed patients had been prescribed antimicrobials, compared with 260/403 (64.5%) in 2021 (P = 0.004). Most (309/551; 56.1%) were prescribed one antimicrobial, and 179/551 (32.5%) were prescribed two. The most commonly prescribed antibiotics were ceftriaxone (38.5% in 2020, 41.5% in 2021) and ampicillin (35.7% in 2020, 32.3% in 2021), followed by gentamicin, metronidazole and cloxacillin. Reserve antibiotics like meropenem and vancomycin were minimally used. Of all antimicrobial prescriptions, 70.8% were deemed appropriate in 2020 and 69.1% in 2021. Antimicrobial prescriptions for surgical and post-partum prophylaxis were frequently deemed inappropriate [37/50 (74.0%) and 39/44 (88.6%) prescriptions, respectively].

Conclusions

Most patients admitted to hospital in Timor-Leste are prescribed antimicrobials, and approximately one-third of these prescriptions are inappropriate. However, this was in the context of limited local guideline availability at the time of surveys and limited microbiological culture capacity outside of the capital, Dili. Improved microbiological guidance, iterative guideline revisions based on local antimicrobial resistance (AMR) surveillance data, and enhanced stewardship activities including further point prevalence studies, could improve antimicrobial use, optimize patient outcomes and reduce AMR in Timor-Leste.

Unexpected Sudden Deaths Following the Co-administration of Ceftriaxone and Lansoprazole: A Case Series

Ceftriaxone and lansoprazole are commonly used in clinical settings, but recent analyses indicate a potential risk for QTc prolongation and cardiac events when used together. This case series examines three patients from a cohort of sudden death cases at a single institution over a decade, who received both medications within 24 hours before death. Three cases were identified, each with contributing factors for cardiac arrhythmias. The results underscore the importance of monitoring and possibly avoiding this drug combination in patients at risk of QT prolongation, pending further investigation into the underlying mechanisms.

Antibiotic treatment duration for culture-negative sepsis in the pediatric intensive care unit

Objective

Sepsis remains a leading cause of morbidity and mortality in children. There is very limited guidance for sepsis treatment when cultures remain negative. This study sought to determine the effectiveness of short versus long course of antibiotics when treating culture-negative sepsis and assess for subsequent multidrug-resistant organism (MDRO) acquisition.

Design

Retrospective cohort study.

Setting

Quaternary academic children's hospital.

Patients

Pediatric intensive care unit (ICU) patients with culture-negative sepsis receiving a minimum of 72 hours of antibiotics.

Methods

Patients found to have culture-negative sepsis from January 2017 to May 2020 were divided into two groups: short and long course of antibiotics. Various demographic and laboratory results were collected for each subject as available. Primary outcomes included mortality and lengths of stay. The secondary outcome was subsequent acquisition of a new MDRO.

Results

Eighty-six patients were treated for culture-negative sepsis with 43 patients in both the short- (< or = 7 days) and long-course (>7 days) treatment cohorts. Patients who received a short course of antibiotics had a lower overall mortality than those who received a long course (9.3% vs 25.6% p = 0.047), but there was no difference in 30-day mortality (p > 0.99). Patients in the short-course group had a shorter hospital length of stay (22 vs 30 days p = 0.018). New MDROs were found in 10% of all patients.

Conclusions

Treatment of culture-negative sepsis with short-course antibiotics was not associated with worse outcomes in ICU patients. These findings warrant further investigation with a larger, prospective, multi-center study.

Evaluation of antibiotic-resistant bacteria in home kitchens and bathrooms: Is there a link between home disinfectant use and antibiotic resistance?

OBJECTIVE

To determine the relationship between home disinfectant use and the prevalence of antibiotic resistance among environmental isolates of human pathogens.

METHODS

Bacteria were cultured from 5 kitchen and 5 bathroom sites using quantitative methods. Antibiotic susceptibility was determined by standard methods. Home disinfectant use was assessed via a questionnaire.

RESULTS

The overall total mean log10 counts (total CFU) for the kitchen and bathroom were 4.31 and 4.88, respectively. Gram-positive bacteria were more common in the bathroom (4.05) than in the kitchen (3.60), while Gram-negative bacilli were more common in the kitchen (4.23) than in the bathroom (3.86). The sink and bath drains were the most contaminated sites with 6.16-log10 of total CFU and 6.6-log10 in the kitchen and bathroom, respectively. Households reported cleaning frequency with a variety of commercial products. Most respondents used antibacterial products (eg, soaps, surface disinfectants) in the home. Antibiotic-resistant pathogens were infrequently isolated in the homes evaluated.

CONCLUSIONS

Compared to pathogens causing community-acquired clinical infections in the ICARE study, pathogens isolated from households are less likely to demonstrate antibiotic resistance. In addition, no relationship between antibacterial use or frequency of cleaning or disinfection and antibiotic resistance was revealed.

Multidrug-Resistant Enterococcal Infection in Surgical Patients, What Surgeons Need to Know

Enterococci are organisms that can be found in the normal intestinal and skin microbiota and show remarkable ability to acquire antibiotic resistance. This is an enormous challenge for surgeons when faced with surgical site infections caused by multidrug-resistant (MDR) Enterococci. Due to an increase in the prevalence of MDR Enterococcus within the last few decades, there has been a major decrease in therapeutic options, because the majority of E. faecium isolates are now resistant to ampicillin and vancomycin and exhibit high-level resistance to aminoglycosides, traditionally three of the most useful anti-enterococcal antibiotics. There is limited data regarding the magnitude and pattern of multidrug resistance among the enterococcal genus causing surgical site infections in hospitalized patients. The scope of the review is to summarize the most recent findings in the emergence of postoperative MDR Enterococci and discuss recent mechanisms of resistance and the best treatment options available.

Implementation of A Year-Long Antimicrobial Stewardship Program in A 227-Bed Community Hospital in Southern Italy

BACKGROUND

Healthcare-Acquired Infections (HAIs) are serious healthcare complications affecting hospital stay, in-hospital mortality, and costs. Root cause analysis has identified the inappropriate use of antibiotics as the main causative factor in the expansion of multi-drug-resistant organisms (MDRO) in our hospital. An Antimicrobial Stewardship (AMS) program was implemented to optimize antibiotic use, limit the development of resistance, improve therapeutic efficacy and clinical outcomes, and reduce costs.

METHODS

The stewardship strategies were: antimicrobial oversight on "critical" antibiotics; the development of hospital guidelines on antibiotic selection with the production of a consensus document; the implementation of clinical and management control algorithms with visual impact and Business Intelligence methods; training and updating; and the monitoring of outcome measures and process indicators.

RESULTS

Clinical outcomes: length of stay reduced by 0.23 days, hospital readmission/first month rates decreased by 19%, and mortality for infections reduced by 8.8%. Microbiological Outcomes: Clostridium Difficile colitis incidence reduced by 9.1%.Economic Outcomes: Reduction in antimicrobial costs by 35% on average fee/discharged patient.

CONCLUSIONS

The systematic application of the AMS program in a small hospital led to multiple improvements in clinical, microbiological, and economic outcome measures. The analysis of the core indicators for our hospital AMS program showed a significant adherence to the model and hospital recommendations.

Assessment of Intravenous Antibiotics to Peroral Antibiotics Conversion Practice and Its Associated Factor at University of Gondar Comprehensive Specialized Hospital: Prospective Observational Study

Background

Improper utilization of antibiotics harms the patient, the public, and the economy. The overuse of injections is one of the key factors in the irrational use of medicines. However, little is known about intravenous (IV) to peroral (PO) conversion practice in the Ethiopian healthcare setting, specifically in the Northwest part of Ethiopia.

Objective

To assess antibiotics IV to PO conversion practice and its associated factors at the internal medicine ward of the University of Gondar Comprehensive and Specialized Hospital (UOGCSH).

Method

A prospective observational study was conducted on 324 study participants who were admitted to the University of Gondar Specialized Hospital from October 3 to November 14, 2021. A systematic random sampling technique was employed to select the study participants. Stata version 14.2 was used for the analysis. Descriptive statistics result was presented using mean and standard deviation. Logistic regression analysis was done to determine the association between independent variables and dependent variables. The association between independent variables and dependent variables was tested at 95% CI and P value≤ 0.05 was considered statistical significance.

Result

A total of 324 study participants were included in the study, and the mean age of the patients was 41.4 ± 18.6. Of the 324 study participants, 63.3% were male. The most frequently prescribed antibiotics used for empiric treatment were ceftriaxone (45.4%), followed by metronidazole (33.2%), and cloxacillin (11.4%). A total of 34.5.57% of patients who took antibiotics were converted to PO antibiotics. The most frequently converted type of conversion practice was sequential (23.1%), followed by the switch type of conversion (7.4%). Tachypnea, unavailability of medication, higher temperature, hospital stay greater than 10.78-days, and the presence of comorbidity were predictors of IV medications not being converted to PO medications.

Conclusion

Intravenous to peroral conversion practice was infrequent. The most frequently applied conversion practice was sequential type conversion practice, followed by switch type of conversion practice. IV to PO conversion practice was significantly associated with tachypnea, unavailability of medication, higher temperature, hospital stay greater than 10.78-days, and comorbidity. Awareness of IV to PO conversion practice and short-term training for healthcare teams is vital for better antibiotic conversion practice.

Stevens-Johnson Syndrome Following Vancomycin and Linezolid: A Real-World Analysis of Post-Marketing Surveillance Data

Background: Stevens-Johnson syndrome (SJS) has been reported as a serious adverse effect in patients treated with vancomycin or linezolid, and there is currently a lack of real-world studies comparing specific differences in adverse effects of SJS.

Methods: According to the FDA’s Adverse Event Reporting System (FAERS), from January 2004 to July 2021, the data of suspected SJS after the use of vancomycin and linezolid were analyzed by imbalance and Bayesian analysis. The onset time, fatality rate and hospitalization rate of vancomycin-associated SJS and linezolid-associated SJS were also investigated.

Results: 276 cases of vancomycin-related SJS reports and 63 cases of linezolid-related SJS reports were identified. These two drugs are more common in middle-aged patients (45–64 years) than other age groups, and less common in underage children (<18). Among them, linezolid-related SJS is more common in middle-aged and elderly patients (45–74 years old) than other groups. Except for unspecified data, in vancomycin-associated SJS cases, there are more men than women (49.28% vs 43.84%), while in linezolid-associated SJS cases, the proportion of men and women is almost equal (44.44%). From the point of view of the areas where adverse reactions were reported, about 1/2 of the reports on Vancomycin-related SJS came from North America, and 1/3 of the reports came from Europe. The median onset time of Linezolid-related SJS was 5 days (interquartile range [IQR] 2–7.75), which was significantly earlier than that of Vancomycin-related SJS (12 days, IQR 4–20) (Mann-Whitney test, p < 0.0001). There were no significant differences in mortality and hospitalization rates after vancomycin and linezolid caused SJS.

Conclusion: The analysis of faers data provides a comprehensive overview of the adverse reactions of SJS caused by the use of vancomycin and linezolid, and can warn clinical workers to timely intervene and continuously monitor the patients at risk of SJS when using such drugs.

Existing evidence on antibiotic resistance exposure and transmission to humans from the environment: a systematic map

BACKGROUND

Antimicrobial resistance (AMR) is predicted to become the leading cause of death by 2050 with antibiotic resistance being an important component. Anthropogenic pollution introduces antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) to the natural environment. Currently, there is limited empirical evidence demonstrating whether humans are exposed to environmental AMR and whether this exposure can result in measurable human health outcomes. In recent years there has been increasing interest in the role of the environment and disparate evidence on transmission of AMR to humans has been generated but there has been no systematic attempt to summarise this. We aim to create two systematic maps that will collate the evidence for (1) the transmission of antibiotic resistance from the natural environment to humans on a global scale and (2) the state of antibiotic resistance in the environment in the United Kingdom.

METHODS

Search strategies were developed for each map. Searches were undertaken in 13 bibliographic databases. Key websites were searched and experts consulted for grey literature. Search results were managed using EndNote X8. Titles and abstracts were screened, followed by the full texts. Articles were double screened at a minimum of 10% at both stages with consistency checking and discussion when disagreements arose. Data extraction occurred in Excel with bespoke forms designed. Data extracted from each selected study included: bibliographic information; study site location; exposure source; exposure route; human health outcome (Map 1); prevalence/percentage/abundance of ARB/antibiotic resistance elements (Map 2) and study design. EviAtlas was used to visualise outputs.

RESULTS

For Map 1, 40 articles were included, from 11,016 unique articles identified in searches, which investigated transmission of AMR from the environment to humans. Results from Map 1 showed that consumption/ingestion was the most studied transmission route. Exposure (n = 17), infection (n = 16) and colonisation (n = 11) being studied as an outcome a similar number of times, with mortality studied infrequently (n = 2). In addition, E. coli was the most highly studied bacterium (n = 16). For Map 2, we included 62 studies quantifying ARB or resistance elements in the environment in the UK, from 6874 unique articles were identified in the searches. The most highly researched species was mixed communities (n = 32). The most common methodology employed in this research question was phenotypic testing (n = 37). The most commonly reported outcome was the characterisation of ARBs (n = 40), followed by characterisation of ARGs (n = 35). Other genetic elements, such as screening for intI1 (n = 15) (which encodes a Class 1 integron which is used as a proxy for environmental ARGs) and point mutations (n = 1) were less frequently reported. Both maps showed that research was focused towards aquatic environments.

CONCLUSIONS

Both maps can be used by policy makers to show the global (Map 1) and UK (Map 2) research landscapes and provide an overview of the state of AMR in the environment and human health impacts of interacting with the environment. We have also identified (1) clusters of research which may be used to perform meta-analyses and (2) gaps in the evidence base where future primary research should focus.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1186/s13750-022-00262-2.

Antimicrobial resistance and mcr-1 gene in Escherichia coli isolated from poultry samples submitted to a bacteriology laboratory in South Africa

Background and Aim

Antimicrobial resistance (AMR) and recently mobilized colistin resistance (mcr-1) associated colistin resistance among Escherichia coli isolates have been attributed to the overuse of antimicrobials in livestock production. E. coli remains an important pathogen, often associated with mortality and low carcass weight in poultry medicine; therefore, the need to use antimicrobials is common. The study aimed to determine the AMR profile and presence of mcr-1 and mcr-2 genes in avian pathogenic E. coli from poultry samples tested at a bacteriology laboratory for routine diagnosis. This is a first step in understanding the effectiveness of mitigation strategies.

Materials and Methods

Fifty E. coli strains were assessed for resistance against ten antimicrobial drugs using broth microdilution. All isolates with a colistin minimum inhibitory concentration (MIC) of 2 μg/mL were analyzed for the presence of mcr-1 and mcr-2 genes by employing the polymerase chain reaction. For each isolate, the following farm information was obtained: farm location, type of farm, and on-farm use of colistin.

Results

Sixty-eight percent of the strains were resistant to at least one antimicrobial; 44% were multiple drug-resistant (MDR). Most E. coli isolates were resistant to doxycycline (44%), trimethoprim-sulfamethoxazole (38%), ampicillin (32%), and enrofloxacin (32%). None of the E. coli strains was resistant to colistin sulfate (MIC₉₀ of 2 μg/mL). Only one E. coli isolate held the mcr-1 gene; none carried the mcr-2 gene.

Conclusion

Resistance among E. coli isolates in this study was fairly high. Resistance to commonly used antimicrobials was observed, such as doxycycline, trimethoprim-sulfamethoxazole, and enrofloxacin. Only a single E. coli strain carried the mcr-1 gene, suggesting that mcr-1 and mcr-2 genes are common among isolates in this study. The prevalence of AMR, however, suggests that farmers must implement standard biosecurity measures to reduce E. coli burden, and antimicrobial use to prolong the efficacy life span of some of these drugs.

Clinical outcomes and safety of polymyxin B in the treatment of carbapenem-resistant Gram-negative bacterial infections: a real-world multicenter study

Background

High morbidity and mortality due to carbapenem-resistant Gram-negative bacilli (CR-GNB) has led to the resurgence of polymyxin B (PMB) use in the last decade. The aim of our multicenter, real-world study was to evaluate the effectiveness and safety of PMB in the treatment of CR-GNB infections.

Methods

The real-world study included patients treated with intravenous PMB for at least 7 days during the period of October 2018 through June 2019. Associations between these clinical features and 28-day mortality or all-cause hospital mortality were explored through univariate analyses and multivariable logistic regression.

Results

The study included 100 patients. Many patients presented with combined chronic conditions, septic shock, mechanical ventilation, and the presence of Klebsiella pneumoniae. The mean duration of PMB therapy was 11 days (range 7–38 days). Temperature (38 °C vs 37.1 °C), white blood cells (14.13 × 10⁹/l vs 9.28 × 10⁹/l), C-reactive protein (103.55 ug/l vs 47.60 ug/l), procalcitonin (3.89 ng/ml vs 1.70 ng/ml) and APACHE II levels (17.75 ± 7.69 vs 15.98 ± 7.95) were significantly decreased after PMB treatment. The bacteria eradication rate was 77.65%. The overall mortality at discharge was 15%, and 28-day mortality was 40%. Major adverse reactions occurred in 16 patients. Nephrotoxicity was observed in 7 patients (7%).

Conclusions

Our results provide positive clinical and safety outcomes for PMB in the treatment of CR-GNB. Timely and appropriate use of PMB may be particularly useful in treating patients with sepsis in CR-GNB infections.

Significant Regional Differences in Antibiotic Use Across 576 US Hospitals and 11 701 326 Adult Admissions, 2016-2017

BACKGROUND

Quantifying the amount and diversity of antibiotic use in United States hospitals assists antibiotic stewardship efforts but is hampered by limited national surveillance. Our study aimed to address this knowledge gap by examining adult antibiotic use across 576 hospitals and nearly 12 million encounters in 2016-2017.

METHODS

We conducted a retrospective study of patients aged ≥ 18 years discharged from hospitals in the Premier Healthcare Database between 1 January 2016 and 31 December 2017. Using daily antibiotic charge data, we mapped antibiotics to mutually exclusive classes and to spectrum of activity categories. We evaluated relationships between facility and case-mix characteristics and antibiotic use in negative binomial regression models.

RESULTS

The study included 11 701 326 admissions, totaling 64 064 632 patient-days, across 576 hospitals. Overall, patients received antibiotics in 65% of hospitalizations, at a crude rate of 870 days of therapy (DOT) per 1000 patient-days. By class, use was highest among β-lactam/β-lactamase inhibitor combinations, third- and fourth-generation cephalosporins, and glycopeptides. Teaching hospitals averaged lower rates of total antibiotic use than nonteaching hospitals (834 vs 957 DOT per 1000 patient-days; P < .001). In adjusted models, teaching hospitals remained associated with lower use of third- and fourth-generation cephalosporins and antipseudomonal agents (adjusted incidence rate ratio [95% confidence interval], 0.92 [.86-.97] and 0.91 [.85-.98], respectively). Significant regional differences in total and class-specific antibiotic use also persisted in adjusted models.

CONCLUSIONS

Adult inpatient antibiotic use remains high, driven predominantly by broad-spectrum agents. Better understanding reasons for interhospital usage differences, including by region and teaching status, may inform efforts to reduce inappropriate antibiotic prescribing.

Widespread Use of High-dose Ceftriaxone Therapy for Uncomplicated Gonorrhea Without Reported Ceftriaxone Treatment Failure: Results From 5 Years of Multicenter Surveillance Data in China

BACKGROUND

Antimicrobial resistance to Neisseria gonorrhoeae has emerged for each of the antibiotics recommended as first-line therapies following their introduction into clinical practice. To improve rational and effective clinical antibiotic treatment, we analyzed the prescription patterns of antibiotics and their therapeutic effect in the treatment of uncomplicated gonorrhea in China.

METHODS

We obtained data from a follow-up multicenter surveillance program. Multinomial logistic regression analyses were conducted to explore the associations between demographic/clinical variables with the levels of sensitivity to ceftriaxone and prescription of high-dose ceftriaxone.

RESULTS

In this study, 1686 patients infected with N. gonorrhoeae were recruited in a surveillance network during 1 January 2013 through 31 December 2017 in 7 hospitals distributed in 5 provinces. The prevalence of isolates with decreased susceptibility to ceftriaxone was 9.8% (131/1333), fluctuating between 5.6% and 12.1%. Injectable ceftriaxone was chosen as the first-line treatment among 83.1% of patients, and most of them (72.7% [1018/1401]) received >1000 mg dosage. Patients who were previously infected with gonorrhea or other sexually transmitted infections (adjusted odds ratio [AOR], 1.618 [95% confidence interval {CI}, 1.11-2.358]; AOR, 2.08 [95% CI, 1.41-3.069]) or who already used antibiotics for this infection (AOR, 1.599 [95% CI, 1.041-2.454]) were associated with a higher prescribed ceftriaxone dosage. All of the patients recruited in this study were cured regardless of the isolates' susceptibility to ceftriaxone or the dosage of ceftriaxone they received.

CONCLUSIONS

No ceftriaxone treatment failure for uncomplicated gonorrhea was reported in China; however, high-dose ceftriaxone was widely used in China. Its impacts need further study.

Linking antimicrobial resistance surveillance to antibiotic policy in healthcare settings: the COMBACTE-Magnet EPI-Net COACH project

OBJECTIVES

To systematically summarize the evidence on how to collect, analyse and report antimicrobial resistance (AMR) surveillance data to inform antimicrobial stewardship (AMS) teams providing guidance on empirical antibiotic treatment in healthcare settings.

METHODS

The research group identified 10 key questions about the link between AMR surveillance and AMS using a checklist of 9 elements for good practice in health research priority settings and a modified 3D combined approach matrix, and conducted a systematic review of published original studies and guidelines on the link between AMR surveillance and AMS.

RESULTS

The questions identified focused on AMS team composition; minimum infrastructure requirements for AMR surveillance; organisms, samples and susceptibility patterns to report; data stratification strategies; reporting frequency; resistance thresholds to drive empirical therapy; surveillance in high-risk hospital units, long-term care, outpatient and veterinary settings; and surveillance data from other countries. Twenty guidelines and seven original studies on the implementation of AMR surveillance as part of an AMS programme were included in the literature review.

CONCLUSIONS

The evidence summarized in this review provides a useful basis for a more integrated process of developing procedures to report AMR surveillance data to drive AMS interventions. These procedures should be extended to settings outside the acute-care institutions, such as long-term care, outpatient and veterinary. Without proper AMR surveillance, implementation of AMS policies cannot contribute effectively to the fight against MDR pathogens and may even worsen the burden of adverse events from such interventions.

Cephalosporin Resistance in Escherichia coli Isolated from Children with Septicemia in Mainland China from 2007 to 2017: A Systematic Review and Meta-Analysis

Background: Septicemia in children in mainland China has recently become a public health concern. Methods: A meta-analysis was performed on studies investigating the prevalence of cephalosporin-resistant Escherichia coli isolated from children with septicemia in mainland China from 2007 to 2017 following a search of relevant databases. Results: A total of 43 articles reporting 11 cephalosporins were included in the review. The results of the meta-analysis revealed that for the first-generation cephalosporins, the pooled summarized prevalence of resistance to cefazolin was 74.96% (95% confidence interval [CI]: 64.79-83.91) and cephalothin resistance was 62.28% (95% CI: 36.45-100). Regarding the second-generation cephalosporins, cefoxitin-resistant E. coli comprised 23.85% (95% CI: 10.60-40.40) and cefuroxime resistance was 60.32% (95% CI: 51.25-68.73). For the third-generation cephalosporins, the pooled summarized prevalence of resistance was 51.34% for cefotaxime (95% CI: 40.08-62.54), 40.43% for ceftazidime (95% CI: 31.07-50.15), 45.51% for cefoperazone (95% CI: 20.41-70.61), 12.10% for cefoperazone/sulbactam (95% CI: 6.55-18.76), 62.99% for ceftriaxone (95% CI: 55.00-70.98), and 0% for cefotetan. Among the fourth-generation cephalosporins, resistance to cefepime was 34.08% (95% CI: 25.91-43.31). Conclusions: Most third-generation cephalosporins (e.g., cefotaxime and ceftriaxone) retained high resistance rates throughout the 11-year study period without significant changes. The new fourth-generation cephalosporin, cefepime, is rapidly gaining resistance. Interestingly, ceftazidime, cefepime, and cefoperazone/sulbactam showed a recent decreasing trend of drug resistance. These situations may present a risk for treating children with septicemia and should be closely monitored and treated.

A proposal for a comprehensive approach to infections across the surgical pathway

Despite evidence supporting the effectiveness of best practices in infection prevention and management, many healthcare workers fail to implement them and evidence-based practices tend to be underused in routine practice. Prevention and management of infections across the surgical pathway should always focus on collaboration among all healthcare workers sharing knowledge of best practices. To clarify key issues in the prevention and management of infections across the surgical pathway, a multidisciplinary task force of experts convened in Ancona, Italy, on May 31, 2019, for a national meeting. This document represents the executive summary of the final statements approved by the expert panel.

What is the research evidence for antibiotic resistance exposure and transmission to humans from the environment? A systematic map protocol

BACKGROUND

Antimicrobial resistance (AMR) is a public health crisis that is predicted to cause 10 million deaths per year by 2050. The environment has been implicated as a reservoir of AMR and is suggested to play a role in the dissemination of antibiotic resistance genes (ARGs). Currently, most research has focused on measuring concentrations of antibiotics and characterising the abundance and diversity of ARGs and antibiotic resistant bacteria (ARB) in the environment. To date, there has been limited empirical research on whether humans are exposed to this, and whether exposure can lead to measureable impacts on human health. Therefore, the objective of this work is to produce two linked systematic maps to investigate previous research on exposure and transmission of AMR to humans from the environment. The first map will investigate the available research relating to exposure and transmission of ARB/ARGs from the environment to humans on a global scale and the second will investigate the prevalence of ARB/ARGs in various environments in the UK. These two maps will be useful for policy makers and research funders to identify where there are significant gluts and gaps in the current research, and where more primary and synthesis research needs to be undertaken.

METHODS

Separate search strategies will be developed for the two maps. Searches will be run in 13 databases, and grey literature will be sought from key websites and engagement with experts. Hits will be managed in EndNote and screened in two stages (title/abstract then full text) against predefined inclusion criteria. A minimum of 10% will be double screened with ongoing consistency checking. All included studies will have data extracted into a bespoke form designed and piloted for each map. Data to be extracted will include bibliographic details, study design, location, exposure source, exposure route, health outcome (Map 1); and prevalence/percentage of ARB/ARG (Map 2). No validity appraisal will be undertaken. Results will be tabulated and presented narratively, together with graphics showing the types and areas of research that has been undertaken and heatmaps for key exposure-health outcomes (Map 1) and exposure-prevalence (Map 2).

New potential drug leads against MDR-MTB: A short review

Multidrug resistant Mycobacterium tuberculosis (MDR-MTB) infections have created a critical health problem globally. The appalling rise in drug resistance to all the current therapeutics has triggered the need for identifying new antimycobacterial agents effective against multidrug-resistant Mycobacterium tuberculosis. Structurally unique chemical entities with new mode of action will be required to combat this pressing issue. This review gives an overview of the structures and outlines on various aspects of in vitro pharmacological activities of new antimycobacterial agents, mechanism of action and brief structure activity relationships in the perspective of drug discovery and development. This review also summarizes on recent reports of new antimycobacterial agents.

The Analogs of Temporin-GHa Exhibit a Broader Spectrum of Antimicrobial Activity and a Stronger Antibiofilm Potential against Staphylococcus aureus

The abuse of antibiotics has led to the emergence of multidrug-resistant bacteria, which is becoming a serious worldwide problem people have to face. In our previous study, temporin-GHa (GHa) cloned from Hylarana guentheri showed antimicrobial activity against Gram-positive bacteria. In order to improve its therapeutic potential, we used a template-based and a database-assisted design to obtain three derived peptides by replacing the histidine at both ends of GHa with lysine, which exhibited faster and stronger bactericidal activity and a broader spectrum than the parent peptide. GHaK and GHa4K targeted to the bacterial membrane to exert their antibacterial activities at a faster membrane damage rate. The derived peptides inhibited the initial adhesion and the formation of Staphylococcus aureus biofilms, and eradicated the mature biofilms, which indicated that the derived peptides effectively penetrated the biofilm and killed bacteria. The therapeutic index (TI) and cell selectivity index (CSI) of the derived peptides increased significantly, which means a broader therapeutic window of the derived peptides. The derived peptides with improved activity and cell selectivity have the potential to be the promising candidates for the treatment of S. aureus infections. Our research also provides new insights into the design and development of antimicrobial peptides.

Promising antibacterial agents against multidrug resistant Staphylococcus aureus

Rapid emergence of multidrug resistant Staphylococcus aureus infections has created a critical health menace universally. Resistance to all the available chemotherapeutics has been on rise which led to WHO to stratify Staphylococcus aureus as high tier priorty II pathogen. Hence, discovery and development of new antibacterial agents with new mode of action is crucial to address the multidrug resistant Staphylococcus aureus infections. The egressing understanding of new antibacterials on their biological target provides opportunities for new therapeutic agents. This review underlines on various aspects of drug design, structure activity relationships (SARs) and mechanism of action of various new antibacterial agents and also covers the recent reports on new antibacterial agents with potent activity against multidrug resistant Staphylococcus aureus. This review provides attention on in vitro and in vivo pharmacological activities of new antibacterial agents in the point of view of drug discovery and development.

Synthesis and evaluation of new quinazolin-4(3H)-one derivatives as potent antibacterial agents against multidrug resistant Staphylococcus aureus and Mycobacterium tuberculosis

Staphylococcus aureus and Mycobacterium tuberculosis are major causative agents responsible for serious nosocomial and community-acquired infections impacting healthcare systems globally. Over several decades, these pathogens have developed resistance to multiple antibiotics significantly affecting morbidity and mortality. Thus, these recalcitrant pathogens are amongst the most formidable microbial pathogens for which international healthcare agencies have mandated active identification and development of new antibacterial agents for chemotherapeutic intervention. In our present work, a series of new quinazolin-4(3H)-one derivatives were designed, synthesized and evaluated for their antibacterial activity against ESKAP pathogens and pathogenic mycobacteria. The experiments revealed that 4'c, 4'e, 4'f and 4'h displayed selective and potent inhibitory activity against Staphylococcus aureus with MIC values ranging from 0.03-0.25 μg/mL. Furthermore, compounds 4'c and 4'e were found to be benign to Vero cells (CC₅₀ = >5 μg/mL) and displayed promising selectivity index (SI) > 167 and > 83.4 respectively. Additionally, 4'c and 4'e demonstrated equipotent MIC against multiple drug-resistant strains of S. aureus including VRSA, concentration dependent bactericidal activity against S. aureus and synergized with FDA approved drugs. Moreover, compound 4'c exhibited more potent activity in reducing the biofilm and exhibited a PAE of ∼2 h at 10X MIC which is comparable to levofloxacin and vancomycin. In vivo efficacy of 4'c in murine neutropenic thigh infection model revealed that 4'c caused a similar reduction in cfu as vancomycin. Gratifyingly, compounds 4d, 4e, 9a, 9b, 14a, 4'e and 4'f also exhibited anti-mycobacterial activity with MIC values in the range of 2-16 μg/mL. In addition, the compounds were found to be less toxic to Vero cells (CC₅₀ = 12.5->100 μg/mL), thus displaying a favourable selectivity index. The interesting results obtained here suggest the potential utilization of these new quinazolin-4(3H)-one derivatives as promising antibacterial agents for treating MDR-Staphylococcal and mycobacterial infections.

Clinical Prediction Score for Community-Onset Bloodstream Infections Caused by Extended-Spectrum Beta-Lactamase-Producing Escherichia coli and Klebsiella Species

BACKGROUND

This study aimed to identify the predictors and build a prediction score for community-onset bloodstream infections (CO-BSIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella species.

METHODS

All CO-BSIs caused by E. coli and Klebsiella species from 2012 to 2015 were grouped into derivation (BSIs from 2012 to 2014) and validation (BSIs in 2015) cohorts. A prediction score was built using the coefficients of the multivariate logistic regression model from the derivation cohort.

RESULTS

The study included 886 CO-BSIs (594 and 292 in the derivation and validation cohorts, respectively). The independent predictors of CO-BSIs caused by ESBL-producing E. coli and Klebsiella species included: 1) identification of ESBL-producing microorganisms from any clinical culture within one year of admission, 2) beta-lactam or fluoroquinolone treatment within 30 days (with 2 or more courses within 90 days; with 1 course within 90 days), 3) hospitalization within one year, 4) the presence of an indwelling urinary catheter at the time of admission. The area under the curve (AUC) of the clinical prediction score was 0.72 (95% confidence interval [CI], 0.68-0.77). In the validation cohort, the AUC was 0.70 (95% CI, 0.63-0.77).

CONCLUSIONS

The results of this study suggest a simple and easy-to-use scoring system to predict CO-BSIs caused by ESBL-producing E. coli and Klebsiella species.

Antimicrobial Resistance Surveillance and New Drug Development

Surveillance represents an important informational tool for planning actions to monitor emerging antimicrobial resistance. Antimicrobial resistance surveillance (ARS) programs may have many different designs and can be grouped in 2 major categories based on their main objectives: (1) public health ARS programs and (2) industry-sponsored/product-oriented ARS programs. In general, public health ARS programs predominantly focus on health care and infection control, whereas industry ARS programs focus on an investigational or recently approved molecule(s). We reviewed the main characteristics of industry ARS programs and how these programs contribute to new drug development. Industry ARS programs are generally performed to comply with requirements from regulatory agencies responsible for commercial approval of antimicrobial agents, such as the US Food and Drug Administration, European Medicines Agency, and others. In contrast to public health ARS programs, which typically collect health care and diverse clinical data, industry ARS programs frequently collect the pathogens and perform the testing in a central laboratory setting. Global ARS programs with centralized testing play an important role in new antibacterial and antifungal drug development by providing information on the emergence and dissemination of resistant organisms, clones, and resistance determinants. Organisms collected by large ARS programs are extremely valuable to evaluate the potential of new agents and to calibrate susceptibility tests once a drug is approved for clinical use. These programs also can provide early evaluations of spectrum of activity and postmarketing trends required by regulatory agencies, and the programs may help drug companies to select appropriate dosing regimens and the appropriate geographic regions in which to perform clinical trials. Furthermore, these surveillance programs provide useful information on the potency and spectrum of new antimicrobial agents against indications and organisms in which clinicians have little or no experience. In summary, large ARS programs, such as the SENTRY Antimicrobial Surveillance Program, contribute key data for new drug development.

Host adaptation and convergent evolution increases antibiotic resistance without loss of virulence in a major human pathogen

As human population density and antibiotic exposure increase, specialised bacterial subtypes have begun to emerge. Arising among species that are common commensals and infrequent pathogens, antibiotic-resistant 'high-risk clones' have evolved to better survive in the modern human. Here, we show that the major matrix porin (OmpK35) of Klebsiella pneumoniae is not required in the mammalian host for colonisation, pathogenesis, nor for antibiotic resistance, and that it is commonly absent in pathogenic isolates. This is found in association with, but apparently independent of, a highly specific change in the co-regulated partner porin, the osmoporin (OmpK36), which provides enhanced antibiotic resistance without significant loss of fitness in the mammalian host. These features are common in well-described 'high-risk clones' of K. pneumoniae, as well as in unrelated members of this species and similar adaptations are found in other members of the Enterobacteriaceae that share this lifestyle. Available sequence data indicate evolutionary convergence, with implications for the spread of lethal antibiotic-resistant pathogens in humans.

4(3H)-Quinazolinone derivatives: Promising antibacterial drug leads

Emergence of drug resistance has created unmet medical need for the development of new classes of antibiotics. Discovery of new antibacterial agents with new mode of action remains a high priority universally. 4(3H)-quinazolinone, a fused nitrogen heterocyclic compound has emerged as a biologically privileged structure, possessing a wide range of biological properties viz. anticancer, antibacterial, antitubercular, antifungal, anti-HIV, anticonvulsant, anti-inflammatory and analgesic activities. Promising antibacterial properties of quinazolinones have enthused the medicinal chemists to explore and develop this fused heterocyclic system for new antibacterial agents. Utilization of quinazolinone core for the design and synthesis of new antibacterial agents has recently gained momentum. This review aims to provide an overview of the structures and antibacterial activity of various 4(3H)-quinazolinone derivatives covering various aspects of in vitro and in vivo pharmacological activities and structure activity relationships (SARs).

Evaluating the Bioactivity of a Novel Broad-Spectrum Antimicrobial Peptide Brevinin-1GHa from the Frog Skin Secretion of Hylarana guentheri and Its Analogues

Many antimicrobial peptides (AMPs) have been identified from the skin secretion of the frog Hylarana guentheri (H.guentheri), including Temporin, Brevinin-1, and Brevinin-2. In this study, an antimicrobial peptide named Brevinin-1GHa was identified for the first time by using ‘shotgun’ cloning. The primary structure was also confirmed through mass spectral analysis of the skin secretion purified by reversed-phase high-performance liquid chromatography (RP-HPLC). There was a Rana-box (CKISKKC) in the C-terminal of Brevinin-1GHa, which formed an intra-disulfide bridge. To detect the significance of Rana-box and reduce the hemolytic activity, we chemically synthesized Brevinin-1GHb (without Rana-box) and Brevinin-1GHc (Rana-box in central position). Brevinin-1GHa exhibited a strong and broad-spectrum antimicrobial activity against seven microorganisms, while Brevinin-1GHb only inhibited the growth of Staphylococcus aureus (S. aureus), which indicates Rana-box was necessary for the antimicrobial activity of Brevinin-1GHa. The results of Brevinin-1GHc suggested transferring Rana-box to the central position could reduce the hemolytic activity, but the antimicrobial activity also declined. Additionally, Brevinin-1GHa demonstrated the capability of permeating cell membrane and eliminating biofilm of S. aureus, Escherichia coli (E. coli), and Candida albicans (C. albicans). The discovery of this research may provide some novel insights into natural antimicrobial drug design.

Synthesis of 1,2,3-triazole linked 4(3H)-Quinazolinones as potent antibacterial agents against multidrug-resistant Staphylococcus aureus

Methicillin and vancomycin resistant Staphylococcus aureus infections are an emerging global health concern leading to increasing morbidity and mortality. Continuous increase in drug resistance has underlined the need for discovery and development of new antibacterial agents acting via novel mechanisms to overcome this pressing issue. In this context, a number of 1,2,3-triazole linked 4(3H)-quinazolinone derivatives were designed and synthesized as potent antibacterial agents. When evaluated against ESKAP pathogen panel, compounds 7a, 7b, 7c, 7e, 7f, 7g, 7h, 7i, 9a, 9c, 9d and 9e exhibited significantly selective inhibitory activities towards Staphylococcus aureus (MIC = 0.5-4 μg/mL). To understand and confirm the specificity of these compounds, the compounds 7a and 9a were tested against E. coli and A. baumannii in combination with sub-lethal concentrations of Polymyxin B nonapeptide (PMBN) and were found to be inactive. This clearly indicated that these compounds possess specific and potent activity towards S. aureus and are inactive against gram-negative pathogens. Encouragingly, the compounds were also found to be non toxic to Vero cells and displayed favourable selectivity index (SI = 40 to 80). Furthermore, 7a and 9a were found to possess potent inhibitory activity when tested against multidrug resistant S. aureus including strains resistant to vancomycin (MIC values 0.5-32 μg/mL), indicating that the compounds are able to escape current drug-resistance mechanisms. With the potent anti-bacterial activity exhibited the new series of 1,2,3-triazole linked 4(3H)-quinazolinones have emerged as promising candidates for treating multidrug resistant Staphylococcus aureus infections.

Hospital-Level Variability in Broad-Spectrum Antibiotic Use for Children With Acute Leukemia Undergoing Hematopoietic Cell Transplantation

OBJECTIVETo explore the prevalence and drivers of hospital-level variability in antibiotic utilization among hematopoietic cell transplant (HCT) recipients to inform antimicrobial stewardship initiatives.DESIGNRetrospective cohort study using data merged from the Pediatric Health Information System and the Center for International Blood and Marrow Transplant Research.SETTINGThe study included 27 transplant centers in freestanding children's hospitals.METHODSThe primary outcome was days of broad-spectrum antibiotic use in the interval from day of HCT through neutrophil engraftment. Hospital antibiotic utilization rates were reported as days of therapy (DOTs) per 1,000 neutropenic days. Negative binomial regression was used to estimate hospital utilization rates, adjusting for patient covariates including demographics, transplant characteristics, and severity of illness. To better quantify the magnitude of hospital variation and to explore hospital-level drivers in addition to patient-level drivers of variation, mixed-effects negative binomial models were also constructed.RESULTSAdjusted hospital rates of antipseudomonal antibiotic use varied from 436 to 1121 DOTs per 1,000 neutropenic days, and rates of broad-spectrum, gram-positive antibiotic use varied from 153 to 728 DOTs per 1,000 neutropenic days. We detected variability by hospital in choice of antipseudomonal agent (ie, cephalosporins, penicillins, and carbapenems), but gram-positive coverage was primarily driven by vancomycin use. Considerable center-level variability remained even after controlling for additional hospital-level factors. Antibiotic use was not strongly associated with days of significant illness or mortality.CONCLUSIONAmong a homogenous population of children undergoing HCT for acute leukemia, both the quantity and spectrum of antibiotic exposure in the immediate posttransplant period varied widely. Antimicrobial stewardship initiatives can apply these data to optimize the use of antibiotics in transplant patients.Infect Control Hosp Epidemiol 2018;797-805.

A retrospective evaluation of blood cultures in a pediatric intensive care unit: a three year evaluation

AIM

In this study, it was aimed to retrospectively assess the frequency and antibiotic resistance of microorganisms isolated from blood cultures of patients in a pediatric intensive care unit.

MATERIAL AND METHODS

The study was conducted on blood culture tests obtained from patients in a pediatric intensive care unit and sent to a microbiology laboratory between 2013 and 2016. The species and antibiotic susceptibilities were assessed in microorganisms isolated from the blood cultures.

RESULTS

Overall, 4239 blood cultures were obtained. Growth was detected in 324 blood cultures (7.6%). Of the microorganisms isolated, 195 (60.2%) were Gram-positive bacteria, and 107 (33.0%) were Gram-negative bacteria; 22 (6.8%) were fungi. The most commonly isolated microorganisms were Coagulase-negative staphylococci (45.1%), followed by Klebsiella pneumonia (14.5%), and Enterococcus faecalis (6.5%). Among the fungi, the most common was Candida albicans (59.1%), followed by Candida parapsilosis. The resistance rate against methicillin was 89.9% in coagulase-negative staphylococci, and 66% in S. aureus strains. The resistance rate against vancomycin was 3.6% in Enterococci spp. There was no resistance against linezolid in Gram-positive microorganisms. The rate of extended-spectrum beta lactamase positivity was found as 34% in Klebsiella spp. and 100% in Escherichia coli. The resistance rate against carbapenem was 44.9% in Gram-negative bacteriae. The resistance rate against carbapenem was 100% in Acinetobacter baumanii. In Candida albicans, resistance to amphotericine B was 61.5%, and resistance to voriconazole was 7.7%.

CONCLUSIONS

To plan effective empiric antibiotic therapy against nosocomial infections in intensive care units, all units should have information about the characteristics of their own flora.

Antibiotic-Stewardship Practices at Top Academic Centers Throughout the United States and at Hospitals Throughout Massachusetts

Objective.

Improvements in antibiotic prescribing to reduce bacterial resistance and control hospital costs is a growing priority, but the way to accomplish this is poorly defined. Our goal was to determine whether certain antibiotic stewardship interventions were universally instituted and accepted at top US academic centers and to document what interventions, if any, are used at both teaching and community hospitals within a geographic area.

Design.

Two surveys were conducted. In survey 1, detailed phone interviews were performed with the directors of antibiotic stewardship programs at 22 academic medical centers that are considered among the best for overall medical care in the United States or as leaders in antibiotic stewardship programs. In survey 2, teaching and community hospitals throughout Massachusetts were surveyed to ascertain what antibiotic oversight program components were present.

Results.

In survey 1, each of the 22 participating hospitals had instituted interventions to improve antibiotic prescribing, but none of the interventions were universally accepted as essential or effective. In survey 2, of 97 surveys that were mailed to prospective participants, a total of 54 surveys from 19 teaching hospitals and 35 community hospitals were returned. Ninety-five percent of the teaching hospitals had a restricted formulary, compared with 49% of the community hospitals, and 89% of teaching hospitals had an antibiotic approval process, compared with 29% of community hospitals.

Conclusion.

There was great variability among the approaches to the oversight of antibiotic prescribing at major academic hospitals. Antibiotic management interventions were lacking in more than half of the Massachusetts community hospitals surveyed. More research is needed to define the best antibiotic stewardship interventions for different hospital settings.

Pathogens and antimicrobial susceptibility profiles in critically ill patients with bloodstream infections: a descriptive study

BACKGROUND

Surveillance of antimicrobial resistance is vital to guiding empirical treatment of infections. Collating and reporting routine data on clinical isolate testing may offer more timely information about resistance patterns than traditional surveillance network methods.

METHODS

Using routine microbiology testing data collected from the Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness retrospective cohort study, we conducted a descriptive secondary analysis among critically ill patients in whom bloodstream infections had been diagnosed in 14 intensive care units (ICUs) in Canada. The participating sites were located within tertiary care teaching hospitals and represented 6 provinces and 10 cities. More than 80% of the study population was accrued from 2011-2013. We assessed the epidemiologic features of the infections and corresponding antimicrobial susceptibility profiles. Susceptibility testing was done according to Clinical Laboratory Standards Institute guidelines at accredited laboratories.

RESULTS

A total of 1416 pathogens were isolated from 1202 patients. The most common organisms were Escherichia coli (217 isolates [15.3%]), Staphylococcus aureus (175 [12.4%]), coagulase-negative staphylococci (117 [8.3%]), Klebsiella pneumoniae (86 [6.1%]) and Streptococcus pneumoniae (85 [6.0%]). The contribution of individual pathogens varied by site. For 13 ICUs, gram-negative susceptibility rates were high for carbapenems (95.4%), tobramycin (91.2%) and piperacillin-tazobactam (90.0%); however, the proportion of specimens susceptible to these agents ranged from 75.0%-100%, 66.7%-100% and 75.0%-100%, respectively, across sites. Fewer gram-negative bacteria were susceptible to fluoroquinolones (84.5% [range 64.1%-97.2%]). A total of 145 patients (12.1%) had infections caused by highly resistant microorganisms, with significant intersite variation (range 2.6%-24.0%, χ2 = 57.50, p < 0.001).

INTERPRETATION

We assessed the epidemiologic features of bloodstream infections in a geographically diverse cohort of critically ill Canadian patients using routine pathogen and susceptibility data extracted from readily available microbiology testing databases. Expanding data sharing across more ICUs, with serial measurement and prompt reporting, could provide much-needed guidance for empiric treatment for patients as well as system-wide prevention methods to limit antimicrobial resistance.

Guidance on the Selection of Appropriate Indicators for Quantification of Antimicrobial Usage in Humans and Animals

An increasing variety of indicators of antimicrobial usage has become available in human and veterinary medicine, with no consensus on the most appropriate indicators to be used. The objective of this review is therefore to provide guidance on the selection of indicators, intended for those aiming to quantify antimicrobial usage based on sales, deliveries or reimbursement data. Depending on the study objective, different requirements apply to antimicrobial usage quantification in terms of resolution, comprehensiveness, stability over time, ability to assess exposure and comparability. If the aim is to monitor antimicrobial usage trends, it is crucial to use a robust quantification system that allows stability over time in terms of required data and provided output; to compare usage between different species or countries, comparability must be ensured between the different populations. If data are used for benchmarking, the system comprehensiveness is particularly crucial, while data collected to study the association between usage and resistance should express the exposure level and duration as a measurement of the exerted selection pressure. Antimicrobial usage is generally described as the number of technical units consumed normalized by the population at risk of being treated in a defined period. The technical units vary from number of packages to number of individuals treated daily by adding different levels of complexity such as daily dose or weight at treatment. These technical units are then related to a description of the population at risk, based either on biomass or number of individuals. Conventions and assumptions are needed for all of these calculation steps. However, there is a clear lack of standardization, resulting in poor transparency and comparability. By combining study requirements with available approaches to quantify antimicrobial usage, we provide suggestions on the most appropriate indicators and data sources to be used for a given study objective.

The global epidemiology of carbapenemase-producing Enterobacteriaceae

Carbapenemase-producing Enterobacteriaceae (CPE) are an important and increasing threat to global health. Both clonal spread and plasmid-mediated transmission contribute to the ongoing rise in incidence of these bacteria. Among the 4 classes of β-lactamases defined by the Ambler classification system, the carbapenemases that confer carbapenem resistance in Enterobacteriaceae belong to 3 of them: Class A (K. pneumoniae carbapenemases, KPC), Class B (metallo-β-lactamases, MBL including New Delhi metallo-β-lactamases, NDM) and Class D (OXA-48-like carbapenemases). KPC-producing CPE are the most commonly occurring CPE in the United States. MBL-producing CPE have been most commonly associated with the Indian Subcontinent as well as with specific countries in Europe, including Romania, Denmark, Spain, and Hungary. The epicenter of OXA-48-like-producing is in Turkey and surrounding countries. Detailed knowledge of the epidemiology and molecular characteristics of CPE is essential to stem the spread of these pathogens.

Systematic Review and Meta-analysis of Clinical and Economic Outcomes from the Implementation of Hospital-Based Antimicrobial Stewardship Programs

The implementation of antimicrobial stewardship programs (ASPs) is a promising strategy to help address the problem of antimicrobial resistance. We sought to determine the efficacy of ASPs and their effect on clinical and economic parameters. We searched PubMed, EMBASE, and Google Scholar looking for studies on the efficacy of ASPs in hospitals. Based on 26 studies (extracted from 24,917 citations) with pre- and postimplementation periods from 6 months to 3 years, the pooled percentage change of total antimicrobial consumption after the implementation of ASPs was -19.1% (95% confidence interval [CI] = -30.1 to -7.5), and the use of restricted antimicrobial agents decreased by -26.6% (95% CI = -52.3 to -0.8). Interestingly, in intensive care units, the decrease in antimicrobial consumption was -39.5% (95% CI = -72.5 to -6.4). The use of broad-spectrum antibiotics (-18.5% [95% CI = -32 to -5.0] for carbapenems and -14.7% [95% CI = -27.7 to -1.7] for glycopeptides), the overall antimicrobial cost (-33.9% [95% CI = -42.0 to -25.9]), and the hospital length of stay (-8.9% [95% CI = -12.8 to -5]) decreased. Among hospital pathogens, the implementation of ASPs was associated with a decrease in infections due to methicillin-resistant Staphylococcus aureus (risk difference [RD] = -0.017 [95% CI = -0.029 to -0.005]), imipenem-resistant Pseudomonas aeruginosa (RD = -0.079 [95% CI = -0.114 to -0.040]), and extended-spectrum beta-lactamase Klebsiella spp. (RD = -0.104 [95% CI = -0.153 to -0.055]). Notably, these improvements were not associated with adverse outcomes, since the all-cause, infection-related 30-day mortality and infection rates were not significantly different after implementation of an ASP (RD = -0.001 [95% CI = -0.009 to 0.006], RD = -0.005 [95% CI = -0.016 to 0.007], and RD = -0.045% [95% CI = -0.241 to 0.150], respectively). Hospital ASPs result in significant decreases in antimicrobial consumption and cost, and the benefit is higher in the critical care setting. Infections due to specific antimicrobial-resistant pathogens and the overall hospital length of stay are improved as well. Future studies should focus on the sustainability of these outcomes and evaluate potential beneficial long-term effects of ASPs in mortality and infection rates.

Methicillin-ResistantStaphylococcus aureusin German Intensive Care Units During 2000-2003: Data from Project SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in Intensive Care Units)

Objectives.

The objective of this study was to analyze methicillin-resistantStaphylococcus aureus(MRSA) percentages (defined as the percentage ofS. aureusisolates that are resistant to methicillin) and antimicrobial consumption in intensive care units (ICUs) participating in Project SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in Intensive Care Units), to look for temporal changes in MRSA percentages and antimicrobial consumption in individual ICUs as an indicator of the impact of an active surveillance system, and to investigate the differences between ICUs with increased MRSA percentages versus those with decreased percentages during a period of 3 years (2001-2003).

Methods.

This was a prospective, ICU-based and laboratory-based surveillance study involving 38 German ICUs during 2000-2003. Antimicrobial use was reported in terms of defined daily doses (DDDs) per 1,000 patient-days. Temporal changes in the MRSA percentage and antimicrobial use in individual ICUs were calculated by means of the Wilcoxon signed rank test. The incidence density of nosocomial MRSA infection was defined as the number of nosocomial MRSA infections per 1,000 patient-days.

Results.

From February 2000 through December 2003, a total of 38 ICUs reported data on 499,694 patient-days and 9,552S. aureusisolates, including 2,249 MRSA isolates and 660,029 DDDs of antimicrobials. Cumulative MRSA percentages ranged from 0% to 64.4%, with a mean of 23.6%. The MRSA incidence density ranged from 0 to 38.2 isolates per 1,000 patient-days, with a mean of 2.77 isolates per 1,000 patient-days. There was a positive correlation between MRSA percentage and imipenem and ciprofloxacin use (P<.05). Overall, comparison of data from 2001 with data from 2003 showed that MRSA percentages increased in 18 ICUs (median increase, 13.2% [range, 1.6%-38.4%]) and decreased in 14 ICUs (median decrease, 12% [range, 1.0%-48.4%]). Increased use of third-generation cephalosporins, glycopeptides, or aminoglycosides correlated significantly with an increase in the MRSA percentage (P<.05). The cumulative nosocomial MRSA infection incidence density for 141 ICUs that did not participate in SARI and, therefore, did not receive feedback increased from 0.26 to 0.35 infections per 1,000 patient-days during a 3-year period, whereas the rate in SARI ICUs decreased from 0.63 to 0.40 infections per 1,000 patient-days.

Conclusion.

The MRSA situation in German ICUs is still heterogeneous. Because MRSA percentages range from 0% to 64.4%, further studies are required to confirm findings that no change in the MRSA percentage and a decrease in the nosocomial MRSA infection incidence density in SARI ICUs reflect the impact of an active surveillance system.

Antimicrobial Use Control Measures to Prevent and Control Antimicrobial Resistance in US Hospitals

Objective.

Clinical practice guidelines and recommended practices to control use of antibiotics have been published, but the effect of these practices on antimicrobial resistance (AMR) rates in hospitals is unknown. The objective of this study was to examine relationships between antimicrobial use control strategies and AMR rates in a national sample of US hospitals.

Design.

Cross-sectional, stratified study of a nationally representative sample of US hospitals.

Methods.

A survey instrument was sent to the person responsible for infection control at a sample of 670 US hospitals. The outcome was current prevalences of 4 epidemiologically important, drug-resistant pathogens, considered concurrently: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, ceftazidime-resistant Klebsiella species, and quinolone (ciprofloxacin)-resistant Escherichia coli Five independent variables regarding hospital practices were selected from the survey: the extent to which hospitals (1) implement practices recommended in clinical practice guidelines and ensure best practices for antimicrobial use, (2) disseminate information on clinical practice guidelines for antimicrobial use, (3) use antimicrobial-related information technology, (4) use decision support tools, and (5) communicate to prescribers about antimicrobial use. Control variables included the hospitals' number of beds, teaching status, Veterans Affairs status, geographic region, and number of long-term care beds; and the presence of an intensive care unit, a burn unit, or transplant services. A generalized estimating equation modeled all resistance rates simultaneously to identify overall predictors of AMR levels at the facility.

Results.

Completed survey instruments were returned by 448 hospitals (67%). Four antimicrobial control measures were associated with higher prevalence of AMR. Implementation of recommended practices for antimicrobial use (P< .01) and optimization of the duration of empirical antibiotic prophylaxis (P<.01) were associated with a lower prevalence of AMR. Use of restrictive formularies (P = .05) and dissemination of clinical practice guideline information (P<.01) were associated with higher prevalence of AMR. Number of beds and Veterans Affairs status were also associated with higher AMR rates overall.

Conclusions.

Implementation of guideline-recommended practices to control antimicrobial use and optimize the duration of empirical therapy appears to help control AMR rates in US hospitals. A longitudinal study would confirm the results of this cross-sectional study. These results highlight the need for systems interventions and reengineering to ensure more-consistent application of guideline-recommended measures for antimicrobial use.

Importance of Control Group Selection for Evaluating Antimicrobial Use as a Risk Factor for Methicillin-ResistantStaphylococcus AureusBacteremia

Objective:

We investigated the importance of control group selection during an evaluation of antimicrobial use as a risk factor for methicillin-resistantStaphylococcus aureus(MRSA) bacteremia at our institution.

Methods:

We performed a case-control study. A case was defined as any patient admitted between January 1997 and May 2001 who developed nosocomial MRSA bacteremia. We used two control groups; control group I consisted of patients with nosocomial methicillin-susceptibleS. aureus(MSSA) bacteremia and control group II included only patients without bacteremia. We matched control-patients to case-patients using age, gender, time at risk, and hospital ward. Data collected on all patients included demographics, comorbidities, antibiotic use, time at risk, length of stay, severity of illness, and outcome.

Results:

We evaluated 63 patients (21 in each group). The three groups were well matched regarding age, gender, underlying diseases, and severity of illness. Patients in the MRSA group were more likely to have received a fluoroquinolone and had a higher mean number of days of fluoroquinolone use than did patients in the MSSA group (P= .027 andP= .015, respectively). However, all measures of fluoroquinolone use were similar for case-patients and for control-patients who did not have nosocomial bloodstream infection.

Conclusions:

Control group selection is important in evaluating antimicrobial use as a risk factor for MRSA bacteremia. Using control-patients infected with MSSA, rather than uninfected control-patients, may overestimate the association between antimicrobial use and MRSA infection. (Infect Control Hosp Epidemiol 2005;26:634-637)

When Antimicrobial Stewardship Isn't Watching: The Educational Impact of Critical Care Prospective Audit and Feedback

Prospective audit and feedback (PAF) is an effective strategy to optimize antimicrobial use in the critical care setting, yet whether skills gained during PAF influence future antimicrobial prescribing is uncertain. This multisite study demonstrates that knowledge learned during PAF is translated and incorporated into the practice of critical care physicians even when not supported by an antimicrobial stewardship program.

Unnecessary Antibiotics for Acute Respiratory Tract Infections: Association With Care Setting and Patient Demographics

Background.  Up to 40% of antibiotics are prescribed unnecessarily for acute respiratory tract infections (ARTIs). We sought to define factors associated with antibiotic overprescribing of ARTIs to inform efforts to improve practice. Methods.  We conducted a retrospective analysis of ARTI visits between 2006 and 2010 from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey. Those surveys provide a representative sample of US visits to community-based physicians and to hospital-based emergency departments (EDs) and outpatient practices. Patient factors (age, sex, race, underlying lung disease, tobacco use, insurance), physician specialty, practice demographics (percentage poverty, median household income, percentage with a Bachelor's Degree, urban-rural status, geographic region), and care setting (ED, hospital, or community-based practice) were evaluated as predictors of antibiotic overprescribing for ARTIs. Results.  Hospital and community-practice visits had more antibiotic overprescribing than ED visits (odds ratio [OR] = 1.64 and 95% confidence interval [CI], 1.27-2.12 and OR = 1.59 and 95% CI, 1.26-2.01, respectively). Care setting had significant interactions with geographic region and urban and rural location. The quartile with the lowest percentage of college-educated residents had significantly greater overprescribing (adjusted OR = 1.41; 95% CI, 1.07-1.86) than the highest quartile. Current tobacco users were overprescribed more often than nonsmokers (OR = 1.71; 95% CI, 1.38-2.12). Patient age, insurance, and provider specialty were other significant predictors. Conclusions.  Tobacco use and a lower grouped rate of college education were associated with overprescribing and may reflect poor health literacy. A focus on educating the patient may be an effective approach to stewardship.

Trends of Antibiotic Consumption in Korea According to National Reimbursement Data (2008-2012): A Population-Based Epidemiologic Study

This study determined the trends in the quantities and patterns of nationwide antibiotic consumption in the Republic of Korea (ROK).This nationwide descriptive epidemiological study was conducted in the ROK between 2008 and 2012. The quantities and patterns of total systemic antibiotic prescriptions were analyzed using National Health Insurance claims data collected through the Health Insurance Review and Assessment service. Data concerning systemic antibiotics were collected using measurement units of the defined daily dose (DDD) per 1000 people per day according to the Anatomical Therapeutic Chemical classification.Over the 5-year study period, the annual consumption of systemic antibiotics ranged from 21.68 to 23.12 DDD per 1000 people per day. Outpatient antibiotic use accounted for 80.9% of total consumption. A regression model with autoregressive errors showed significant increased consumption of major antibiotic subgroups, including 3rd-generation cephalosporins, carbapenems, and glycopeptides (P < 0.001). However, the antibiotic use of 1st- (P = 0.003), 2nd- (P = 0.004), and 3rd-generation (P = 0.018) cephalosporins among patients who underwent surgery under monitoring by the antimicrobial stewardship programs for perioperative prescription was significantly lower than in those who underwent surgery without monitoring programs. In time-series analysis, total antibiotic consumption demonstrated significant seasonality (P < 0.001).The consumption of broad-spectrum antibiotics was noted to have increased in the ROK from 2008 to 2012, providing a possible explanation for the changing epidemiology of multidrug resistance. Larger prospective studies are needed to investigate the impact on public health of monitoring programs of perioperative antibiotic usage.

Antibiotics for respiratory tract infections: a comparison of prescribing in an outpatient setting

OBJECTIVE

To examine inappropriate antibiotic prescribing for acute respiratory tract infections (RTIs) in ambulatory care to help target antimicrobial stewardship interventions. Design and Setting Retrospective analysis of RTI visits within general internal medicine (GIM) and family medicine (FM) ambulatory practices at an inner-city academic medical center from 2008 to 2010.

METHODS

Patient, physician, and practice characteristics were analyzed using multivariable logistic regression to determine factors predictive of inappropriate prescribing; physicians in the highest and lowest antibiotic-prescribing quartiles were compared using χ2 analysis.

RESULTS

Visits with FM providers, female gender, and self-reported race/ethnicity as white or Hispanic were significantly associated with inappropriate antibiotic prescribing. Physicians in the lowest quartile prescribed antibiotics for 5%-28% (mean, 21%) of RTI visits; physicians in the highest quartile prescribed antibiotics for 54%-85% (mean, 65%) of RTI visits. High prescribers had fewer African-American patients and more patients who were younger and privately insured. High prescribers had more patients with chronic lung disease. A GIM practice pod with a low prescriber was 3.0 times more likely to have a second low prescriber than other practice pods, whereas pods with a high prescriber were 1.3 times more likely to have a second high prescriber.

CONCLUSIONS

Medical specialty was the only physician factor predictive of inappropriate prescribing when patient gender, race, and comorbidities were taken into account. Possible disparities in care need further study. Stewardship education in medical school, enlisting low prescribers as physician leaders, and targeting interventions to the highest prescribers might be more effective approaches to antimicrobial stewardship.

A Qualitative Analysis of Implementation of Antimicrobial Stewardship at 3 Academic Hospitals: Understanding the Key Influences on Success

BACKGROUND

Inappropriate use of antimicrobials is linked to the development and spread of drug-resistant pathogens and is associated with increased morbidity, mortality, lengths of hospital stay, and health care costs. "Antimicrobial stewardship" is the umbrella term for an evidence-based knowledge translation strategy involving comprehensive quality improvement activities to optimize the use of antimicrobials, improve patient outcomes, reduce the development of antimicrobial resistance and hospital-acquired infections such as Clostridium difficile, and decrease health care costs.

OBJECTIVE

To assess the perceptions and experiences of antimicrobial stewardship program leaders in terms of clinicians' attitudes toward and behaviours related to antimicrobial prescribing.

METHODS

In this qualitative study, semistructured interviews were conducted with 6 antimicrobial stewards (2 physicians and 4 pharmacists) at 3 academic hospitals between June and August 2013.

RESULTS

The following 3 key themes emerged from the interviews: getting the right people on board, building collegial relationships, and rapidly establishing a track record. The study results elucidated the role and mechanisms that the program leader and other antimicrobial stewards used to influence other clinicians to engage in effective utilization of antimicrobials. The results also highlighted the methods employed by members of the antimicrobial stewardship team to tailor their strategies to the local context and to stakeholders of participating units; to gain credibility by demonstrating the impact of the antimicrobial stewardship program on clinical outcomes and cost; and to engage senior leaders to endorse and invest in the antimicrobial stewardship program, thereby adding to the antimicrobial stewards' credibility and their ability to influence the uptake of effective antimicrobial use.

CONCLUSIONS

Collectively, these results offer insight into processes and mechanisms of influence employed by antimicrobial stewards to enhance antimicrobial use among clinicians, which can in turn inform future implementation of antimicrobial stewardship and strategies for organizational change in hospitals.

SeverePseudomonas aeruginosainfections

Pseudomonas aeruginosa infections are a frequent cause of morbidity and mortality in hospitalized patients. Treatment of these infections is complicated by the intrinsic and acquired resistance of this bacterium to many commonly used antimicrobial agents. In this article, Drs Hauser and Sriram argue that careful consideration of the mechanisms by which P. aeruginosa resists the activity of antimicrobial agents is essential for optimal treatment decisions. Although many aspects of treatment of severe P. aeruginosa infections remain controversial, the authors suggest specific treatment options for patients both before and after susceptibilities are known.