Impact of an intervention to control Clostridium difficile infection on hospital- and community-onset disease; an interrupted time series analysis

Core Elements for Implementing Antimicrobial Stewardship Programs in Korean General Hospitals

Currently, antimicrobial resistance (AMR) is a major threat to global public health. The antimicrobial stewardship program (ASP) has been proposed as an important approach to overcome this crisis. ASP supports the optimal use of antimicrobials, including appropriate dosing decisions, administration duration, and administration routes. In Korea, efforts are being made to overcome AMR using ASPs as a national policy. The current study aimed to develop core elements of ASP that could be introduced in domestic medical facilities. A Delphi survey was conducted twice to select the core elements through expert consensus. The core elements for implementing the ASP included (1) leadership commitment, (2) operating system, (3) action, (4) tracking, (5) reporting, and (6) education. To ensure these core elements are present at medical facilities, multiple departments must collaborate as teams for ASP operations. Establishing a reimbursement system and a workforce for ASPs are prerequisites for implementing ASPs. To ensure that ASP core elements are actively implemented in medical facilities, it is necessary to provide financial support for ASPs in medical facilities, nurture the healthcare workforce in performing ASPs, apply the core elements to healthcare accreditation, and provide incentives to medical facilities by quality evaluation criteria.

Association between consumption of antibiotics, infection control interventions and Clostridioides difficile infections: Analysis of six-year time-series data in a tertiary-care hospital in Greece

BACKGROUND

To investigate the association between Clostridioides difficile infection (CDI), antibiotic use, and infection control interventions, during an antibiotic stewardship program (ASP) implemented in a tertiary-care hospital in Greece from 2013 to 2018.

METHODS

Analysis was applied for the following monthly indices: 1. consumption of antibiotics; 2. use of hand hygiene disinfectant solutions; 3. percentage of isolations of patients either with multidrug-resistant (MDR) bacteria, or CDI, or admitted from another hospital; and 4. percentage of patients with CDI divided into two groups: community-acquired CDI (CACDI) and hospital-associated CDI (HACDI) (onset ≤72 h and >72 h after admission, respectively).

RESULTS

During the study, a significant reduction in CACDI rate from 0.3%/admissions [95% CI 0.1-0.6] to 0.1%/admissions [95% CI 0.0-0.3] (p-value = 0.035) was observed in adults ICU, while CDI rates were stable in the rest of the hospital. Antibiotic consumption showed a significant reduction in total hospital, from 91.7 DDDs [95% CI 89.7-93.7] to 80.1 DDDs [95% CI 79.1-81.1] (p-value<0.001), except adults ICU. Non-advanced antibiotics correlated with decreased CDI rates in Adults Clinic Departments and ICU. Isolation of patients one and two months earlier correlated with decreased CACDI rates per 20% [95% CI 0.64-1.00, p-value = 0.046] and HACDI per 23% [95% CI 0.60-1.00, p-value = 0.050] in Adults Clinic Departments. Consumption of disinfectant solutions current month correlated with decreased rate for CACDI per 33% [95% CI 0.49-0.91, p-value = 0.011] and HACDI per 38% [95% CI 0.40-0.98, p-value = 0.040] in total Hospital Clinics.

CONCLUSION

Rational antibiotic prescribing during ASP along with multipronged intervention strategy focusing on hand hygiene and patient isolation measures prevent and control CDI outbreaks in the hospital setting.

Effect of an Intensified Antibiotic Stewardship Program at an Orthopedic Surgery Department

Background: Institutional programs such as antibiotic stewardship (ABS) programs offer possibilities to monitor and modify antibiotic usage with the aim of reducing antibiotic resistance. In orthopedic units that treat peri-prosthetic joint infections (PJIs), ABS programs are still rare, however, there is extensive use of high-risk antibiotic agents and an increased risk for the occurrence of Clostridium difficile infections (CDIs). Patients and Methods: An ABS program was implemented at the Department of Orthopedic Surgery at a university hospital. Quarterly antibiotic consumption was measured in defined daily doses (DDDs) per 100 patient-days (PDs) at 10 quarters before the intervention and seven quarters after the intervention. The effect of the new antibiotic policy on drug use rates was evaluated using an interrupted time-series analysis. Estimated changes over time in the incidence of CDIs (cases per 1,000 PDs) were analyzed. Results: A remarkable percentual reduction in second-generation cephalosporin use of 83% (p < 0.001; pre-intervention level, 81.486 DDDs/100 patient-days; post-intervention level, 13.751 DDDs/100 PDs) and clindamycin administration of 78% (p < 0.001; pre-intervention level, 18.982 DDDs/100 PDs; post-intervention level, 4.216 DDDs/100 PDs) was observed after implementation of ABS interventions. Total antibiotic use declined by 25% (p < 0.001; pre-intervention level, 129.078 DDDs/100 PDs; post-intervention level, 96.826 DDDs/100 PDs). Conclusions: This research assessed the positive impact of an intensified ABS program at an orthopedic department specializing in PJIs. Antibiotic stewardship program interventions encourage the reduction of total antibiotic usage and especially high-risk antibiotic agents, associated with the development of antimicrobial resistance.

Guidelines on Implementing Antimicrobial Stewardship Programs in Korea

These guidelines were developed as a part of the 2021 Academic R&D Service Project of the Korea Disease Control and Prevention Agency in response to requests from healthcare professionals in clinical practice for guidance on developing antimicrobial stewardship programs (ASPs). These guidelines were developed by means of a systematic literature review and a summary of recent literature, in which evidence-based intervention methods were used to address key questions about the appropriate use of antimicrobial agents and ASP expansion. These guidelines also provide evidence of the effectiveness of ASPs and describe intervention methods applicable in Korea.

A systematic review of the effectiveness of cohorting to reduce transmission of healthcare-associated C. difficile and multidrug-resistant organisms

BACKGROUND

Cohorting of patients and staff is a control strategy often used to prevent the spread of infection in healthcare institutions. However, a comprehensive evaluation of cohorting as a prevention approach is lacking.

METHODS

We performed a systematic review of studies that used cohorting as part of an infection control strategy to reduce hospital-acquired infections. We included studies published between 1966 and November 30, 2019, on adult populations hospitalized in acute-care hospitals.

RESULTS

In total, 87 studies met inclusion criteria. Study types were quasi-experimental "before and after" (n = 35), retrospective (n = 49), and prospective (n = 3). Case-control analysis was performed in 7 studies. Cohorting was performed with other infection control strategies in the setting of methicillin-resistant Staphylococcus aureus (MRSA, n = 22), Clostridioides difficile infection (CDI, n = 6), vancomycin-resistant Enterococcus (VRE, n = 17), carbapenem-resistant Enterobacteriaceae infections (CRE, n = 22), A. baumannii (n = 15), and other gram-negative infections (n = 5). Cohorting was performed either simultaneously (56 of 87, 64.4%) or in phases (31 of 87, 35.6%) to help contain transmission. In 60 studies, both patients and staff were cohorted. Most studies (77 of 87, 88.5%) showed a decline in infection or colonization rates after a multifaceted approach that included cohorting as part of the intervention bundle. Hand hygiene compliance improved in approximately half of the studies (8 of 15) during the respective intervention.

CONCLUSION

Cohorting of staff, patients, or both is a frequently used and reasonable component of an enhanced infection control strategy. However, determining the effectiveness of cohorting as a strategy to reduce transmission of MDRO and C. difficile infections is difficult, particularly in endemic situations.

Prevention of Clostridium difficile Infection and Associated Diarrhea: An Unsolved Problem

For many years, it has been known that Clostridium difficile (CD) is the primary cause of health-care-associated infectious diarrhea, afflicting approximately 1% of hospitalized patients. CD may be simply carried or lead to a mild disease, but in a relevant number of patients, it can cause a very severe, potentially fatal, disease. In this narrative review, the present possibilities of CD infection (CDI) prevention will be discussed. Interventions usually recommended for infection control and prevention can be effective in reducing CDI incidence. However, in order to overcome limitations of these measures and reduce the risk of new CDI episodes, novel strategies have been developed. As most of the cases of CDI follow antibiotic use, attempts to rationalize antibiotic prescriptions have been implemented. Moreover, to reconstitute normal gut microbiota composition and suppress CD colonization in patients given antimicrobial drugs, administration of probiotics has been suggested. Finally, active and passive immunization has been studied. Vaccines containing inactivated CD toxins or components of CD spores have been studied. Passive immunization with monoclonal antibodies against CD toxins or the administration of hyperimmune whey derived from colostrum or breast milk from immunized cows has been tried. However, most advanced methods have significant limitations as they cannot prevent colonization and development of primary CDI. Only the availability of vaccines able to face these problems can allow a resolutive approach to the total burden due to this pathogen.

Impact of dedicated infectious disease teamwork on the treatment and prognosis of patients with diabetic foot infection

OBJECTIVE

The aim was to develop and evaluate the impact of a new model in which the infectious disease (ID) physician and pharmacist work together to treat diabetic foot infections (DFIs).

METHODS

A quasi-experimental before-after study was conducted. The medical charts of inpatients with DFI admitted between April 1, 2017 and March 31, 2018 were reviewed retrospectively (control group, n = 30). Inpatients diagnosed with DFI between April 1, 2018 and March 31, 2019 were enrolled prospectively as the intervention group and received treatment through dedicated ID teamwork (intervention group, n = 35).

RESULTS

The distribution of infection severity and levels of metabolic criteria were similar in the two groups. Compared with the control group, the intervention group received adequate initial empirical treatment more frequently (96.8% vs 43.5%, p < 0.001) and had a shorter median duration of fever (1 day vs 7.5 days, p < 0.001). Rates of healing and relapse within 6 months were similar in the two groups, although the intervention group showed more sites of osteomyelitis (p = 0.036) and a higher percentage of polymicrobial infections (48.6% vs 10.0%, p = 0.001).

CONCLUSION

The early and full participation of ID physicians and pharmacists in the treatment of DFI facilitated targeted antimicrobial treatment and improved patient outcomes.

Evaluation of a successful fluoroquinolone restriction intervention among high-risk patients: A mixed-methods study

Objective

We conducted a quality improvement initiative to restrict fluoroquinolone prescribing on two inpatient units housing high-risk patients and applied a human factors approach to understanding the barriers and facilitators to success of this intervention by front-line providers.

Methods

This was a mixed-methods, quasi-experimental study. This study was conducted on two inpatient units at a tertiary care academic medical center: the medical-surgical intensive care and abdominal solid organ transplant units. Unit-level data were collected retrospectively for 24 months pre- and post- fluoroquinolone restriction intervention, implemented in July 2016, for all admissions to the study units. Our restriction intervention required antimicrobial stewardship pre-approval for fluoroquinolone prescribing. We explored barriers and facilitators to optimal fluoroquinolone prescribing using semi-structured interviews attending, fellow and resident physicians, advanced practice providers and pharmacists on these units.

Results

Hospital-onset C. difficile infection did not decrease significantly, but fluoroquinolone use declined significantly from 111.6 to 19.8 days of therapy per 1000 patient-days without negatively impacting length of stay, readmissions or mortality. Third generation cephalosporin and aminoglycoside use increased post-restriction. Providers identified our institution’s strong antimicrobial stewardship program and pharmacy involvement in antimicrobial decision making as key facilitators of fluoroquinolone optimization and patient complexity, lack of provider education and organizational culture as barriers to optimal prescribing.

Conclusions

Fluoroquinolones can be safely restricted even among high-risk patients without negatively impacting length of stay, readmissions or mortality. Our study provides a framework for successful antimicrobial stewardship interventions informed by perceptions of front line providers.

The Effect of Clostridioides difficile Diagnostic Stewardship Interventions on the Diagnosis of Hospital-Onset Clostridioides difficile Infections

BACKGROUND

Public reporting of Clostridioides difficile infection (CDI) using laboratory-identified events has led some institutions to revert from molecular-based tests to less sensitive testing modalities. At one academic medical center, researchers chose to use nucleic acid amplification test alone in CDI diagnosis with institutional protocols aimed at diagnostic stewardship.

METHODS

A single-center, quasi-experimental study was conducted to introduce and analyze the effects of various diagnostic stewardship interventions. In April 2017 an order report was created to inform providers of patients' recent bowel movements, laxative use, and prior Clostridioides difficile (CD) testing (Intervention 1). In November 2017 nursing staff were empowered to not send nondiarrheal stools for testing (Intervention 2). In February 2019, an interruptive alert was implemented to prevent testing that was not indicated (Intervention 3). CD testing rates and healthcare facility-onset CDI (HO-CDI) rates were compared before and after the interventions using one-way analysis of variance (ANOVA).

RESULTS

At baseline, testing for CD after 3 days of admission was performed at mean ± standard deviation of 15.9 ± 1.7 tests/1,000 patient-days. After Intervention 1, it decreased to 12.1 ± 1.1 tests. This further decreased to 10.6 ± 0.8 after Intervention 2 and to 8.1 ± 0.1 after Intervention 3 (p < 0.001). HO-CDI cases per 10,000 patient-days declined from 12.7 ± 1.4 cases at baseline to 10.7 ± 1.2 after Intervention 1, to 8.7 ± 2.4 after Intervention 2, and to 5.8 ± 0.2 after Intervention 3 (p = 0.03).

CONCLUSION

A multidisciplinary approach optimizing electronic health record support tools and leveraging nursing education can reduce both testing and HO-CDI rates while using the most sensitive testing modality.

Impact of infection control measures on the related costs and the amount of broad-spectrum antimicrobial agents used in a hospital: A time-series analysis

Health care-associated infections (HAIs) worsen patient prognoses and increase medical costs. Antimicrobial stewardship (AMS), which involves appropriate use of antimicrobial agents and antiseptics, may be beneficial for addressing the issue of HAIs. In hospitals, an infection control team (ICT) plays an important role on the appropriate use of antimicrobial agents and antiseptics based on AMS. We aimed to conduct a time-series analysis of the efficacies of infection control measures in terms of related costs, amount of broad-spectrum antimicrobial agents used (carbapenems and quinolones), and methicillin-resistant Staphylococcus aureus (MRSA) detection rates. This retrospective cross-sectional study included in-hospital patients treated at a single institute between January 2012 and December 2015. The intervention start point (initiation of infection control measures) was January 2014. All survey items were subjected to segmented regression analysis using an autoregressive integrated moving average (ARIMA) model. Differences between pre-intervention and postintervention levels and their trends were assessed, using a statistical significance cutoff of P < .05. The infection control costs demonstrated a significantly increasing trend, despite significant decreases in the amount of carbapenems used. Accordingly, the implementation of infection control measures was associated with increased costs, whereas carbapenem use decreased immediately after intervention. Postintervention levels, trends of quinolone use, or MRSA detection rates did not reveal significant changes. Although implementation of infection control measures induced gradual increases in related costs, these measures led to immediate reductions in carbapenem use. Our study findings will support the establishment of more effective and economical infection control measures.

Genomic Delineation of Zoonotic Origins of Clostridium difficile

Clostridium difficile is toxin-producing antimicrobial resistant (AMR) enteropathogen historically associated with diarrhea and pseudomembranous colitis in hospitalized patients. In recent years, there have been dramatic increases in the incidence and severity of C. difficile infection (CDI), and associated morbidity and mortality, in both healthcare and community settings. C. difficile is an ancient and diverse species that displays a sympatric lifestyle, establishing itself in a range of ecological niches external to the healthcare system. These sources/reservoirs include food, water, soil, and over a dozen animal species, in particular, livestock such as pigs and cattle. In a manner analogous to human infection, excessive antimicrobial exposure, particularly to cephalosporins, is driving the expansion of C. difficile in livestock populations worldwide. Subsequent spore contamination of meat, vegetables grown in soil containing animal feces, agricultural by-products such as compost and manure, and the environment in general (households, lawns, and public spaces) is contributing to a persistent community source/reservoir of C. difficile and the insidious rise of CDI in the community. The whole-genome sequencing era continues to redefine our view of this complex pathogen. The application of high-resolution microbial genomics in a One Health framework (encompassing clinical, veterinary, and environment derived datasets) is the optimal paradigm for advancing our understanding of CDI in humans and animals. This approach has begun to yield critical insights into the genetic diversity, evolution, AMR, and zoonotic potential of C. difficile. In Europe, North America, and Australia, microevolutionary analysis of the C. difficile core genome shows strains common to humans and animals (livestock or companion animals) do not form distinct populations but share a recent evolutionary history. Moreover, for C. difficile sequence type 11 and PCR ribotypes 078 and 014, major lineages of One Health importance, this approach has substantiated inter-species clonal transmission between animals and humans. These findings indicate either a zoonosis or anthroponosis. Moreover, they challenge the existing paradigm and the long-held misconception that CDI is primarily a healthcare-associated infection. In this article, evolutionary, and zoonotic aspects of CDI are discussed, including the anthropomorphic factors that contribute to the spread of C. difficile from the farm to the community.

Seasonality and community interventions in a mathematical model of Clostridium difficile transmission

BACKGROUND

Clostridium difficile infection (CDI) is the leading cause of antibiotic-associated diarrhoea with peak incidence in late winter or early autumn. Although CDI is commonly associated with hospitals, community transmission is important.

AIM

To explore potential drivers of CDI seasonality and the effect of community-based interventions to reduce transmission.

METHODS

A mechanistic compartmental model of C. difficile transmission in a hospital and surrounding community was used to determine the effect of reducing transmission or antibiotic prescriptions in these settings. The model was extended to allow for seasonal antibiotic prescriptions and seasonal transmission.

FINDINGS

Modelling antibiotic seasonality reproduced the seasonality of CDI, including approximate magnitude (13.9-15.1% above annual mean) and timing of peaks (0.7-1.0 months after peak antibiotics). Halving seasonal excess prescriptions reduced the incidence of CDI by 6-18%. Seasonal transmission produced larger seasonal peaks in the prevalence of community colonization (14.8-22.1% above mean) than seasonal antibiotic prescriptions (0.2-1.7% above mean). Reducing transmission from symptomatic or hospitalized patients had little effect on community-acquired CDI, but reducing transmission in the community by ≥7% or transmission from infants by ≥30% eliminated the pathogen. Reducing antibiotic prescription rates led to approximately proportional reductions in infections, but limited reductions in the prevalence of colonization.

CONCLUSION

Seasonal variation in antibiotic prescription rates can account for the observed magnitude and timing of C. difficile seasonality. Even complete prevention of transmission from hospitalized patients or symptomatic patients cannot eliminate the pathogen, but interventions to reduce transmission from community residents or infants could have a large impact on both hospital- and community-acquired infections.

Diagnostic stewardship of C. difficile testing: a quasi-experimental antimicrobial stewardship study

OBJECTIVE

We evaluated whether a diagnostic stewardship initiative consisting of ASP preauthorization paired with education could reduce false-positive hospital-onset (HO) Clostridioides difficile infection (CDI).

DESIGN

Single center, quasi-experimental study.

SETTING

Tertiary academic medical center in Chicago, Illinois.

PATIENTS

Adult inpatients were included in the intervention if they were admitted between October 1, 2016, and April 30, 2018, and were eligible for C. difficile preauthorization review. Patients admitted to the stem cell transplant (SCT) unit were not included in the intervention and were therefore considered a contemporaneous noninterventional control group.

INTERVENTION

The intervention consisted of requiring prescriber attestation that diarrhea has met CDI clinical criteria, ASP preauthorization, and verbal clinician feedback. Data were compared 33 months before and 19 months after implementation. Facility-wide HO-CDI incidence rates (IR) per 10,000 patient days (PD) and standardized infection ratios (SIR) were extracted from hospital infection prevention reports.

RESULTS

During the entire 52 month period, the mean facility-wide HO-CDI-IR was 7.8 per 10,000 PD and the SIR was 0.9 overall. The mean ± SD HO-CDI-IR (8.5 ± 2.0 vs 6.5 ± 2.3; P &lt; .001) and SIR (0.97 ± 0.23 vs 0.78 ± 0.26; P = .015) decreased from baseline during the intervention. Segmented regression models identified significant decreases in HO-CDI-IR (Pstep = .06; Ptrend = .008) and SIR (Pstep = .1; Ptrend = .017) trends concurrent with decreases in oral vancomycin (Pstep &lt; .001; Ptrend &lt; .001). HO-CDI-IR within a noninterventional control unit did not change (Pstep = .125; Ptrend = .115).

CONCLUSIONS

A multidisciplinary, multifaceted intervention leveraging clinician education and feedback reduced the HO-CDI-IR and the SIR in select populations. Institutions may consider interventions like ours to reduce false-positive C. difficile NAAT tests.

Impact of antimicrobial stewardship interventions on Clostridium difficile infection and clinical outcomes: segmented regression analyses

Background

Antimicrobial exposure is associated with increased risk of Clostridium difficile infection (CDI), but the impact of prescribing interventions on CDI and other outcomes is less clear.

Objectives

To evaluate the effect of an antimicrobial stewardship intervention targeting high-risk antimicrobials (HRA), implemented in October 2008, and to compare the findings with similar studies from a systematic review.

Methods

All patients admitted to Medicine and Surgery in Ninewells Hospital from October 2006 to September 2010 were included. Intervention effects on HRA use (dispensed DDD), CDI cases and mortality rates, per 1000 admissions per month, were analysed separately in Medicine and Surgery using segmented regression of interrupted time series (ITS) data. Data from comparable published studies were reanalysed using the same method.

Results

Six months post-intervention, there were relative reductions in HRA use of 33% (95% CI 11-56) in Medicine and 32% (95% CI 19-46) in Surgery. At 12 months, there was an estimated reduction in CDI of 7.0 cases/1000 admissions [relative change -24% (95% CI - 55 to 6)] in Medicine, but no change in Surgery {estimated 0.1 fewer cases/1000 admissions [-2% (95% CI - 116 to 112)]}. Mortality reduced throughout the study period, unaffected by the intervention. In all six comparable studies, HRA use reduced significantly, but reductions in CDI rates were only statistically significant in two and none measured mortality. Pre-intervention CDI rates and trends influenced the intervention effect.

Conclusions

Despite large reductions in HRA prescribing and reductions in CDI, demonstrating real-world impact of stewardship interventions remains challenging.

ASID/ACIPC position statement - Infection control for patients with Clostridium difficile infection in healthcare facilities

BACKGROUND

In 2011, the Australasian Society for Infectious Diseases (ASID) and the Australian Infection Control Association (AICA), now known as the Australasian College of Infection Prevention and Control (ACIPC), produced a position statement on infection control requirements for preventing and controlling Clostridium difficile infection (CDI) in healthcare settings.

METHODS

The statement updated in 2017 to reflect new literature available .The authors reviewed the 2011 position statement and critically appraised new literature published between 2011 and 2017 and relevant current infection control guidelines to identify where new evidence had become available or best practice had changed.

RESULTS

The position statement was updated incorporating the new findings. A draft version of the updated position statement was circulated for consultation to members of ASID and ACIPC. The authors responded to all comments received and updated the position statement.

CONCLUSIONS

This updated position statement emphasizes the importance of health service organizations having evidence-based infection prevention and control programs and comprehensive antimicrobial stewardship programs, to ensure the risk of C. difficile acquisition, transmission and infection is minimised.

Rapid diagnostics for bloodstream infections: A primer for infection preventionists

Accurate and rapid antimicrobial susceptibility testing with pathogen identification in bloodstream infections is critical to life results for early sepsis intervention. Advancements in rapid diagnostics have shortened the time to results from days to hours and have had positive effects on clinical outcomes and on efforts to combat antimicrobial resistance when paired with robust antimicrobial stewardship programs. This article provides infection preventionists with a working knowledge of available rapid diagnostics for bloodstream infections.

Clostridium Difficile Infection in Acute Care Hospitals: Systematic Review and Best Practices for Prevention

OBJECTIVE Prevention of Clostridium difficile infection (CDI) in acute-care hospitals is a priority for hospitals and clinicians. We performed a qualitative systematic review to update the evidence on interventions to prevent CDI published since 2009. DESIGN We searched Ovid, MEDLINE, EMBASE, The Cochrane Library, CINAHL, the ISI Web of Knowledge, and grey literature databases from January 1, 2009 to August 1, 2015. SETTING We included studies performed in acute-care hospitals. PATIENTS OR PARTICIPANTS We included studies conducted on hospitalized patients that investigated the impact of specific interventions on CDI rates. INTERVENTIONS We used the QI-Minimum Quality Criteria Set (QI-MQCS) to assess the quality of included studies. Interventions were grouped thematically: environmental disinfection, antimicrobial stewardship, hand hygiene, chlorhexidine bathing, probiotics, bundled approaches, and others. A meta-analysis was performed when possible. RESULTS Of 3,236 articles screened, 261 met the criteria for full-text review and 46 studies were ultimately included. The average quality rating was 82% according to the QI-MQCS. The most effective interventions, resulting in a 45% to 85% reduction in CDI, included daily to twice daily disinfection of high-touch surfaces (including bed rails) and terminal cleaning of patient rooms with chlorine-based products. Bundled interventions and antimicrobial stewardship showed promise for reducing CDI rates. Chlorhexidine bathing and intensified hand-hygiene practices were not effective for reducing CDI rates. CONCLUSIONS Daily and terminal cleaning of patient rooms using chlorine-based products were most effective in reducing CDI rates in hospitals. Further studies are needed to identify the components of bundled interventions that reduce CDI rates. Infect Control Hosp Epidemiol 2017;38:476-482.

First-year results of an antibiotic stewardship program in a Greek tertiary care hospital

The aim of this study was to investigate the effect of the implementation of an antibiotic stewardship program (ASP) on antibiotic consumption in our 428-bed hospital. The Infection Control Committee implemented an ASP beginning in January 2016, aiming to reduce inappropriate antibiotic use through improved prescribing practices. The ASP included both pre-authorization and prospective audit and feedback strategies. We collected pharmacy and hospital data for the years 2015 (pre-intervention) and 2016 (post-intervention). Consumption data were expressed as daily defined doses (DDDs) per 100 patient-days (PD) and the significance of the differences between 2015 and 2016 was assessed by paired t-test. Antibiotic resistance rates for the most important hospital pathogens were monitored for 2015-2016. The ASP effectively reduced consumption of most antimicrobials; total antibiotic use decreased by 16.7% (from 104.3 in 2015 to 86.9 DDDs/100 patient-days in 2016, p < 0.001) owing to reduction of 19.1% for non-restricted and 13.8% for restricted antibiotics. Important restricted antimicrobials, such as colistin, carbapenems, quinolones and tigecycline showed significantly decreased usage post-intervention. Significant changes in the resistance rates were not observed, except a decreasing trend for colistin and tigecycline (Acinetobacter baumannii and Klebsiella pneumoniae) and also vancomycin (enterococci). The ASP was successful in terms of reducing the antibiotic consumption for the first year of its implementation. Interestingly, antimicrobials requiring pre-authorization exhibited a lower reduction than other antibiotics. Potential effects of the ASP in reducing resistance rates remain to be shown.

Clostridium difficile infection: new approaches to prevention, non-antimicrobial treatment, and stewardship

INTRODUCTION

Despite the large amount of scientific publications exploring the epidemiology and the clinical management of Clostridium difficile (CD) infection, some issues remain unsolved or need further studies. The aim of this review is to give an update on the hot topics on CD prevention, including stewardship programs, and on the non-microbiological treatment of CD infection. Areas covered: This article will review the importance of minimizing the CD spore shedding in the healthcare environment for potentially reducing CD transmission. Moreover, antimicrobial stewardship programs aimed to reduce CD incidence will be reviewed. Finally, new strategies for reducing CD infection recurrence will be described. Expert commentary: Besides the basic infection control and prevention practices, including hand hygiene, contact isolation and environmental cleaning, in the prevention of CD infection other issues should be addressed including minimizing the spread of CD in the healthcare setting, and implementing the best strategy for reducing CD infection occurrence, including tailored antimicrobial stewardship programs. Regarding new advancements in treatment and management of CDI episodes, non-antimicrobial approaches seem to be promising in reducing and managing recurrent CD infection.

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.

Reducing Clostridium difficile in the Inpatient Setting: A Systematic Review of the Adherence to and Effectiveness of C. difficile Prevention Bundles

BACKGROUND Clostridium difficile infection (CDI) is the most common infectious cause of nosocomial diarrhea, and its prevention is an urgent public health priority. However, reduction of CDI is challenging because of its complex pathogenesis, large reservoirs of colonized patients, and the persistence of infectious spores. The literature lacks high-quality evidence for evaluating interventions, and many hospitals have implemented bundled interventions to reduce CDI with variable results. Thus, we conducted a systematic review to examine the components of CDI bundles, their implementation processes, and their impact on CDI rates. METHODS We conducted a comprehensive literature search of multiple computerized databases from their date of inception through April 30, 2016. The protocol was registered in PROSPERO, an international prospective register of systematic reviews. Bundle effectiveness, adherence, and study quality were assessed for each study meeting our criteria for inclusion. RESULTS In the 26 studies that met the inclusion criteria for this review, implementation and adherence factors to interventions were variably and incompletely reported, making study reproducibility and replicability challenging. Despite contextual differences and the variety of bundle components utilized, all 26 studies reported an improvement in CDI rates. However, given the lack of randomized controlled trials in the literature, assessing a causal relationship between bundled interventions and CDI rates is currently impossible. CONCLUSION Cluster randomized trials that include a rigorous assessment of the implementation of bundled interventions are urgently needed to causally test the effect of intervention bundles on CDI rates. Infect Control Hosp Epidemiol 2017;38:639-650.

Strategies to enhance rational use of antibiotics in hospital: a guideline by the German Society for Infectious Diseases

Introduction

In the time of increasing resistance and paucity of new drug development there is a growing need for strategies to enhance rational use of antibiotics in German and Austrian hospitals. An evidence-based guideline on recommendations for implementation of antibiotic stewardship (ABS) programmes was developed by the German Society for Infectious Diseases in association with the following societies, associations and institutions: German Society of Hospital Pharmacists, German Society for Hygiene and Microbiology, Paul Ehrlich Society for Chemotherapy, The Austrian Association of Hospital Pharmacists, Austrian Society for Infectious Diseases and Tropical Medicine, Austrian Society for Antimicrobial Chemotherapy, Robert Koch Institute.

Materials and methods

A structured literature research was performed in the databases EMBASE, BIOSIS, MEDLINE and The Cochrane Library from January 2006 to November 2010 with an update to April 2012 (MEDLINE and The Cochrane Library). The grading of recommendations in relation to their evidence is according to the AWMF Guidance Manual and Rules for Guideline Development.

Conclusion

The guideline provides the grounds for rational use of antibiotics in hospital to counteract antimicrobial resistance and to improve the quality of care of patients with infections by maximising clinical outcomes while minimising toxicity. Requirements for a successful implementation of ABS programmes as well as core and supplemental ABS strategies are outlined. The German version of the guideline was published by the German Association of the Scientific Medical Societies (AWMF) in December 2013.

Interventions to improve antibiotic prescribing practices for hospital inpatients

BACKGROUND

Antibiotic resistance is a major public health problem. Infections caused by multidrug-resistant bacteria are associated with prolonged hospital stay and death compared with infections caused by susceptible bacteria. Appropriate antibiotic use in hospitals should ensure effective treatment of patients with infection and reduce unnecessary prescriptions. We updated this systematic review to evaluate the impact of interventions to improve antibiotic prescribing to hospital inpatients.

OBJECTIVES

To estimate the effectiveness and safety of interventions to improve antibiotic prescribing to hospital inpatients and to investigate the effect of two intervention functions: restriction and enablement.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library), MEDLINE, and Embase. We searched for additional studies using the bibliographies of included articles and personal files. The last search from which records were evaluated and any studies identified incorporated into the review was January 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and non-randomised studies (NRS). We included three non-randomised study designs to measure behavioural and clinical outcomes and analyse variation in the effects: non- randomised trials (NRT), controlled before-after (CBA) studies and interrupted time series (ITS) studies. For this update we also included three additional NRS designs (case control, cohort, and qualitative studies) to identify unintended consequences. Interventions included any professional or structural interventions as defined by the Cochrane Effective Practice and Organisation of Care Group. We defined restriction as 'using rules to reduce the opportunity to engage in the target behaviour (or increase the target behaviour by reducing the opportunity to engage in competing behaviours)'. We defined enablement as 'increasing means/reducing barriers to increase capability or opportunity'. The main comparison was between intervention and no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed study risk of bias. We performed meta-analysis and meta-regression of RCTs and meta-regression of ITS studies. We classified behaviour change functions for all interventions in the review, including those studies in the previously published versions. We analysed dichotomous data with a risk difference (RD). We assessed certainty of evidence with GRADE criteria.

MAIN RESULTS

This review includes 221 studies (58 RCTs, and 163 NRS). Most studies were from North America (96) or Europe (87). The remaining studies were from Asia (19), South America (8), Australia (8), and the East Asia (3). Although 62% of RCTs were at a high risk of bias, the results for the main review outcomes were similar when we restricted the analysis to studies at low risk of bias.More hospital inpatients were treated according to antibiotic prescribing policy with the intervention compared with no intervention based on 29 RCTs of predominantly enablement interventions (RD 15%, 95% confidence interval (CI) 14% to 16%; 23,394 participants; high-certainty evidence). This represents an increase from 43% to 58% .There were high levels of heterogeneity of effect size but the direction consistently favoured intervention.The duration of antibiotic treatment decreased by 1.95 days (95% CI 2.22 to 1.67; 14 RCTs; 3318 participants; high-certainty evidence) from 11.0 days. Information from non-randomised studies showed interventions to be associated with improvement in prescribing according to antibiotic policy in routine clinical practice, with 70% of interventions being hospital-wide compared with 31% for RCTs. The risk of death was similar between intervention and control groups (11% in both arms), indicating that antibiotic use can likely be reduced without adversely affecting mortality (RD 0%, 95% CI -1% to 0%; 28 RCTs; 15,827 participants; moderate-certainty evidence). Antibiotic stewardship interventions probably reduce length of stay by 1.12 days (95% CI 0.7 to 1.54 days; 15 RCTs; 3834 participants; moderate-certainty evidence). One RCT and six NRS raised concerns that restrictive interventions may lead to delay in treatment and negative professional culture because of breakdown in communication and trust between infection specialists and clinical teams (low-certainty evidence).Both enablement and restriction were independently associated with increased compliance with antibiotic policies, and enablement enhanced the effect of restrictive interventions (high-certainty evidence). Enabling interventions that included feedback were probably more effective than those that did not (moderate-certainty evidence).There was very low-certainty evidence about the effect of the interventions on reducing Clostridium difficile infections (median -48.6%, interquartile range -80.7% to -19.2%; 7 studies). This was also the case for resistant gram-negative bacteria (median -12.9%, interquartile range -35.3% to 25.2%; 11 studies) and resistant gram-positive bacteria (median -19.3%, interquartile range -50.1% to +23.1%; 9 studies). There was too much variance in microbial outcomes to reliably assess the effect of change in antibiotic use. Heterogeneity of intervention effect on prescribing outcomesWe analysed effect modifiers in 29 RCTs and 91 ITS studies. Enablement and restriction were independently associated with a larger effect size (high-certainty evidence). Feedback was included in 4 (17%) of 23 RCTs and 20 (47%) of 43 ITS studies of enabling interventions and was associated with greater intervention effect. Enablement was included in 13 (45%) of 29 ITS studies with restrictive interventions and enhanced intervention effect.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that interventions are effective in increasing compliance with antibiotic policy and reducing duration of antibiotic treatment. Lower use of antibiotics probably does not increase mortality and likely reduces length of stay. Additional trials comparing antibiotic stewardship with no intervention are unlikely to change our conclusions. Enablement consistently increased the effect of interventions, including those with a restrictive component. Although feedback further increased intervention effect, it was used in only a minority of enabling interventions. Interventions were successful in safely reducing unnecessary antibiotic use in hospitals, despite the fact that the majority did not use the most effective behaviour change techniques. Consequently, effective dissemination of our findings could have considerable health service and policy impact. Future research should instead focus on targeting treatment and assessing other measures of patient safety, assess different stewardship interventions, and explore the barriers and facilitators to implementation. More research is required on unintended consequences of restrictive interventions.

Genome Analysis of Clostridium difficile PCR Ribotype 014 Lineage in Australian Pigs and Humans Reveals a Diverse Genetic Repertoire and Signatures of Long-Range Interspecies Transmission

Clostridium difficile PCR ribotype (RT) 014 is well-established in both human and porcine populations in Australia, raising the possibility that C. difficile infection (CDI) may have a zoonotic or foodborne etiology. Here, whole genome sequencing and high-resolution core genome phylogenetics were performed on a contemporaneous collection of 40 Australian RT014 isolates of human and porcine origin. Phylogenies based on MLST (7 loci, STs 2, 13, and 49) and core orthologous genes (1260 loci) showed clustering of human and porcine strains indicative of very recent shared ancestry. Core genome single nucleotide variant (SNV) analysis found 42% of human strains showed a clonal relationship (separated by ≤2 SNVs in their core genome) with one or more porcine strains, consistent with recent inter-host transmission. Clones were spread over a vast geographic area with 50% of the human cases occurring without recent healthcare exposure. These findings suggest a persistent community reservoir with long-range dissemination, potentially due to agricultural recycling of piggery effluent. We also provide the first pan-genome analysis for this lineage, characterizing its resistome, prophage content, and in silico virulence potential. The RT014 is defined by a large "open" pan-genome (7587 genes) comprising a core genome of 2296 genes (30.3% of the total gene repertoire) and an accessory genome of 5291 genes. Antimicrobial resistance genotypes and phenotypes varied across host populations and ST lineages and were characterized by resistance to tetracycline [tetM, tetA(P), tetB(P) and tetW], clindamycin/erythromycin (ermB), and aminoglycosides (aph3-III-Sat4A-ant6-Ia). Resistance was mediated by clinically important mobile genetic elements, most notably Tn6194 (harboring ermB) and a novel variant of Tn5397 (harboring tetM). Numerous clinically important prophages (Siphoviridae and Myoviridae) were identified as well as an uncommon accessory gene regulator locus (agr3). Conservation in the pathogenicity locus and S-layer correlated with ST affiliation, further extending the concept of clonal C. difficile lineages. This study provides novel insights on the genetic variability and strain relatedness of C. difficile RT014, a lineage of emerging One Health importance. Ongoing molecular and genomic surveillance of strains in humans, animals, food, and the environment is imperative to identify opportunities to reduce the overall CDI burden.

Effect of a national 4C antibiotic stewardship intervention on the clinical and molecular epidemiology of Clostridium difficile infections in a region of Scotland: a non-linear time-series analysis

BACKGROUND

Whereas many antibiotics increase risk of Clostridium difficile infection through dysbiosis, epidemic C difficile ribotypes characterised by multidrug resistance might depend on antibiotic selection pressures arising from population use of specific drugs. We examined the effect of a national antibiotic stewardship intervention limiting the use of 4C antibiotics (fluoroquinolones, clindamycin, co-amoxiclav, and cephalosporins) and other infection prevention and control strategies on the clinical and molecular epidemiology of C difficile infections in northeast Scotland.

METHODS

We did a non-linear time-series analysis and quasi-experimental study to explore ecological determinants of clinical burdens from C difficile infections and ribotype distributions in a health board serving 11% of the Scottish population. Study populations were adults (aged ≥16 years) registered with primary carer providers in the community (mean 455 508 inhabitants) or admitted to tertiary level, district general, or geriatric hospitals (mean 33 049 total admissions per month). A mixed persuasive-restrictive 4C antibiotic stewardship intervention was initiated in all populations on May 1, 2009. Other population-specific interventions considered included limiting indications for macrolide prescriptions, introduction of alcohol-based hand sanitiser, a national hand-hygiene campaign, national auditing and inspections of hospital environment cleanliness, and reminders to reduce inappropriate use of proton-pump inhibitors. The total effect of interventions was defined as the difference between observations and projected scenarios without intervention. Primary outcomes were prevalence density of C difficile infection per 1000 occupied bed-days in hospitals or per 100 000 inhabitant-days in the community.

FINDINGS

Between Jan 1, 1997, and Dec 31, 2012, we identified 4885 cases of hospital-onset C difficile infection among 1 289 929 admissions to study hospitals, and a further 1625 cases of community-onset C difficile infection among 455 508 adults registered in primary care. Use of 4C antibiotics was reduced by 50% in both hospitals (mean reduction 193 defined daily doses per 1000 occupied bed-days, 95% CI 45-328, p=0·008) and the community (1·85 defined daily doses per 1000 inhabitant-days, 95% CI 0·23-3·48, p=0·025) during antibiotic stewardship. Falling 4C use predicted rapid declines in multidrug-resistant ribotypes R001 and R027. Hospital-onset C difficile infection prevalence densities were associated with fluoroquinolone, third-generation cephalosporin, macrolides, and carbapenem use, exceeding hospital population specific total use thresholds. Community-onset C difficile infection prevalence density was predicted by recent hospital C difficile infection rates, introduction of mandatory surveillance in individuals older than 65 years, and primary-case use of fluoroquinolones and clindamycin exceeding total use thresholds. Compared with predictions without intervention, C difficile infection prevalence density fell by 68% (mean reduction 1·01 per 1000 occupied bed-days, 0·27-1·76, p=0·008) in hospitals and 45% (0·083, 0·045-0·121 cases per 100 000 inhabitant-days, p<0·0001) in the community, during antibiotic stewardship. We identified no significant effects from other interventions.

INTERPRETATION

Limiting population use of 4C antibiotics reduced selective pressures favouring multidrug-resistant epidemic ribotypes and was associated with substantial declines in total C difficile infections in northeast Scotland. Efforts to control C difficile through antibiotic stewardship should account for ribotype distributions and non-linear effects.

FUNDING

NHS Grampian Microbiology Endowment Fund.

Mathematical Modeling of the Transmission Dynamics of Clostridium difficile Infection and Colonization in Healthcare Settings: A Systematic Review

BACKGROUND

We conducted a systematic review of mathematical models of transmission dynamic of Clostridium difficile infection (CDI) in healthcare settings, to provide an overview of existing models and their assessment of different CDI control strategies.

METHODS

We searched MEDLINE, EMBASE and Web of Science up to February 3, 2016 for transmission-dynamic models of Clostridium difficile in healthcare settings. The models were compared based on their natural history representation of Clostridium difficile, which could include health states (S-E-A-I-R-D: Susceptible-Exposed-Asymptomatic-Infectious-Resistant-Deceased) and the possibility to include healthcare workers and visitors (vectors of transmission). Effectiveness of interventions was compared using the relative reduction (compared to no intervention or current practice) in outcomes such as incidence of colonization, CDI, CDI recurrence, CDI mortality, and length of stay.

RESULTS

Nine studies describing six different models met the inclusion criteria. Over time, the models have generally increased in complexity in terms of natural history and transmission dynamics and number/complexity of interventions/bundles of interventions examined. The models were categorized into four groups with respect to their natural history representation: S-A-I-R, S-E-A-I, S-A-I, and S-E-A-I-R-D. Seven studies examined the impact of CDI control strategies. Interventions aimed at controlling the transmission, lowering CDI vulnerability and reducing the risk of recurrence/mortality were predicted to reduce CDI incidence by 3-49%, 5-43% and 5-29%, respectively. Bundles of interventions were predicted to reduce CDI incidence by 14-84%.

CONCLUSIONS

Although CDI is a major public health problem, there are very few published transmission-dynamic models of Clostridium difficile. Published models vary substantially in the interventions examined, the outcome measures used and the representation of the natural history of Clostridium difficile, which make it difficult to synthesize results and provide a clear picture of optimal intervention strategies. Future modeling efforts should pay specific attention to calibration, structural uncertainties, and transparent reporting practices.

Dissimilar Fitness Associated with Resistance to Fluoroquinolones Influences Clonal Dynamics of Various Multiresistant Bacteria

Fitness cost associated with resistance to fluoroquinolones was recently shown to vary across clones of methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamase-producing Klebsiella pneumoniae. The resulting dissimilar fitness should have influenced the clonal dynamics and thereby the rates of resistance for these pathogens. Moreover, a similar mechanism was recently proposed for the emergence of the H30 and H30R lineages of ESBL-producing E. coli and the major international clone (ribotype 027) of Clostridium difficile. Furthermore, several additional international clones of various multiresistant bacteria are suspect to have been selected by an analogous process. An ability to develop favorable mutations in the gyrase and topoisomerase IV genes seems to be a prerequisite for pathogens to retain fitness while showing high-level resistance to fluoroquinolones. Since, the consumption of other "non-fluoroquinolone" groups of antibiotics have also contributed to the rise in resistance rates a more judicious use of antibiotics in general and of fluoroquinolones in particular could ameliorate the international resistance situation.

Implementing an Antibiotic Stewardship Program: Guidelines by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America

Evidence-based guidelines for implementation and measurement of antibiotic stewardship interventions in inpatient populations including long-term care were prepared by a multidisciplinary expert panel of the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America. The panel included clinicians and investigators representing internal medicine, emergency medicine, microbiology, critical care, surgery, epidemiology, pharmacy, and adult and pediatric infectious diseases specialties. These recommendations address the best approaches for antibiotic stewardship programs to influence the optimal use of antibiotics.

Effects of fluoroquinolone restriction (from 2007 to 2012) on Clostridium difficile infections: interrupted time-series analysis

BACKGROUND

Antimicrobial stewardship is a key component in the reduction of healthcare-associated infections, particularly Clostridium difficile infection (CDI). We successfully restricted the use of cephalosporins and, subsequently, fluoroquinolones. From an endemically high level of >280 cases per year in 2007-08, the number of CDIs reduced to 72 cases in 2011-12.

AIM

To describe the implementation and impact of fluoroquinolone restriction on CDI.

METHODS

This was an interrupted time-series analysis pre and post fluoroquinolone restriction for 60 months based on a Poisson distribution model.

FINDINGS

In June 2008, fluoroquinolone consumption halved to about 5 defined daily doses (DDD) per 100 occupied bed-days (OBD). This was followed by a significant fall in CDI number [rate ratio (RR): 0.332; 95% confidence interval (CI): 0.240-0.460] which remained low over the subsequent months. Subsequently, fluoroquinolone consumption was further reduced to about 2 DDD/100 OBD in June 2010 accompanied by further reduction in CDI rate (RR: 0.394; 95% CI: 0.199-0.781). In a univariate Poisson model the CDI rate was associated with fluoroquinolone usage (RR: 1.086; 95% CI: 1.077-1.094).

CONCLUSION

We conclude that in an environment where cephalosporin usage is already low, the reduction in fluoroquinolone usage was associated with an immediate, large, and significant reduction in CDI cases.

Antibiotic policies in acute English NHS trusts: implementation of 'Start Smart-Then Focus' and relationship with Clostridium difficile infection rates

OBJECTIVES

The objective of this study was to establish how antibiotic prescribing policies at National Health Service (NHS) hospitals match the England Department of Health 'Start Smart-Then Focus' recommendations and relate to Clostridium difficile infection (CDI) rates.

METHODS

Antibiotic pharmacists were surveyed regarding recommendations for empirical treatment of common syndromes ('Start Smart') and antimicrobial prescription reviews ('Focus') at their hospital trusts. If no response was provided, policy data were sought from trust websites and the MicroGuide app (Horizon Strategic Partners, UK). Empirical treatment recommendations were categorized as broad spectrum (a β-lactam penicillin/β-lactamase inhibitor, cephalosporin, quinolone or carbapenem) or narrow spectrum. CDI rates were gathered from the national mandatory surveillance system.

RESULTS

Data were obtained for 105/145 English acute hospital trusts (72%). β-Lactam/β-lactamase inhibitor combinations were recommended extensively. Only for severe community-acquired pneumonia and pyelonephritis were narrow-spectrum agents recommended first line at a substantial number of trusts [42/105 (40%) and 50/105 (48%), respectively]. Policies commonly recommended dual therapy with aminoglycosides and β-lactams for abdominal sepsis [40/93 trusts (43%)] and undifferentiated severe sepsis [54/94 trusts (57%)]. Most policies recommended treating for ≥ 7 days for most indications. Nearly all policies [100/105 trusts (95%)] recommended antimicrobial prescription reviews, but only 46/96 respondents (48%) reported monitoring compliance. Independent predictors of higher CDI rates were recommending a broad-spectrum regimen for community-acquired pneumonia (P=0.06) and, counterintuitively, a recommended treatment duration of <48 h for nosocomial pneumonia (P=0.01).

CONCLUSIONS

Hospital antibiotic policies in the NHS 'Start Smart' by recommending broad-spectrum antibiotics for empirical therapy, but this may have the unintended potential to increase the use of broad-spectrum antibiotics and risk of CDI unless better mechanisms are in place to improve 'Focus'.

Whole genome sequencing reveals potential spread of Clostridium difficile between humans and farm animals in the Netherlands, 2002 to 2011

Farm animals are a potential reservoir for human Clostridium difficile infection (CDI), particularly PCR ribotype 078 which is frequently found in animals and humans. Here, whole genome single-nucleotide polymorphism (SNP) analysis was used to study the evolutionary relatedness of C. difficile 078 isolated from humans and animals on Dutch pig farms. All sequenced genomes were surveyed for potential antimicrobial resistance determinants and linked to an antimicrobial resistance phenotype. We sequenced the whole genome of 65 C. difficile 078 isolates collected between 2002 and 2011 from pigs (n = 19), asymptomatic farmers (n = 15) and hospitalised patients (n = 31) in the Netherlands. The collection included 12 pairs of human and pig isolates from 2011 collected at 12 different pig farms. A mutation rate of 1.1 SNPs per genome per year was determined for C. difficile 078. Importantly, we demonstrate that farmers and pigs were colonised with identical (no SNP differences) and nearly identical (less than two SNP differences) C. difficile clones. Identical tetracycline and streptomycin resistance determinants were present in human and animal C. difficile 078 isolates. Our observation that farmers and pigs share identical C. difficile strains suggests transmission between these populations, although we cannot exclude the possibility of transmission from a common environmental source.

Risk of Clostridium difficile infection in hospitalized patients receiving metronidazole for a non-C difficile infection

BACKGROUND & AIMS

Antibiotics often are given to prevent infections but also constitute a risk factor for Clostridium difficile infection (CDI). Metronidazole is an effective treatment for CDI. We investigated whether prophylactic administration of metronidazole to patients before they receive other antibiotics reduces the risk of CDI.

METHODS

We performed a retrospective cohort analysis of data collected from 12,026 high-risk patients admitted to Cleveland Clinic Foundation Hospitals from 2008 through 2012. High-risk patients were defined as age 55 or older who received a broad-spectrum antibiotic (piperacillin-tazobactam or ciprofloxacin) and a gastric acid suppressant (a proton pump inhibitor or a histamine-2 receptor blocker) during their hospitalization. Development of CDI was compared between patients who received metronidazole for non-CDI indications before broad-spectrum antibiotics (n = 811) and those who did not (n = 11,215). Logistic regression was used to control for patient demographics and comorbidities.

RESULTS

The rate of CDI was 1.4% (n = 11) among the patients who received metronidazole for non-CDI indications and 6.5% (n = 728) among those who did not. This was observed to be an 80% reduction in CDI among patients who received metronidazole (odds ratio, 0.21; 95% confidence interval, 0.11-0.38; P < .001), adjusted for age, sex, and comorbidities.

CONCLUSIONS

Based on a retrospective analysis, metronidazole might be used to prevent CDI in certain high-risk patients. Prospective controlled trials are necessary before making further recommendations.

Analysis of interventions to reduce the incidence of Clostridium difficile infection at a London teaching hospital trust, 2003-2011

BACKGROUND

Since 2008 there has been a substantial fall in the incidence of Clostridium difficile infection (CDI) in the UK, though it is unclear what contribution local and governmental interventions have made to this reduction.

AIM

To assess the value of retrospective analysis using a segmented regression model and single factor analysis of variance (ANOVA) in assessing the impact of interventions to reduce hospital-acquired CDI.

METHODS

A retrospective time-series analysis of 28 interventions implemented over an eight-year period by a large teaching hospital trust. Single factor ANOVA was used to analyse the association between CDI rates and changes in antibiotic usage and hand hygiene compliance data.

FINDINGS

Whereas several interventions were associated with a reduction in CDI rates, insufficient time-points were available between interventions to allow meaningful interpretation of all the data. Reduction of cephalosporin and quinolone use was associated with reduction in CDI rates. There was little association between observed variations in hand hygiene compliance and CDI rates.

CONCLUSION

Though several interventions were associated with a reduction in CDI, this study illustrates the inherent limitations of retrospective time-series methodology for the investigation of infection control measures where large numbers of interventions are introduced over a short time-period. Single factor ANOVA demonstrated an association between fall in CDI and restriction of high-risk antibiotic use. Little association was demonstrated between compliance rates documented in hand hygiene audits and CDI, though compliance was relatively high throughout the period of study.

Antimicrobial Stewardship Programs: Appropriate Measures and Metrics to Study their Impact

Antimicrobial stewardship is a new field that struggles to find the right balance between meaningful and useful metrics to study the impact of antimicrobial stewardship programs (ASPs). ASP metrics primarily measure antimicrobial use, although microbiological resistance and clinical outcomes are also important measures of the impact an ASP has on a hospital and its patient population. Antimicrobial measures looking at consumption are the most commonly used measures, and are focused on defined daily doses, days of therapy, and costs, usually standardized per 1,000 patient-days. Each measure provides slightly different information, with their own upsides and downfalls. Point prevalence measurement of antimicrobial use is an increasingly used approach to understanding consumption that does not entirely rely on sophisticated electronic information systems, and is also replicable. Appropriateness measures hold appeal and promise, but have not been developed to the degree that makes them useful and widely applicable. The primary reason why antimicrobial stewardship is necessary is the growth of antimicrobial resistance. Accordingly, antimicrobial resistance is an important metric of the impact of an ASP. The most common approach to measuring resistance for ASP purposes is to report rates of common or important community- or nosocomial-acquired antimicrobial-resistant organisms, such as methicillin-resistant Staphylococcus aureus and Clostridium difficile. Such an approach is dependent on detection methods, community rates of resistance, and co-interventions, and therefore may not be the most accurate or reflective measure of antimicrobial stewardship interventions. Development of an index to reflect the net burden of resistance holds theoretical promise, but has yet to be realized. Finally, programs must consider patient outcome measures. Mortality is the most objective and reliable method, but has several drawbacks. Disease- or organism-specific mortality, or cure, are increasingly used metrics.

Effect of antibiotic stewardship programmes on Clostridium difficile incidence: a systematic review and meta-analysis

OBJECTIVES

Despite vigorous infection control measures, Clostridium difficile continues to cause significant disease burden. Antibiotic stewardship programmes (ASPs) may prevent C. difficile infections by limiting exposure to certain antibiotics. Our objective was to perform a meta-analysis of published studies to assess the effect of ASPs on the risk of C. difficile infection in hospitalized adult patients.

METHODS

Searches of PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature and two Cochrane databases were conducted to find all published studies on interventions related to antibiotic stewardship and C. difficile. Two investigators independently assessed study eligibility and extracted data. Risk of bias was assessed using the Downs and Black tool. Risk ratios were pooled using random effects models. Heterogeneity was evaluated using the I(2) statistic.

RESULTS

The final search yielded 891 articles; 78 full articles were reviewed and 16 articles were identified for inclusion. Included articles used quasi-experimental (interrupted time series or before-after) or observational (case-control) study designs. When the results of all studies were pooled in a random effects model, a significant protective effect (pooled risk ratio 0.48; 95% CI: 0.38, 0.62) was observed between ASPs and C. difficile incidence. When stratified by intervention type, a significant effect was found for restrictive ASPs (complete removal of drug or prior approval requirement). Furthermore, ASPs were particularly effective in geriatric settings.

CONCLUSIONS

Restrictive ASPs can be used to reduce the risk of C. difficile infection.

Influence of cohorting patients with Clostridium difficile infection on risk of symptomatic recurrence

BACKGROUND

Cohorting of patients with Clostridium difficile infection (CDI) is recommended when single side-rooms are unavailable. Although patients may remain infectious after cessation of diarrhoea, continued cohorting may place them at increased risk of reinfection.

AIM

To identify risk factors for CDI recurrence and to determine whether cohorting of patients is associated with increased risk of recurrence.

METHODS

Data describing patient demographics, comorbidity, CDI severity and treatment were collected for 248 CDI patients at our hospital between October 2008 and June 2011. The primary outcome was symptomatic recurrence within 30 days of diagnosis.

FINDINGS

One hundred and thirty-eight (55.6%) CDI patients were admitted to the cohort ward. These patients were more likely to have severe CDI (odds ratio: 1.95; 95% confidence interval: 1.10-3.46; P = 0.022) and receive vancomycin (1.59; 0.94-2.68; P = 0.083) than patients who were not cohorted. Twenty-six patients (10.5%) suffered recurrence (21 cohorted and five not cohorted). Urinary infection on admission (5.16; 2.10-12.64; P < 0.001), cohorting (3.77; 1.37-10.35; P = 0.01) and concomitant antibiotics (2.07; 0.91-4.72; P = 0.083) were associated with increased risk of recurrence. On multivariate analysis, cohorting (3.94; 1.23-12.65; P = 0.021) and urinary infection (4.27; 1.62-11.24; P = 0.003) were significant predictors of recurrence.

CONCLUSION

Patients admitted to a C. difficile cohort ward may be at increased risk of recurrence because they are at increased risk of reinfection. Hospitals using cohort wards to control C. difficile should manage patient flow through the cohort to minimize this risk.

Epidemiology, diagnosis and treatment of Clostridium difficile infection

Clostridium difficile infection (CDI) is considered to be the main cause of bacterial infectious diarrhea in nosocomial settings. Since the beginning of the new century a continuous rise in the incidence of severe CDI has been observed worldwide. Even though some CDI cases are not associated with previous antibiotic exposure, this remains as the principal risk factor for the development of CDI. The rate of recurrences represents perhaps one the most challenging aspect on the management of CDI. There are several microbiological tests available, but glutamate dehydrogenase antigen test can be selected as the first screening step in a diagnostic algorithm, with positive samples then confirmed using a toxin(s) test, to distinguish toxinogenic from nontoxinogenic CDI. Although metronidazole and vancomycin are and have been the mainstay treatment options for CDI, there are some unmet medical and therapeutical needs. Usually oral metronidazole is recommended for initial treatment of nonsevere CDI and vancomycin for treatment of severe disease. Fidaxomicin may be considered in patients who cannot tolerate vancomycin, although more data are needed. For treatment of a nonsevere initial recurrence of CDI, oral metronidazole should be used, but for treatment of subsequent recurrences or more severe cases fidaxomicin may be helpful.

Interventions to improve antibiotic prescribing practices for hospital inpatients

BACKGROUND

The first publication of this review in Issue 3, 2005 included studies up to November 2003. This update adds studies to December 2006 and focuses on application of a new method for meta-analysis of interrupted time series studies and application of new Cochrane Effective Practice and Organisation of Care (EPOC) Risk of Bias criteria to all studies in the review, including those studies in the previously published version. The aim of the review is to evaluate the impact of interventions from the perspective of antibiotic stewardship. The two objectives of antibiotic stewardship are first to ensure effective treatment for patients with bacterial infection and second support professionals and patients to reduce unnecessary use and minimize collateral damage.

OBJECTIVES

To estimate the effectiveness of professional interventions that, alone or in combination, are effective in antibiotic stewardship for hospital inpatients, to evaluate the impact of these interventions on reducing the incidence of antimicrobial-resistant pathogens or Clostridium difficile infection and their impact on clinical outcome.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE from 1980 to December 2006 and the EPOC specialized register in July 2007 and February 2009 and bibliographies of retrieved articles. The main comparison is between interventions that had a restrictive element and those that were purely persuasive. Restrictive interventions were implemented through restriction of the freedom of prescribers to select some antibiotics. Persuasive interventions used one or more of the following methods for changing professional behaviour: dissemination of educational resources, reminders, audit and feedback, or educational outreach. Restrictive interventions could contain persuasive elements.

SELECTION CRITERIA

We included randomized clinical trials (RCTs), controlled clinical trials (CCT), controlled before-after (CBA) and interrupted time series studies (ITS). Interventions included any professional or structural interventions as defined by EPOC. The intervention had to include a component that aimed to improve antibiotic prescribing to hospital inpatients, either by increasing effective treatment or by reducing unnecessary treatment. The results had to include interpretable data about the effect of the intervention on antibiotic prescribing or microbial outcomes or relevant clinical outcomes.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and assessed quality. We performed meta-regression of ITS studies to compare the results of persuasive and restrictive interventions. Persuasive interventions advised physicians about how to prescribe or gave them feedback about how they prescribed. Restrictive interventions put a limit on how they prescribed; for example, physicians had to have approval from an infection specialist in order to prescribe an antibiotic. We standardized the results of some ITS studies so that they are on the same scale (percent change in outcome), thereby facilitating comparisons of different interventions. To do this, we used the change in level and change in slope to estimate the effect size with increasing time after the intervention (one month, six months, one year, etc) as the percent change in level at each time point. We did not extrapolate beyond the end of data collection after the intervention. The meta-regression was performed using standard weighted linear regression with the standard errors of the coefficients adjusted where necessary.

MAIN RESULTS

For this update we included 89 studies that reported 95 interventions. Of the 89 studies, 56 were ITSs (of which 4 were controlled ITSs), 25 were RCT (of which 5 were cluster-RCTs), 5 were CBAs and 3 were CCTs (of which 1 was a cluster-CCT).Most (80/95, 84%) of the interventions targeted the antibiotic prescribed (choice of antibiotic, timing of first dose and route of administration). The remaining 15 interventions aimed to change exposure of patients to antibiotics by targeting the decision to treat or the duration of treatment. Reliable data about impact on antibiotic prescribing data were available for 76 interventions (44 persuasive, 24 restrictive and 8 structural). For the persuasive interventions, the median change in antibiotic prescribing was 42.3% for the ITSs, 31.6% for the controlled ITSs, 17.7% for the CBAs, 3.5% for the cluster-RCTs and 24.7% for the RCTs. The restrictive interventions had a median effect size of 34.7% for the ITSs, 17.1% for the CBAs and 40.5% for the RCTs. The structural interventions had a median effect of 13.3% for the RCTs and 23.6% for the cluster-RCTs. Data about impact on microbial outcomes were available for 21 interventions but only 6 of these also had reliable data about impact on antibiotic prescribing.Meta-analysis of 52 ITS studies was used to compare restrictive versus purely persuasive interventions. Restrictive interventions had significantly greater impact on prescribing outcomes at one month (32%, 95% confidence interval (CI) 2% to 61%, P = 0.03) and on microbial outcomes at 6 months (53%, 95% CI 31% to 75%, P = 0.001) but there were no significant differences at 12 or 24 months. Interventions intended to decrease excessive prescribing were associated with reduction in Clostridium difficile infections and colonization or infection with aminoglycoside- or cephalosporin-resistant gram-negative bacteria, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. Meta-analysis of clinical outcomes showed that four interventions intended to increase effective prescribing for pneumonia were associated with significant reduction in mortality (risk ratio 0.89, 95% CI 0.82 to 0.97), whereas nine interventions intended to decrease excessive prescribing were not associated with significant increase in mortality (risk ratio 0.92, 95% CI 0.81 to 1.06).

AUTHORS' CONCLUSIONS

The results show that interventions to reduce excessive antibiotic prescribing to hospital inpatients can reduce antimicrobial resistance or hospital-acquired infections, and interventions to increase effective prescribing can improve clinical outcome. This update provides more evidence about unintended clinical consequences of interventions and about the effect of interventions to reduce exposure of patients to antibiotics. The meta-analysis supports the use of restrictive interventions when the need is urgent, but suggests that persuasive and restrictive interventions are equally effective after six months.

Use of a Microbiology Database to Analyse Changes in Resistance Patterns in the ICU

We combined our ICNARC dataset with a microbiology database in a mixed general and neurosurgical intensive care unit (ICU). We identified 1,097 positive tracheal aspirate cultures in 2,525 consecutive adult patients admitted over a three-year period. The database enabled us to track changes in tracheal aspirate flora and antibiotic resistance patterns following the introduction of a hospital-wide restrictive antibiotic policy targeted at Clostridium difficile infection (CDI) reduction. The pattern of organism types was unchanged although meticillin resistance in Staphylococcus aureus decreased from 33% to 17% (p=0.014). Sensitivity of tracheal aspirate cultures to empirical antibiotics increased from 67% to 86% in the first five days after hospital admission and from 53% to 81% in the subsequent five days. A combined microbiology/ICU database allowed resistance patterns to be identified within our unit. We believe this should be developed nationally both for research and for real time targeting of empiric antibiotic therapy.

Impact of an antibiotic restriction program on antibiotic utilization in the treatment of community-acquired pneumonia in a Veterans Affairs Medical Center

PURPOSE

The impact of an antibiotic restriction program (ARP) on the patterns of antibiotic use in the treatment of community-acquired pneumonia (CAP) was examined. We also evaluated the association between the ARP and the length of hospital stay in regard to CAP treatment and cost savings associated with the implementation of the ARP.

METHODS

A retrospective cohort study of patients admitted with CAP was conducted during two 6-month periods, one prior to the ARP and one after the ARP. The health system's computerized patient record system (CPRS) was used to obtain demographics, length of hospital stays, readmission rates, blood culture results, co-morbidities, antibiotic use, and durations of therapy. A total of 130 patients met the inclusion criteria for the final analyses. Average drug costs, employee salaries, and the cost of laboratory procedures were used to assess cost savings associated with the ARP.

RESULTS

From a total of 132 antibiotics that were ordered to treat CAP in the pre-ARP period, 28 were restricted (21.2%). However, the number of restricted antibiotics ordered was significantly reduced to 12 out of 114 (10.2%) antibiotics ordered in the post-ARP period (P = 0.024). In post-ARP implementation, the mean length of hospital stay was also significantly reduced from 7.6 to 5.8 days (P = 0.017), and although not statistically significant, the 30-day readmission rates declined from 16.9 to 6.2% (P = 0.097). The ARP was also associated with a saving of $943 per patient treated for CAP.

CONCLUSIONS

In addition to a decrease in the antibiotic utilization and the mean length of hospital stay, the ARP may have yielded cost savings and reduced the readmission rates for those patients admitted and treated for CAP.