Trends and correlation of antibacterial usage and bacterial resistance: time series analysis for antibacterial stewardship in a Chinese teaching hospital (2009-2013)

The Novel "RISC" Score as a Risk-prediction Model of Carbapenem-resistant Hospital-acquired Infections in Adult Sepsis Patients - A Prospective Observational Study

Aim and background

Antimicrobial sensitivity (AMS) reports are often available after 72 hours of identification of gram-negative (GN) hospital-acquired infection (HAI). Prediction of carbapenem-resistant infection (CRI) among GN strains is important even before AMS reports are available, for judicious use of empirical antibiotics. We aimed to study the predictors of CRI in patients with HAI.

Materials and methods

We conducted a single-center prospective observational study between April 2023 and September 2024 on patients of GN sepsis with HAI. The use of empirical carbapenem antibiotics, organ dysfunction scores, the modified nutritional risk in critically ill (mNUTRIC) score, blood-count-derived inflammation indices, type of HAI, AMS reports, and in-hospital mortality were noted.

Results

A total of 935 sepsis patients with HAI were screened, and there were 195 patients with GN infection. Among the 195 patients, 145 (74.4%) had CRI and 50 (25.6%) had non-CRI. Multivariable logistic regression revealed that the length of intensive care unit (ICU) stay before the day of HAI (p = 0.009, adjusted odds ratio (OR) 1.155, 95% confidence interval (CI) 1.037-1.286), presence of ventilator-associated pneumonia (VAP) (p-value < 0.001, adjusted OR 4.170, 95% CI: 1.858-9.361), empirical carbapenem antibiotics before the day of HAI (p-value = 0.004, adjusted OR 3.164, 95% CI: 1.439-6.957), and septic shock on the day of HAI (p-value 0.012, adjusted OR 4.162, 95% CI: 1.366-12.677) were the independent risk factors of CRI.

Conclusion

In GN sepsis patients with HAI, respiratory infection (VAP), length of ICU stay prior to HAI, septic shock, and empirical carbapenem antibiotic administration are risk factors of CRI.

How to cite this article

Mareguddi AB, Chaudhuri S, Shanmukhappa SM, Parampalli V, Bhatt MT, Fernandes R, et al. The Novel "RISC" Score as a Risk-prediction Model of Carbapenem-resistant Hospital-acquired Infections in Adult Sepsis Patients - A Prospective Observational Study. Indian J Crit Care Med 2025;29(4):352-362.

Carbapenem Usage in the Initial Antibiotic Therapy of Sepsis in Japanese Intensive Care Units

Background Achieving a balance between the utilization and limitation of carbapenems for initial sepsis therapy is imperative, yet documentation on the use of carbapenems in sepsis treatment is limited. This study aimed to ascertain the prevalence of carbapenem use in Japanese intensive care units (ICUs) and evaluate the association between its use in the initial antibiotic therapy for sepsis and patient prognosis.  Methods This study is a post hoc descriptive analysis of the Focused Outcome Research on Emergency Care for Acute Respiratory Distress Syndrome, Sepsis, and Trauma (FORECAST), a multicenter, prospective cohort study conducted in 59 ICUs in Japan from January 2016 to March 2017. This study described the rate of carbapenem use overall and in each ICU and assessed the association between carbapenem use and in-hospital mortality by generalized linear mixed effect model adjusting for patient characteristics as fixed effect confounders and the hospitals as random effect confounders. Results Out of 1140 participants, 627(55.0%) received and 513 (45.0%) did not receive carbapenems following the diagnosis of severe sepsis or septic shock. Patient severity was similar in both groups in terms of Sepsis-related Organ Failure Assessment (SOFA; 9 and 8) and Acute Physiology and Chronic Health Evaluation II (APACHE II; 23 and 22) scores. Among 48 of the 59 ICUs that registered more than three patients in the FORECAST registry, the median carbapenem utilization rate stood at 55.2% (minimum: 20.0%, maximum: 100.0%, IQR: 43.6%-67.2%). Hospital mortality rates were 25.6% and 20.5% in carbapenem recipients and non-recipients, respectively. A correlation between initial carbapenem use and increased in-hospital mortality was discerned in the unadjusted model (difference of 5.2%), but this association was not evident in the adjusted model (difference of 1.2%; 95%CI: -4.3,6.6; p=0.66). Conclusions Initial antibiotic therapy with carbapenems was noted in over half of the sepsis patients in Japanese ICUs. In-hospital mortality was not associated with the use of carbapenems.

Effects of pay-for-performance based antimicrobial stewardship on antimicrobial consumption and expenditure: An interrupted time series analysis

Objectives

To evaluate the impact of pay-for-performance on antimicrobial consumption and antimicrobial expenditure in a large teaching hospital in Guangzhou, China.

Methods

We collected data from hospital information system from January 2018 through September 2022 in the inpatient wards. Antimicrobial consumption was evaluated using antibiotic use density (AUD) and antibiotic use rate (AUR). The economic impact of intervention was assessed by antimicrobial expenditure percentage. The data was analyzed using interrupted time series (ITS) analysis.

Results

Following the implementation of the intervention, immediate decreases in the level of AUD were observed in Department of Hematology Unit 3 (β = -66.93 DDDs/100PD, P = 0.002), Urology (β = -32.80 DDDs/100PD, P < 0.001), Gastrointestinal Surgery Unit 3 (β = -11.44 DDDs/100PD, P = 0.03), Cardiac Surgery (β = -14.30 DDDs/100PD, P = 0.01), ICU, Unit 2 (β = -81.91 DDDs/100PD, P = 0.02) and Cardiothoracic Surgery ICU (β = -41.52 DDDs/100PD, P = 0.05). Long-term downward trends in AUD were also identified in Organ Transplant Unit (β = -1.64 DDDs/100PD, P = 0.02). However, only Urology (β = -6.56 DDDs/100PD, P = 0.02) and Gastrointestinal Surgery Unit 3 (β = -8.50 %, P = 0.01) showed an immediate decrease in AUR, and long-term downward trends in AUR were observed in Pediatric ICU (β = -1.88 %, P = 0.05) and ICU Unit 1 (β = -0.55 %, P = 0.02).

Conclusion

This study demonstrates that the adoption of pay-for-performance effectively reduces antibiotic consumption in specific departments of a hospital in Guangzhou in the short term. However, it is important to recognize that the long-term impact of such interventions is often limited. Additionally, it should be noted that the overall effectiveness of the intervention across the entire hospital was not significant.

Exploring the Impact of In Basket Metrics on the Adoption of a New Electronic Health Record System Among Specialists in a Tertiary Hospital in Alberta: Descriptive Study

BACKGROUND

Health care organizations implement electronic health record (EHR) systems with the expectation of improved patient care and enhanced provider performance. However, while these technologies hold the potential to create improved care and system efficiencies, they can also lead to unintended negative consequences, such as patient safety issues, communication problems, and provider burnout.

OBJECTIVE

This study aims to document metrics related to the In Basket communication hub (time in In Basket per day, time in In Basket per appointment, In Basket messages received per day, and turnaround time) of the EHR system implemented by Alberta Health Services, the province-wide health delivery system called Connect Care (Epic Systems). The objective was to identify how a newly implemented EHR system was used, the timing of its use, and the duration of use specifically related to In Basket activities.

METHODS

A descriptive study was conducted. Due to the diversity of specialties, the providers were grouped into medical and surgical based on previous similar studies. The participants were further subgrouped based on their self-reported clinical full-time equivalent (FTE ) measure. This resulted in 3 subgroups for analysis: medical FTE <0.5, medical FTE >0.5, and surgical (all of whom reported FTE >0.5). The analysis was limited to outpatient clinical interactions and explicitly excluded inpatient activities.

RESULTS

A total of 72 participants from 19 different specialties enrolled in this study. The providers had, on average, 8.31 appointments per day during the reporting periods. The providers received, on average, 21.93 messages per day, and they spent 7.61 minutes on average in the time in In Basket per day metric and 1.84 minutes on average in the time in In Basket per appointment metric. The time for the providers to mark messages as done (turnaround time) was on average 11.45 days during the reporting period. Although the surgical group had, on average, approximately twice as many appointments per scheduled day, they spent considerably less connected time (based on almost all time metrics) than the medical group. However, the surgical group took much longer than the medical group to mark messages as done (turnaround time).

CONCLUSIONS

We observed a range of patterns with no consistent direction. There does not seem to be evidence of a "learning curve," which would have shown a consistent reduction in time spent on the system over time due to familiarity and experience. While this study does not show how the included metrics could be used as predictors of providers' satisfaction or feelings of burnout, the use trends could be used to start discussions about future Canadian studies needed in this area.

Impact of reduced antibiotic treatment duration on antimicrobial resistance in critically ill patients in the randomized controlled SAPS-trial

Background

In the previously reported SAPS trial (https://clinicaltrials.gov/ct2/show/NCT01139489), procalcitonin-guidance safely reduced the duration of antibiotic treatment in critically ill patients. We assessed the impact of shorter antibiotic treatment on antimicrobial resistance development in SAPS patients.

Materials and methods

Cultures were assessed for the presence of multi-drug resistant (MDR) or highly resistant organisms (HRMO) and compared between PCT-guided and control patients. Baseline isolates from 30 days before to 5 days after randomization were compared with those from 5 to 30 days post-randomization. The primary endpoint was the incidence of new MDR/HRMO positive patients.

Results

In total, 8,113 cultures with 96,515 antibiotic test results were evaluated for 439 and 482 patients randomized to the PCT and control groups, respectively. Disease severity at admission was similar for both groups. Median (IQR) durations of the first course of antibiotics were 6 days (4-10) and 7 days (5-11), respectively (p = 0.0001). Antibiotic-free days were 7 days (IQR 0-14) and 6 days (0-13; p = 0.05). Of all isolates assessed, 13% were MDR/HRMO positive and at baseline 186 (20%) patients were MDR/HMRO-positive. The incidence of new MDR/HRMO was 39 (8.9%) and 45 (9.3%) in PCT and control patients, respectively (p = 0.82). The time courses for MDR/HRMO development were also similar for both groups (p = 0.33).

Conclusions

In the 921 randomized patients studied, the small but statistically significant reduction in antibiotic treatment in the PCT-group did not translate into a detectable change in antimicrobial resistance. Studies with larger differences in antibiotic treatment duration, larger study populations or populations with higher MDR/HRMO incidences might detect such differences.

Development and validation of nomograms for predicting the risk probability of carbapenem resistance and 28-day all-cause mortality in gram-negative bacteremia among patients with hematological diseases

Objectives

Gram-negative bacteria (GNB) bloodstream infections (BSIs) are the most widespread and serious complications in hospitalized patients with hematological diseases. The emergence and prevalence of carbapenem-resistant (CR) pathogens has developed into a considerable challenge in clinical practice. Currently, nomograms have been extensively applied in the field of medicine to facilitate clinical diagnosis and treatment. The purpose of this study was to explore risk indicators predicting mortality and carbapenem resistance in hematological (HM) patients with GNB BSI and to construct two nomograms to achieve personalized prediction.

Methods

A single-center retrospective case-control study enrolled 244 hospitalized HM patients with GNB-BSI from January 2015 to December 2019. The least absolute shrinkage and selection operator (LASSO) regression analysis and multivariate logistic regression analysis were conducted to select potential characteristic predictors of plotting nomograms. Subsequently, to evaluate the prediction performance of the models, the prediction models were internally validated using the bootstrap approach (resampling = 1000) and 10-fold cross validation.

Results

Of all 244 eligible patients with BSI attributed to GNB in this study, 77 (31.6%) were resistant to carbapenems. The rate of carbapenem resistance exhibited a growing tendency year by year, from 20.4% in 2015 to 42.6% in 2019 (p = 0.004). The carbapenem resistance nomogram constructed with the parameters of hypoproteinemia, duration of neutropenia ≥ 6 days, previous exposure to carbapenems, and previous exposure to cephalosporin/β-lactamase inhibitors indicated a favorable discrimination ability with a modified concordance index (C-index) of 0.788 and 0.781 in both the bootstrapping and 10-fold cross validation procedures. The 28-day all-cause mortality was 28.3% (68/240). The prognosis nomogram plotted with the variables of hypoproteinemia, septic shock, isolation of CR-GNB, and the incomplete remission status of underlying diseases showed a superior discriminative ability of poorer clinical prognosis. The modified C-index of the prognosis nomogram was 0.873 with bootstrapping and 0.887 with 10-fold cross validation. The decision curve analysis (DCA) for two nomogram models both demonstrated better clinical practicality.

Conclusions

For clinicians, nomogram models were effective individualized risk prediction tools to facilitate the early identification of HM patients with GNB BSI at high risk of mortality and carbapenem resistance.

Trends and Correlation Between Antimicrobial Resistance and Antibiotics Consumption in a Specialist Children’s Hospital from 2016 to 2021

Purpose

To explore the trends and correlation between antibiotics consumption and antimicrobial resistance in children in a specialist hospital from 2016–2021 in China.

Patients and Methods

This retrospective study investigated data on the consumption of antibiotics and antimicrobial resistance in children. Antibiotics consumption was expressed as defined daily doses (DDDs)/1000 patient-days based on the Guidelines for Anatomical Therapeutic Chemical. The trends in antibiotics consumption and antimicrobial resistance rates were analyzed by linear regression, while Spearman correlation analysis was employed to evaluate their correlations.

Results

An increasing trend in the annual consumption of carbapenems and monobactams was detected (all P<0.05). A significant upward trend was detected in the annual resistance rates of Enterococcus faecium to ciprofloxacin, Streptococcus pneumonia to ceftriaxone, Acinetobacter baumannii to carbapenems, Enterobacter cloacae to carbapenems, Pseudomonas aeruginosa to ceftazidime, and Escherichia coli to cefepime, while the annual resistance rates of Escherichia coli to carbapenems had a significant downward trend (all P<0.05). The consumption of cephalosporin/β-lactamase inhibitor (C/BLI) combinations and carbapenems had significant positive correlations with the resistance rates of Acinetobacter baumannii to carbapenems (r=0.763, P<0.001; r=0.806, P<0.001), Enterobacter cloacae to carbapenems (r=0.675, P<0.001; r=0.417, P=0.043), and Pseudomonas aeruginosa to ceftazidime (r=0.625, P=0.001; r=0.753, P<0.001), respectively. Also, increasing consumption of monobactams was related to the upward resistance rates of Acinetobacter baumannii to carbapenems (r=0.557, P=0.005) and Enterobacter cloacae to carbapenems (r=0.507, P= 0.011).

Conclusion

This study demonstrated significant positive associations between antibiotics consumption and specific antimicrobial resistance rates. The current findings pointed out some directions to pursue in controlling the prevalence of certain resistant bacterial strains in children.

Identifying key influences on antibiotic use in China: a systematic scoping review and narrative synthesis

INTRODUCTION

The inappropriate use of antibiotics is a key driver of antimicrobial resistance. In China, antibiotic prescribing and consumption exceed recommended levels and are relatively high internationally. Understanding the influences on antibiotic use is essential to informing effective evidence-based interventions. We conducted a scoping review to obtain an overview of empirical research about key behavioural, cultural, economic and social influences on antibiotic use in China.

METHODS

Searches were conducted in Econlit, Medline, PsycINFO, Social Science citation index and the Cochrane Database of Systematic Reviews for the period 2003 to early 2018. All study types were eligible including observational and intervention, qualitative and quantitative designs based in community and clinical settings. Two authors independently screened studies for inclusion. A data extraction form was developed incorporating details on study design, behaviour related to antibiotic use, influences on behaviour and information on effect (intervention studies only).

RESULTS

Intervention studies increased markedly from 2014, and largely focused on the impact of national policy and practice directives on antibiotic use in secondary and tertiary healthcare contexts in China. Most studies used pragmatic designs, such as before and after comparisons. Influences on antibiotic use clustered under four themes: antibiotic prescribing; adherence to antibiotics; self-medicating behaviour and over-the-counter sale of antibiotics. Many studies highlighted the use of antibiotics without a prescription for common infections, which was facilitated by availability of left-over medicines and procurement from local pharmacies.

CONCLUSIONS

Interventions aimed at modifying antibiotic prescribing behaviour show evidence of positive impact, but further research using more robust research designs, such as randomised trials, and incorporating process evaluations is required to better assess outcomes. The effect of national policy at the primary healthcare level needs to be evaluated and further exploration of the influences on antibiotic self-medicating is required to develop interventions that tackle this behaviour.

Trends, relationships and case attribution of antibiotic resistance between children and environmental sources in rural India

Bacterial antibiotic resistance is an important global health threat and the interfaces of antibiotic resistance between humans, animals and the environment are complex. We aimed to determine the associations and overtime trends of antibiotic resistance between humans, animals and water sources from the same area and time and estimate attribution of the other sources to cases of human antibiotic resistance. A total of 125 children (aged 1-3 years old) had stool samples analysed for antibiotic-resistant bacteria at seven time points over two years, with simultaneous collection of samples of animal stools and water sources in a rural Indian community. Newey-West regression models were used to calculate temporal associations, the source with the most statistically significant relationships was household drinking water. This is supported by use of SourceR attribution modelling, that estimated the mean attribution of cases of antibiotic resistance in the children from animals, household drinking water and wastewater, at each time point and location, to be 12.6% (95% CI 4.4-20.9%), 12.1% (CI 3.4-20.7%) and 10.3% (CI 3.2-17.3%) respectively. This underlines the importance of the 'one health' concept and requires further research. Also, most of the significant trends over time were negative, suggesting a possible generalised improvement locally.

Trends of Antibiotic Use and Expenditure After an Intensified Antimicrobial Stewardship Policy at a 2,200-Bed Teaching Hospital in China

Objective: This study aimed to evaluate the effects of intensified Chinese special rectification activity on clinical antibiotic use (CSRA) policy on a tertiary-care teaching hospital. Methods: A 48-month longitudinal dataset involving inpatients, outpatients, and emergency patients were collected. Study period included pre-intervention stage (adopting soft measures like systemic training) and post-intervention stage (applying antibiotic control system to intensify CSRA policy). Antibiotic use was evaluated by antibiotic use rate (AUR) or antibiotic use density (AUD). Economic indicator was evaluated by antibiotic cost in prescription or antibiotic expenditure in hospitalization. Data was analyzed by interrupted time series (ITS) analysis. Results: The medical quality indicators remained stable or improved during the study period. AUR of inpatients (AURI) declined 0.553% per month (P = 0.025) before the intervention and declined 0.354% per month (P = 0.471) after the intensified CSRA policy was implemented. AUD, expressed as defined daily doses per 100 patients per day (DDDs/100PD), decreased by 1.102 DDDs/100PD per month (P = 0.021) before and decreased by 0.597 DDDs/100PD per month (P = 0.323) thereafter. The ratio of antibiotic expenditure to medication expenditure (AE/ME) decreased by 0.510% per month (P = 0.000) before and fell by 0.096% (P = 0.000) per month thereafter. AE per patient decreased by 25.309 yuan per month (P = 0.002) before and decreased by 7.987 yuan per month (P = 0.053) thereafter. AUR of outpatient (AURO) decreased by 0.065% per month before (P = 0.550) and decreased by 0.066% per month (P = 0.994) thereafter. The ratio of antibiotic cost to prescription cost in outpatient (ACO/PCO) decreased by 0.182% per month (P = 0.506) before and decreased by 0.216% per month (P = 0.906) thereafter. AUR of emergency patient (AURE) decreased by 0.400% per month (P = 0.044) before and decreased by 0.092% per month (P = 0.164) thereafter. The ratio of antibiotic cost to prescription cost in emergency patient (ACE/PCE) decreased by 0.616% per month (P < 0.001) before and decreased by 0.151% per month (P < 0.001) thereafter. Conclusions: Implementation of CSRA policy was associated with declining antibiotic use and antibiotic expenditure in inpatients, outpatients, and emergency patients. However, it is also important to note that the declining trend of antibiotic consumption slowed due to the limited capacity for decline in the later stages of CSRA intervention.

Microbiome-pathogen interactions drive epidemiological dynamics of antibiotic resistance: A modeling study applied to nosocomial pathogen control

The human microbiome can protect against colonization with pathogenic antibiotic-resistant bacteria (ARB), but its impacts on the spread of antibiotic resistance are poorly understood. We propose a mathematical modeling framework for ARB epidemiology formalizing within-host ARB-microbiome competition, and impacts of antibiotic consumption on microbiome function. Applied to the healthcare setting, we demonstrate a trade-off whereby antibiotics simultaneously clear bacterial pathogens and increase host susceptibility to their colonization, and compare this framework with a traditional strain-based approach. At the population level, microbiome interactions drive ARB incidence, but not resistance rates, reflecting distinct epidemiological relevance of different forces of competition. Simulating a range of public health interventions (contact precautions, antibiotic stewardship, microbiome recovery therapy) and pathogens (Clostridioides difficile, methicillin-resistant Staphylococcus aureus, multidrug-resistant Enterobacteriaceae) highlights how species-specific within-host ecological interactions drive intervention efficacy. We find limited impact of contact precautions for Enterobacteriaceae prevention, and a promising role for microbiome-targeted interventions to limit ARB spread.

Effects of Regulation on Carbapenem Prescription in a Large Teaching Hospital in China: An Interrupted Time Series Analysis, 2016-2018

Purpose

Carbapenem resistance due to the overuse of carbapenems has become a public health problem worldwide, particularly in low- and middle-income countries (LMICs). However, there are few policies guiding carbapenem prescription, and their effectiveness is still unclear. A regulation targeting carbapenem prescription was implemented in March 2017 in China. This study aimed to assess the effects of the regulation for providing evidence on the prudent use of carbapenems.

Patients and Methods

This was an interventional, retrospective study started in January 2017. The intervention covered establishing performance appraisal indicators, special authorisation, strict prescribing restrictions, and dedicated supervision, particularly in the intensive care unit (ICU). Data on adult inpatients who received at least one carbapenems were extracted from January 2016 to December 2018. Segmented regression analysis was performed to evaluate the effect of the regulation.

Results

A total of 2005 inpatients received carbapenems. Segmented regression models showed an immediate decline in the intensity of antibiotic consumption (IAC) of carbapenems (coefficient = −9.65, p < 0.001), particularly imipenem (coefficient = −6.82, p = 0.002), and the antibiotic consumption of carbapenems (coefficient = −133.60, p = 0.003) in the ICU. And there is a decreasing trend in the IAC of meropenem (coefficient = −0.03, p = 0.008) in all departments. Furthermore, the IAC of carbapenems and imipenem (coefficient = −0.36, p = 0.035; coefficient = −0.49, p = 0.025, respectively), and the average length of stay (ALoS) (coefficient = −0.73, p < 0.001) showed downward trends in the ICU.

Conclusion

The intervention effectively reduced the IAC of carbapenems and imipenem, carbapenem consumption and the ALoS in the ICU, and the IAC of meropenem in all departments. The effects of the intervention were significant in the ICU, which indicated an urgent need for stronger regulations focusing on critical departments in the future.

Do specific antimicrobial stewardship interventions have an impact on carbapenem resistance in Gram-negative bacilli? A multicentre quasi-experimental ecological study: time-trend analysis and characterization of carbapenemases

BACKGROUND

Carbapenem-resistant Gram-negative bacilli (CR-GNB) are among the most threatening microorganisms worldwide and carbapenem use facilitates their spread. Antimicrobial stewardship programmes (ASPs) can help to optimize the use of antibiotics. This study evaluates the impact of a multifaceted educational ASP on carbapenem use and on the epidemiology of CR-GNB.

METHODS

We conducted a quasi-experimental, time-series study in seven hospitals, from January 2014 to September 2018. The key intervention was composed of educational interviews promoting the appropriate use of carbapenems. The primary endpoints were carbapenem consumption and incidence density (ID) of CR-GNB. All non-duplicated CR-GNB clinical isolates were tested using phenotypic assays and PCR for the presence of carbapenemases. Joinpoint regression and interrupted time-series analyses were used to determine trends.

RESULTS

A decrease in carbapenem consumption throughout the study period [average quarterly percentage change (AQPC) -1.5%, P < 0.001] and a -8.170 (-16.064 to -0.277) level change following the intervention were observed. The ID of CR-Acinetobacter baumannii decreased (AQPC -3.5%, P = 0.02) and the overall ID of CR-GNB remained stable (AQPC -0.4%, P = 0.52). CR-GNB, CR-Pseudomonas aeruginosa and CR-A. baumannii IDs per hospital correlated with the local consumption of carbapenems. The most prevalent carbapenem resistance mechanisms were OXA-23 for CR-A. baumannii (76.1%), OXA-48 for CR-Klebsiella pneumoniae (66%) and no carbapenemases for CR-P. aeruginosa (91.7%). The epidemiology of carbapenemases was heterogeneous throughout the study, especially for carbapenemase-producing Enterobacteriaceae.

CONCLUSIONS

In conclusion, a multifaceted, educational interview-based ASP targeting carbapenem prescribing reduced carbapenem use and the ID of CR-A. baumannii.

Trends and correlation between antibacterial consumption and carbapenem resistance in gram-negative bacteria in a tertiary hospital in China from 2012 to 2019

Background

To investigate the trends and correlation between antibacterial consumption and carbapenem resistance in Gram-negative bacteria from 2012 to 2019 in a tertiary-care teaching hospital in southern China.

Methods

This retrospective study included data from hospital-wide inpatients collected between January 2012 and December 2019. Data on antibacterial consumption were expressed as defined daily doses (DDDs)/1000 patient-days. Antibacterials were classified according to the Anatomical Therapeutic Chemical (ATC) classification system. The trends in antimicrobial usage and resistance were analyzed by linear regression, while Pearson correlation analysis was used for assessing correlations.

Results

An increasing trend in the annual consumption of tetracyclines, β-lactam/β-lactamase inhibitor (BL/BLI) combinations, and carbapenems was observed (P < 0.05). Carbapenem resistance in Acinetobacter baumannii (A. baumannii) significantly increased (P < 0.05) from 18% in 2012 to 60% in 2019. Moreover, significant positive correlations were found between resistance to carbapenems in A. baumannii (P < 0.05) and Escherichia coli (E. coli; P < 0.05) and consumption of carbapenems, while the resistance rate of A. baumannii to carbapenems was positively correlated with cephalosporin/β-lactamase inhibitor (C/BLI) combinations (P < 0.01) and tetracyclines usage (P < 0.05). We also found that use of quinolones was positively correlated with the resistance rate of Burkholderia cepacia (B. cepacia) to carbapenems (P < 0.05), and increasing uses of carbapenems (P < 0.01) and penicillin/β-Lactamase inhibitor (P/BLI) combinations (P < 0.01) were significantly correlated with reduced resistance of Enterobacter cloacae (E. cloacae) to carbapenems.

Conclusion

These results revealed significant correlations between consumption of antibiotics and carbapenem resistance rates in Gram-negative bacteria. Implementing proper management strategies and reducing the unreasonable use of antibacterial drugs may be an effective measure to reduce the spread of carbapenem-resistant Gram-negative bacteria (CRGN), which should be confirmed by further studies.

Impact of cascade reporting of antimicrobial susceptibility on fluoroquinolone and meropenem consumption at a Veterans' Affairs medical center

OBJECTIVE

To determine whether cascade reporting is associated with a change in meropenem and fluoroquinolone consumption.

DESIGN

A quasi-experimental study was conducted using an interrupted time series to compare antimicrobial consumption before and after the implementation of cascade reporting.

SETTING

A 399-bed, tertiary-care, Veterans' Affairs medical center.

PARTICIPANTS

Antimicrobial consumption data across 8 inpatient units were extracted from the Center for Disease Control and Prevention (CDC) National Health Safety Network (NHSN) antimicrobial use (AU) module from April 2017 through March 2019, reported as antimicrobial days of therapy (DOT) per 1,000 days present (DP).

INTERVENTION

Cascade reporting is a strategy of reporting antimicrobial susceptibility test results in which secondary agents are only reported if an organism is resistant to primary, narrow-spectrum agents. A multidisciplinary team developed cascade reporting algorithms for gram-negative bacteria based on local antibiogram and infectious diseases practice guidelines, aimed at restricting the use of fluoroquinolones and carbapenems. The algorithms were implemented in March 2018.

RESULTS

Following the implementation of cascade reporting, mean monthly meropenem (P =.005) and piperacillin/tazobactam (P = .002) consumption decreased and cefepime consumption increased (P < .001). Ciprofloxacin consumption decreased by 2.16 DOT per 1,000 DP per month (SE, 0.25; P < .001). Clostridioides difficile rates did not significantly change.

CONCLUSION

Ciprofloxacin consumption significantly decreased after the implementation of cascade reporting. Mean meropenem consumption decreased after cascade reporting was implemented, but we observed no significant change in the slope of consumption. cascade reporting may be a useful strategy to optimize antimicrobial prescribing.

Association of Antibiotic Use with the Resistance Epidemiology of Pseudomonas aeruginosa in a Hospital Setting: A Four-Year Retrospective Time Series Analysis

Background: Even though, Pseudomonas aeruginosa is a common cause of hospital-acquired infections, treatment is challenging because of decreasing rates of susceptibility to many broad-spectrum antibiotics. Methods: Consumption data of eight broad spectrum antimicrobial agents and resistance rates of P. aeruginosa were collected for 48 consecutive months. Autoregressive integrated moving average (ARIMA) and transfer functions models were used to develop relationships between antibiotic use and resistance. Results: Positive correlations between P. aeruginosa resistance and uses of ciprofloxacin (p < 0.001), meropenem (p < 0.001), and cefepime (p = 0.005) were identified. Transfer function models showed the quantified effect of each of these antibiotics on resistance. Regarding levofloxacin, ceftazidime, piperacillin/tazobactam and imipenem, no significant relationships were found. For ceftazidime and levofloxacin, this was probably due to their low consumption, while for imipenem the reason can possibly be ascribed to the already high established P. aeruginosa resistance in the hospital. Conclusion: In the hospital setting, the effect of antimicrobial agents’ consumption on the susceptibility epidemiology of P. aeruginosa differs significantly for each one of them. In this study, the role of precedent use of meropenem, cefepime and ciprofloxacin was quantified in the development of P. aeruginosa resistance.

Impact of antibiotic prescription on the resistance of Klebsiella pneumoniae at a tertiary hospital in China, 2012-2019

BACKGROUND

The incidence of Klebsiella pneumoniae (KP) infections is worrisome. Previous studies have shown that increased antibiotic treatment might affect the resistance profile of this organism. The objective of this study was to describe the resistance profile of KP strains and to correlate it with antibiotics consumption.

METHODS

A retrospective observational analysis was performed to examine exposure to antibiotics and resistant profile, comparing the results of different measuring outcomes of resistance (the incidence and the percentage of resistant KP) during January 2012 to June 2019 by using the autoregressive integrated moving average and transfer function model.

RESULTS

During the study period, the use of some third-generation cephalosporins and carbapenems continued to increase and a total of 5,519 KP isolates were collected. There were positive relationships between amikacin-resistant KP, ciprofloxacin-resistant KP, and corresponding antibiotic use in the transfer function models; both for the incidence rate and the resistant rate (time lag = 0) (P < .05).

CONCLUSIONS

The present study confirms that the history of amikacin or ciprofloxacin use influences the susceptibility of these agents against KP with no delay. Similar results were obtained with different measuring outcomes of resistance.

Impact of a pharmacist-driven antimicrobial stewardship program in a private hospital in Costa Rica

Objective.

To measure the impact generated by the implementation of the pharmacy-driven antimicrobial stewardship program of the Clínica Bíblica Hospital.

Methods.

This is a retrospective observational study that evaluates the consumption of antibiotics for the periods before and during implementation of the Clínica Bíblica Hospital antimicrobial stewardship program, calculated by means of defined daily dose per 1 000 patient-days and days of therapy per 1 000 patient-days. In addition, bacterial resistance patterns for the periods 2014–2015 and 2016–2017 were compared.

Results.

Consumption of most-used antibiotics was calculated, looking for trends that might be associated with the activities implemented by the Clínica Bíblica Hospital antimicrobial stewardship program. Comparing some of the antibiotics with the highest consumption in periods I and II, use of levofloxacin and ceftriaxone showed a decrease of 54.0% (p < 0.001) and 14.6% (p = 0.003), respectively, whereas there was an increase in the use of cefazolin of 4 539.3% (p < 0.001). Regarding percentage of bacterial resistance, in most bacterial isolates no statistically significant changes were observed between the two periods.

Conclusions.

A reduction in the overall consumption of antibiotics has been achieved over time, most likely attributable to the antimicrobial stewardship program. However, this trend was not observed for all the antibiotics studied. The pattern of resistance among the commonly isolated microorganisms did not vary greatly between the periods studied, which suggests that either the antimicrobial stewardship program may have prevented an increase in bacterial resistance since its implementation, or that it is too soon to see impact on bacterial resistance.

Long-Term Surveillance of Antibiotic Prescriptions and the Prevalence of Antimicrobial Resistance in Non-Fermenting Gram-Negative Bacilli

The increasing emergence of multidrug-resistant (MDR) bacteria has been recognized as a public health threat worldwide. Hospitalized patients and outpatients are commonly infected by non-fermenting Gram-negative bacilli (NFGNB), particularly the Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ACB) and Pseudomonas aeruginosa. Antimicrobial agents are critical for treating the nosocomial infections caused by NFGNB. The aim of this study was to assess antimicrobial resistance and the use of antimicrobial agents. The bacterial isolates of 638,152 specimens from both inpatients and outpatients, retrieved from 2001 to 2008 at a medical center in central Taiwan, were examined for their susceptibility to various antimicrobial agents, including cefepime, imipenem, ciprofloxacin, gentamicin, amikacin, meropenem, and levofloxacin. Administrated prescriptions of the monitored antibiotics were analyzed using the Taiwan National Health Insurance Research Database (NHIRD). Our results show that the defined daily doses (DDDs) for cefepime, imipenem, and ciprofloxacin increased with time, and a trend toward reduced antimicrobial sensitivities of both ACB and P. aeruginosa was noticeable. In conclusion, the antimicrobial sensitivities of ACB and P. aeruginosa were reduced with the increased use of antibiotics. Continuous surveillance of antibiotic prescriptions and the prevalence of emerging resistance in nosocomial infections is warranted.

Variation in a novel antipseudomonal antimicrobial consumption metric across hospital inpatient units at a Veterans Affairs hospital: A retrospective cohort study

A novel antimicrobial consumption metric designed to identify the proportion of carbapenem consumption (PoCC) among broad-spectrum antipseudomonal antimicrobials has been shown to vary significantly by US Census Bureau region. This retrospective surveillance study identified significant total PoCC variability (27%; P = .001) across 8 inpatient units from January 2017 through June 2018. This metric may be useful in identifying and comparing inpatient units that may be overusing antipseudomonal carbapenems.

Antimicrobial resistance surveillance and prediction of Gram-negative bacteria based on antimicrobial consumption in a hospital setting: A 15-year retrospective study

Antimicrobial resistance, a major threat to human health, is mainly driven by the overuse of antimicrobials. The purpose of this study was to further investigate the relationship between antimicrobial use and resistance with a 15-year record in Southwest hospital, one of the largest hospitals in Southwest China and a university affiliated hospital, thus to further predict the antimicrobial resistance in an autoregressive integrated moving average (ARIMA) manner. Kirby-Bauer tests were carried out to figure out the drug sensitivity of Gram-negative bacterial. Antimicrobials (β-lactamase inhibitor complex, aminoglycosides, quinolones, third and fourth-generation cephalosporins, carbapenems, cephamycins, oxacephems, and sulfonamides) consumption were calculated according to World Health Organization (WHO) anatomical therapeutic chemical classification index and expressed as annual defined daily dose (DDD) or DDD per 1000 out patients. Resistance rates of levofloxacin-resistant Escherichia coli, ceftazidime-resistant Klebsiella pneumoniae, amikacin-resistant Bacterium levans, imipenem-resistant Pseudomonas aeruginosa is positively correlated with the usage of aminoglycosides and quinolones; resistance rates of imipenem-resistant Acinetobacter baumanii is positively correlated with the usage of carbapenemes (P-value between the drug resistance of levofloxacin-resistant E. coli, ceftazidime-resistant K. pneumoniae and the usage of aminoglycosides is under .05, the other P-value are under .01); resistance rates of the drug resistance of levofloxacin-resistant E. coli is positively correlated with the usage of oxacephems (P < .01); resistance rates of imipenem-resistant P. aeruginosa is positively correlated with the usage of oxacephems and sulfonamides (P < .01).The present study presents one of the largest and longest retrospective analyses in China between antimicrobial consumption and antimicrobial resistance. Change of the usage of several antibacterial drugs has great influence on the drug resistance of Gram-negative bacterial. Of particular, ARIMA forecasting revealed that carbapenem related bacterial resistance should be closely watched.

Time series analysis of antibacterial usage and bacterial resistance in China: observations from a tertiary hospital from 2014 to 2018

PURPOSE

To describe trends and correlation between antibacterial exposure and bacterial resistance from hospitalized patients in a hospital in southern China.

PATIENTS AND METHODS

This study used hospital-wide data regarding antimicrobial resistance and consumption between January 1, 2014 and December 31, 2018. Antibacterial consumption was expressed as antimicrobial use density (AUD). The changes in trends and associations between antibacterial utilization and resistance were analyzed using linear regression and time series analysis.

RESULTS

The total AUD of all antimicrobials decreased year by year (50.66 in 2014 vs 44.28 in 2018, P=0.03). The annual use of antimicrobials, such as penicillins, monobactams, aminoglycosides, macrolides, and lincosamides, significantly decreased (P<0.05), while the annual use of quinolones and tetracyclines significantly increased (P<0.05). Among the top ten isolated bacteria, antimicrobial resistance trends of Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Staphylococcus aureus, and Staphylococcus epidermidis significantly decreased (P<0.05). Significant positive correlation was found between AUD of carbapenems and resistance rate of Acinetobacter baumannii to imipenem (β=32.87, P<0.01), as well as the correlation between AUD of quinolones and resistance rate of Enterococcus faecium to levofloxacin (β=104.40, P<0.01).

CONCLUSION

The consumption of antibiotics and antibiotic resistance has been significantly improved in this tertiary hospital. Additionally, the efforts of China's antibiotic management may be suggested by the relationship between indicated antibiotic resistance and consumption. However, overall AUD levels and poor control of the use of antibiotics, such as quinolones and tetracyclines, still require strengthened management.

Trends and correlation of antibiotic susceptibility and antibiotic consumption at a large teaching hospital in China (2007-2016): a surveillance study

PURPOSE

To evaluate the trends and correlation between the antibiotic consumption and susceptibility of eight most frequent isolates in the First Affiliated Hospital of Zhejiang University (2007-2016).

METHOD

This study was based on the yearly surveillance data in a 2500-bed capacity tertiary-care teaching hospital. Trends and correlation were, respectively, analyzed by linear regression and Pearson's correlation coefficient.

RESULTS

The consumption of all antibiotics decreased by 10.8% over time, especially first-generation cephalosporins (p=0.001), fourth-generation cephalosporins (p=0.01), aminoglycosides (p<0.001), and fluoroquinolones (p<0.001), but increased remarkably in linezolid, carbapenems, glycopeptides, and third-generation cephalosporins (3GCs). 72.7% of trend analyses indicated increased susceptibility to antibiotics with remarkably decreased consumption. In particular, susceptibility to aminoglycosides and fluoroquinolones remarkably increased in seven of eight pathogens and negatively correlated with the corresponding antibiotic consumption (p<0.05). Isolation density significantly declined in methicillin-resistant Staphylococcus aureus (54.9-41.3%, p=0.009) and in extended-spectrum β-lactamase producing Klebsiella pneumoniae (42.4-15.6%, p=0.007), which positively correlated with the consumption of fluoroquinolones. The susceptibility to antibiotics with increased consumption was almost stable. Decreased trends were only found in K. pneumoniae to imipenem (81-71.3%, p=0.046) and cefoperazone/sulbactam (70.8-61.0%, p=0.014) and in Acinetobacter baumannii to cefoperazone/sulbactam (59-28%, p=0.007), which negatively correlated with the consumption of carbapenems (r=-0.649, p=0.042) and 3GCs/β-lactamase inhibitors (p<0.05), respectively. The consumption of glycopeptides even positively correlated with the growing susceptibility to vancomycin in Enterococcus faecium (r=0.633, p=0.049) and Enterococcus faecalis (r=0.752, p=0.012).

CONCLUSION

The susceptibility to antibiotics with decreased consumption increased remarkably, but maintained stable to those with growing consumption. The stricter management of carbapenems and 3GCs is necessary.

Carbapenem-resistant Pseudomonas aeruginosa and carbapenem use in Japan: an ecological study

Objective

This study focused on carbapenem resistance in Pseudomonas aeruginosa and examined potential ecological correlations with carbapenem use in Japan.

Methods

The proportion of carbapenem-resistant P. aeruginosa isolates from 2015 and 2016 by prefecture was obtained from the Japan Nosocomial Infections Surveillance system. Data on carbapenem use was obtained from the National Database of Health Insurance Claims. The correlation between the proportion of carbapenem-resistant isolates and carbapenem consumption was assessed in a cross-sectional manner. The study also collected information on other variables including the numbers of physicians, nurses and medical facilities per 100 000 individuals by prefecture.

Results

Both the proportion of carbapenem-resistant P. aeruginosa isolates and levels of carbapenem use were higher in western Japan. Using a multivariate model, only carbapenem use remained significantly associated with the proportion of carbapenem-resistant isolates.

Conclusions

Carbapenem use and the proportion of carbapenem-resistant P. aeruginosa isolates were positively correlated. By longitudinal data collection, this approach offers an avenue to establish causal links as the frequency of carbapenem-resistant P. aeruginosa isolates starts to change in the future.

Forecasting models of infections due to carbapenem-resistant Gram-negative bacteria in an intensive care unit in an endemic area

OBJECTIVES

The aim of this study was to forecast the monthly incidence rates of infections [infections/1000 bed-days (IBD)] due to carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA), carbapenem-resistant Acinetobacter baumannii (CRAB) and total carbapenem-resistant Gram-negative bacteria (CRGNB) in an endemic intensive care unit (ICU) during the subsequent year (December 2016-December 2017) following the observational period.

METHODS

A 52-month observational period (August 2012-November 2016) was used. Two forecasting models, including a simple seasonal model for CRGNB, CRKP and CRPA and Winters' additive model for CRAB infections, were applied.

RESULTS

The models predicted the highest infection rates for CRKP, CRAB and CRGNB in January and September 2017 (23.8/23.4, 24.6/28.5 and 46.8/46.7 IBD, respectively) and for CRPA in February and March 2017 (8.3 and 7.9, respectively). The highest observed rates for CRKP, CRAB and CRGNB were indeed in January and September 2017 (25.6/19.0, 34.2/23.8 and 59.8/42.8 IBD, respectively); and for CRPA in February and March of the same year (15.2 and 12.7, respectively). The increased rates may be associated with personnel's annual work programme and behavioural factors.

CONCLUSION

Forecasting models in endemic ICUs may assist in implementation strategies for infection control measures.

Antibiotic consumption and resistance of gram-negative pathogens (collateral damage)

Antibiotics are commonly prescribed in community and hospital care. Overuse and misuse favors emergence and spread of resistant bacteria. The ATC/DDD methodology is commonly used for presenting the drug utilization data. In primary care, the consumption is usually expressed in DDD per 1,000 inhabitants per day, in hospital, preferably in DDD per 100 bed days and DDD per 100 admissions. The alternative metric is days of therapy (DOT), which needs IT support. Antibiotics have ecological adverse effects at individual and population level. Antibiotics select resistant bacteria among pathogens and normal flora. Broad-spectrum antibiotics, low dosage and prolonged antibiotic therapy favor the development of resistance. Although total use of antibiotics in hospital is much less than in the community, the intensity of use magnified by cross infection ensures a multitude of resistant bacteria in today's hospitals. Reversal of resistance is complex and might persist for many years despite the introduction of antimicrobial containment and stewardship programs.

Are antimicrobial stewardship programs effective strategies for preventing antibiotic resistance? A systematic review

BACKGROUND

Antimicrobial stewardship programs (ASPs) have been proposed as a solution for the global burden of antibiotic resistance, despite the lack of evidence on the subject.

OBJECTIVE

To analyze the role of ASPs in reducing bacterial resistance to antibiotics in hospital settings.

DATA SOURCES

A review in PubMed, Scopus, LILACS, and SciELO databases was performed. The period analyzed was January 1, 2012-January 4, 2017.

ELIGIBILITY CRITERIA

Studies that related ASPs to bacterial resistance.

DATA EXTRACTION

All studies that did not focus on ASPs were removed. Antifungal and antiviral programs were excluded.

RESULTS

Only 8 studies had quasi-experimental designs, and none were controlled trials. ASP strategies and microorganism-antibiotic pairs evaluated varied widely. Seven studies were classified as presenting clearly positive results, 3 had limited positive results, 7 had doubtful results, 4 had negative results, and 5 had noninterpretable results. The implementation of new infection control practices occurred in 7 studies.

LIMITATIONS

There are yet few studies on this matter, and most of them have inadequate study designs. Great heterogeneity between study features was detrimental to drawing evidence-based conclusions.

CONCLUSIONS

There is no solid evidence that ASPs are effective in reducing antibiotic resistance in hospital settings. We uphold the need for more studies with appropriate study designs, standardized ASP interventions targeting common microorganism-antibiotic pairs, and avoiding simultaneous implementation of infection control practices.

Colistin resistance in carbapenemase-producing Klebsiella pneumoniae bloodstream isolates: Evolution over 15 years and temporal association with colistin use by time series analysis

Colistin is often the only available treatment option against infections caused by carbapenemase-producing Klebsiella pneumoniae (CP-Kp). In this study, the evolution of colistin resistance among CP-Kp and its relationship with colistin use in a tertiary-care hospital in Athens, Greece, was investigated. All CP-Kp blood isolates recovered between January 2002 and June 2016 were tested for susceptibility to colistin by agar dilution and broth microdilution methods. Data on colistin use were collected from the pharmacy database. Time series of colistin use and resistance were analysed using the Box and Jenkins method. A transfer function model was built to quantify the dynamic relationship between colistin use and resistance. Overall, 313 CP-Kp isolates were identified. The percentage colistin resistance increased from 0% in 2002 to 26.9% in 2016 (R² = 0.5, P < 0.01). A temporal association between colistin use and resistance was observed; an increase in colistin use by 1 DDD/100 patient-days led to a 0.05 increase in the incidence rate of colistin resistance. The time lag between the effect of colistin use on subsequent variations in colistin resistance was 3 months. Colistin use and prior levels of colistin resistance could explain 69% of colistin resistance; in the remaining 31%, other factors might have played a role. The results presented here demonstrate a significant temporal association between colistin use and colistin resistance. These findings have important implications in implementing strategies to contain colistin resistance.

Sparing carbapenem usage

Background

Carbapenem resistance in Gram-negative bacteria is increasing in many countries and use of carbapenems and antibiotics to which resistance is linked should be reduced to slow its emergence. There are no directly equivalent antibiotics and the alternatives are less well supported by clinical trials. The few new agents are expensive.

Objectives

To provide guidance on strategies to reduce carbapenem usage.

Methods

A literature review was performed as described in the BSAC/HIS/BIA/IPS Joint Working Party on Multiresistant Gram-negative Infection Report.

Results

Older agents remain active against some of the pathogens, although expectations of broad-spectrum cover for empirical treatment have risen. Education, expert advice on treatment and antimicrobial stewardship can produce significant reductions in use.

Conclusions

More agents may need to be introduced onto the antibiotic formulary of the hospital, despite the poor quality of scientific studies in some cases.

Intensive care antibiotic consumption and resistance patterns: a cross-correlation analysis

Background

Over recent decades, a dramatic increase in infections caused by multidrug-resistant pathogens has been observed worldwide. The aim of the present study was to investigate the relationship between local resistance bacterial patterns and antibiotic consumption in an intensive care unit in a Romanian university hospital.

Methods

A prospective study was conducted between 1st January 2012 and 31st December 2013. Data covering the consumption of antibacterial drugs and the incidence density for the main resistance phenotypes was collected on a monthly basis, and this data was aggregated quarterly. The relationship between the antibiotic consumption and resistance was investigated using cross-correlation, and four regression models were constructed, using the SPSS version 20.0 (IBM, Chicago, IL) and the R version 3.2.3 packages.

Results

During the period studied, the incidence of combined-resistant and carbapenem-resistant P. aeruginosa strains increased significantly [(gradient = 0.78, R² = 0.707, p = 0.009) (gradient = 0.74, R² = 0.666, p = 0.013) respectively], mirroring the increase in consumption of β-lactam antibiotics with β-lactamase inhibitors (piperacillin/tazobactam) and carbapenems (meropenem) [(gradient = 10.91, R² = 0.698, p = 0.010) and (gradient = 14.63, R² = 0.753, p = 0.005) respectively]. The highest cross-correlation coefficients for zero time lags were found between combined-resistant vs. penicillins consumption and carbapenem-resistant P. aeruginosa strains vs. carbapenems consumption (0.876 and 0.928, respectively). The best model describing the relation between combined-resistant P. aeruginosa strains and penicillins consumption during a given quarter incorporates both the consumption and the incidence of combined-resistant strains in the hospital department during the previous quarter (multiple R² = 0.953, p = 0.017). The best model for explaining the carbapenem resistance of P. aeruginosa strains based on meropenem consumption during a given quarter proved to be the adjusted model which takes into consideration both previous consumption and incidence density of strains during the previous quarter (Multiple R² = 0.921, p = 0.037).

Conclusions

The cross-correlation coefficients and the fitted regression models provide additional evidence that resistance during the a given quarter depends not only on the consumption of antibacterial chemotherapeutic drugs in both that quarter and the previous one, but also on the incidence of resistant strains circulating during the previous quarter.

Electronic supplementary material

The online version of this article (10.1186/s12941-017-0251-8) contains supplementary material, which is available to authorized users.

Effect of antibiotic stewardship on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infection: a systematic review and meta-analysis

BACKGROUND

Antibiotic stewardship programmes have been shown to reduce antibiotic use and hospital costs. We aimed to evaluate evidence of the effect of antibiotic stewardship on the incidence of infections and colonisation with antibiotic-resistant bacteria.

METHODS

For this systematic review and meta-analysis, we searched PubMed, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Web of Science for studies published from Jan 1, 1960, to May 31, 2016, that analysed the effect of antibiotic stewardship programmes on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infections in hospital inpatients. Two authors independently assessed the eligibility of trials and extracted data. Studies involving long-term care facilities were excluded. The main outcomes were incidence ratios (IRs) of target infections and colonisation per 1000 patient-days before and after implementation of antibiotic stewardship. Meta-analyses were done with random-effect models and heterogeneity was calculated with the I² method.

FINDINGS

We included 32 studies in the meta-analysis, comprising 9 056 241 patient-days and 159 estimates of IRs. Antibiotic stewardship programmes reduced the incidence of infections and colonisation with multidrug-resistant Gram-negative bacteria (51% reduction; IR 0·49, 95% CI 0·35-0·68; p<0·0001), extended-spectrum β-lactamase-producing Gram-negative bacteria (48%; 0·52, 0·27-0·98; p=0·0428), and meticillin-resistant Staphylococcus aureus (37%; 0·63, 0·45-0·88; p=0·0065), as well as the incidence of C difficile infections (32%; 0·68, 0·53-0·88; p=0·0029). Antibiotic stewardship programmes were more effective when implemented with infection control measures (IR 0·69, 0·54-0·88; p=0·0030), especially hand-hygiene interventions (0·34, 0·21-0·54; p<0·0001), than when implemented alone. Antibiotic stewardship did not affect the IRs of vancomycin-resistant enterococci and quinolone-resistant and aminoglycoside-resistant Gram-negative bacteria. Significant heterogeneity between studies was detected, which was partly explained by the type of interventions and co-resistance patterns of the target bacteria.

INTERPRETATION

Antibiotic stewardship programmes significantly reduce the incidence of infections and colonisation with antibiotic-resistant bacteria and C difficile infections in hospital inpatients. These results provide stakeholders and policy makers with evidence for implementation of antibiotic stewardship interventions to reduce the burden of infections from antibiotic-resistant bacteria.

FUNDING

German Center for Infection Research.

Pseudomonas aeruginosa prevalence, antibiotic resistance and antimicrobial use in Chinese burn wards from 2007 to 2014

Objective To assess the application of antibacterial agents, alongside pathogen prevalence and Pseudomonas aeruginosa drug resistance, with the aim of understanding the impact of inappropriate antibacterial use. Methods This retrospective study assessed bacteria from wounds, catheters, blood, faeces, urine and sputum of hospitalized patients in burn wards between 2007 and 2014. The intensity of use of antibacterial agents and resistance of P. aeruginosa to common anti-Gram-negative antibiotics were measured. Results Annual detection rates of Staphylococcus aureus were significantly decreased, whereas annual detection rates of P. aeruginosa and Klebsiella pneumoniae were significantly increased. Multidrug-resistant strains of P. aeruginosa were increased. The intensity of use of some anti-Gramnegative antibiotics positively correlated with resistance rates of P. aeruginosa to similar antimicrobials. Conclusion In burn wards, more attention should be paid to P. aeruginosa and K. pneumoniae. The use of ciprofloxacin, ceftazidime and cefoperazone/sulbactam should be limited to counter the related increase in resistance levels.

Antimicrobial susceptibilities of aerobic and facultative gram-negative bacilli isolated from Chinese patients with urinary tract infections between 2010 and 2014

Background

The objective of this study was to investigate the distribution and susceptibility of aerobic and facultative Gram-negative bacilli isolated from Chinese patients with UTIs collected within 48 h (community acquired, CA) or after 48 h (hospital acquired, HA) of hospital admission.

Methods

From 2010 to 2014, the minimum inhibitory concentrations (MICs) of 12 antibiotics for 4,332 aerobic and facultative Gram-negative bacilli, sampled in 21 hospitals in 16 cities, were determined by the broth microdilution method.

Results

Enterobacteriaceae composed 88.5% of the total isolates, with Escherichia coli (E. coli) (63.2%) the most commonly isolated species, followed by Klebsiella pneumoniae (K. pneumoniae) (12.2%). Non-Enterobacteriaceae accounted for only 11.5% of all isolates and included mainly Pseudomonas aeruginosa (P. aeruginosa) (6.9%) and Acinetobacter baumannii (A. baumannii) (3.3%). Among the antimicrobial agents tested, the susceptibility rates of E.coli to the two carbapenems, ertapenem and imipenem as well as amikacin and piperacillin-tazobactam ranged from 92.5 to 98.7%. Against K. pneumonia, the most potent antibiotics were imipenem (92.6% susceptibility), amikacin (89.2% susceptibility) and ertapenem (87.9% susceptibility).

Although non-Enterobacteriaceae did not show high susceptibilities to the 12 common antibiotics, amikacin exhibited the highest in vitro activity against P. aeruginosa over the 5-year study period, followed by piperacillin-tazobactam, imipenem, ceftazidime, cefepime, ciprofloxacin, and levofloxacin. The Extended Spectrum Beta-Lactamase (ESBL) rates decreased slowly during the 5 years in E. coli from 68.6% in 2010 to 59.1% in 2014, in K. pneumoniae from 59.7 to 49.2%, and in Proteus mirabilis (P. mirabilis) from 40.0 to 26.1%. However, the ESBL rates were different in 5 regions of China (Northeast, North, East, South and Middle-China).

Conclusion

E. coli and K. pneumonia were the major pathogens causing UTIs and carbapenems and amikacin retained the highest susceptibility rates over the 5-year study period, indicating that they are good drug choices for empirical therapies, particularly of CA UTIs in China.

Investigating the Extremes of Antibiotic Use with an Epidemiologic Framework

Benchmarks for judicious use of antimicrobials are needed. Metrics such as defined daily doses (DDDs) and days of therapy (DOTs) quantify antimicrobial consumption. However, benchmarking with these metrics is complicated by interhospital variability. Thus, it is important for each hospital to monitor its own temporal consumption trends. Time series analyses allow trends to be detected; however, many of these methods are complex. We present simple regressive methods and caveats in using them to define potential antibiotic over- and underutilizations.

Antibiotic trends of Klebsiella pneumoniae and Acinetobacter baumannii resistance indicators in an intensive care unit of Southern Italy, 2008-2013

Background

The overuse of antimicrobials is one of the main factors responsible for the development and spread of antimicrobial resistance, together with other causes, such as intra- and inter-hospital spread of resistant microorganisms and infection control policies and practices. The objective of the present study is to report the trends of Klebsiella pneumoniae and Acinetobacter baumannii antimicrobial resistance indicators in an Italian intensive care unit (ICU) during a six-year period, from 2008 to 2013.

Methods

Susceptibility data and annual antibiotic consumptions in the ICU were retrospectively obtained from the clinical laboratory and the pharmacy. Trends over time of resistance rates (RRs) and of incidence densities of resistant isolates were determined by linear regression.

Results

Isolation density of A. baumannii increased significantly from 2008 (20.4 per 1,000 patient-days) to 2013 (58.1 per 1,000 patient-days) and of K. pneumoniae from 2010 (22.3 per 1,000 patient-days) to 2013 (55.9 per 1,000 patient-days). RRs of third-generation cephalosporins (3GCs)-resistant K. pneumoniae (from 2010: 41.9 %, to 2012: 87.0 %), of carbapenem-resistant K. pneumoniae (from 2008: 0 %, to 2013: 59.2 %), and of carbapenem-resistant A. baumannii (from 2008: 87.5 %, to 2013: 96.6 %) showed significant increasing trends. Carbapenems was the main antibiotic class consumed (24.9 % of the total antimicrobial usage density), followed by 3GCs (21.0 %), fluoroquinolones (20.6 %), aminoglycosides (17.3 %), penicillins (15.1 %) and glycopeptides (1.1 %). Carbapenems consumption decreased from 2008 to 2012 and then increased in 2013. Glycopeptides consumption decreased from 2008 to 2011 and then increased in 2013. Aminoglycosides consumption decreased from 2008 to 2010 and increased from 2012 to 2013. Finally, 3GC, penicillins and fluoroquinolones consumptions decreased from 2012 to 2013.

Conclusions

RRs of carbapenem-resistant A. baumannii and of carbapenem- and 3GC-resistant K. pneumoniae were higher than those for Europe. Our findings highlight the necessity to implement an integrated system for monitoring not only consumption of antibiotics and resistance profiles but also the clonality of alert microorganisms in the ICU for effective infection control.