Effect of different strategies for excluding duplicate cultures on the correlation between hospital resistance rates and antibiotic consumption

INTRODUCTION

Studies may underestimate the impact of antibiotics on bacterial resistance when correlating hospital antibiotic use with resistance rates (RRs) that exclude duplicate cultures as duplicates usually include more resistant isolates. Comparing correlations between antibiotic consumption and RRs resulting from different strategies for excluding duplicates could help explore how their exclusion affects such correlations.

METHODS

We obtained antibiotics consumption and Pseudomonas aeruginosa susceptibility data from 2017 to 2021 for seven antibiotics and for carbapenems as a group in a university hospital. We calculated RRs using seven different time criteria for excluding duplicates. We assessed the correlations of antibiotic consumption to the same-year and next-year RR rates for the three most distinct rates.

RESULTS

Duplicate cultures represented 53.45% of total cultures. RRs were higher when duplicates were included. We compared RRs resulting from excluding all duplicates, excluding duplicates monthly or admitting one culture per day. All antibiotics except meropenem showed a correlation with same-year RRs, either positive or negative, whereas all antibiotics showed a positive correlation with next-year RRs. For same-year and next-year correlations, the criteria with fewer duplicates (and therefore fewer resistant strains) found more correlations. However, the inclusion of duplicates taken at least 1 month apart found the most correlations. Admitting one culture per day found the fewest correlations.

CONCLUSIONS

Excluding duplicates from RRs affects the correlation of antibiotics consumption with RRs in P. aeruginosa. Including at least some duplicate cultures in correlation analyses, such as those taken 1 month apart, should be considered.

The effects of switching from ceftriaxone to cefotaxime on the occurrence of third-generation cephalosporin-resistant Enterobacterales: A stepped-wedge cluster randomized trial

OBJECTIVES

To evaluate the effects of the replacement of ceftriaxone by cefotaxime on the incidence of third-generation cephalosporin-resistant Enterobacterales (3GC-RE).

PATIENTS AND METHODS

We conducted a 24-month monocentric prospective, stepped-wedge cluster randomized controlled trial. During the control phase of the study, clinicians prescribed either ceftriaxone or cefotaxime. During the intervention phase, they systematically prescribed cefotaxime.

RESULTS

The cefotaxime/ceftriaxone ratio was inversely correlated with the incidence of 3GC-RE. All in all, 3GC-RE incidence was 1.05 (27/25,692) acquired cases/1000 hospitalization days during the control phase and 0.54 (11/20,419) acquired cases/1000 hospitalization days during the intervention phase (incidence rate ratio [IRR] = 0.51 [0.22-1.07], p = 0.06). In multivariable analysis, intervention phase (versus control phase) (p = 0.007), cefotaxime/ceftriaxone ratio (p = 0.003) and imported 3GC-RE (p = 0.005) were associated with the incidence of acquired cases of 3GC-RE.

CONCLUSIONS

We found that replacing ceftriaxone with cefotaxime reduced the occurrence of 3GC-RE isolates. More studies are needed to confirm these results.

Usefulness of dynamic regression time series models for studying the relationship between antimicrobial consumption and bacterial antimicrobial resistance in hospitals: a systematic review

BACKGROUNG

Antimicrobial resistance (AMR) is on the rise worldwide. Tools such as dynamic regression (DR) models can correlate antimicrobial consumption (AMC) with AMR and predict future trends to help implement antimicrobial stewardship programs (ASPs).

MAIN BODY

We carried out a systematic review of the literature up to 2023/05/31, searching in PubMed, ScienceDirect and Web of Science. We screened 641 articles and finally included 28 studies using a DR model to study the correlation between AMC and AMR at a hospital scale, published in English or French. Country, bacterial species, type of sampling, antimicrobials, study duration and correlations between AMC and AMR were collected. The use of β-lactams was correlated with cephalosporin resistance, especially in Pseudomonas aeruginosa and Enterobacterales. Carbapenem consumption was correlated with carbapenem resistance, particularly in Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. Fluoroquinolone use was correlated with fluoroquinolone resistance in Gram-negative bacilli and methicillin resistance in Staphylococcus aureus. Multivariate DR models highlited that AMC explained from 19 to 96% of AMR variation, with a lag time between AMC and AMR variation of 2 to 4 months. Few studies have investigated the predictive capacity of DR models, which appear to be limited.

CONCLUSION

Despite their statistical robustness, DR models are not widely used. They confirmed the important role of fluoroquinolones, cephalosporins and carbapenems in the emergence of AMR. However, further studies are needed to assess their predictive capacity and usefulness for ASPs.

Increased evidence for no benefit of contact precautions in preventing extended-spectrum β-lactamases-producing Enterobacteriaceae: Systematic scoping review

INTRODUCTION

Extended-spectrum β-lactamases-producing Enterobacteriaceae (ESBL-E) is a critical antimicrobial resistance pathogen, to which we need to pay the greatest attention. This study was aimed at uncovering the present evidence for the preventive effectiveness of contact precautions for patients colonized or infected with ESBL-E.

METHODS

According to the Preferred Reporting Items for Systemic Reviews and Meta-analyses (PRISMA) Extension for Scoping Reviews, we searched MEDLINE for articles with relevant keywords from the beginning of 2010 to October 18, 2022.

RESULTS

Of the 355 articles found, 9, including 8 observational studies and 1 randomized controlled trial, were selected. Safety of discontinuing contact precautions was evaluated mainly in acute-care and long-term care hospitals. Consistently, all authors concluded that contact precautions can be safely discontinued in patients colonized or infected with ESBL-E.

CONCLUSION

The clinical impact of discontinuing contact precautions for patients with ESBL-E is minimal and can be safely withdrawn at acute, noncritical, adult care wards. Relevant data from pediatric and geriatric wards, as well as intensive care units, were insufficient and should be investigated in future research.

Systematic review of time lag between antibiotic use and rise of resistant pathogens among hospitalized adults in Europe

Background

Antimicrobial resistance (AMR) causes substantial health and economic burden to individuals, healthcare systems and societies globally. Understanding the temporal relationship between antibiotic consumption and antibiotic resistance in hospitalized patients can better inform antibiotic stewardship activities and the time frame for their evaluation.

Objectives

This systematic review examined the temporal relationship between antibiotic use and development of antibiotic resistance for 42 pre-defined antibiotic and pathogen combinations in hospitalized adults in Europe.

Methods

Searches in MEDLINE, Embase, Cochrane Library and NIHR Centre for Reviews and Dissemination were undertaken from 2000 to August 2021. Pathogens of interest were Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus faecium, CoNS, Pseudomonas aeruginosa and Acinetobacter baumannii complex.

Results

Twenty-eight ecological studies and one individual-level study were included. Ecological studies were predominantly retrospective in design (19 studies) and of reasonable (20 studies) to high (8 studies) methodological quality. Of the eight pathogens of interest, no relevant data were identified for S. pneumoniae and CoNS. Across all pathogens, the time-lag data from the 28 ecological studies showed a similar pattern, with the majority of studies reporting lags ranging from 0 to 6 months.

Conclusions

Development of antibiotic resistance for the investigated antibiotic/pathogen combinations tends to occur over 0 to 6 months following exposure within European hospitals. This information could inform planning of antibiotic stewardship activities in hospital settings.

Limiting the Spread of Multidrug-Resistant Bacteria in Low-to-Middle-Income Countries: One Size Does Not Fit All

The spread of multidrug-resistant organisms (MDRO) is associated with additional costs as well as higher morbidity and mortality rates. Risk factors related to the spread of MDRO can be classified into four categories: bacterial, host-related, organizational, and epidemiological. Faced with the severity of the MDRO predicament and its individual and collective consequences, many scientific societies have developed recommendations to help healthcare teams control the spread of MDROs. These international recommendations include a series of control measures based on surveillance cultures and the application of barrier measures, ranging from patients' being isolated in single rooms, to the reinforcement of hand hygiene and implementation of additional contact precautions, to the cohorting of colonized patients in a dedicated unit with or without a dedicated staff. In addition, most policies include the application of an antimicrobial stewardship program. Applying international policies to control the spread of MDROs presents several challenges, particularly in low-to-middle-income countries (LMICs). Through a review of the literature, this work evaluates the real risks of dissemination linked to MDROs and proposes an alternative policy that caters to the means of LMICs. Indeed, sufficient evidence exists to support the theory that high compliance with hand hygiene and antimicrobial stewardship reduces the risk of MDRO transmission. LMICs would therefore be better off adopting such low-cost policies without necessarily having to implement costly isolation protocols or impose additional contact precautions.

A murine model to study the gut bacteria parameters during complex antibiotics like cefotaxime and ceftriaxone treatment

Background

The globally increasing resistance due to extended-spectrum beta-lactamase producing Enterobacteriaceae is a major concern. The objective of this work was to develop a murine model to study the gut bacteria parameters during complex antibiotics like cefotaxime and ceftriaxone treatment and to compare the fecal carriage of ESBL-producing Enterobacteriaceae.

Methods

SWISS mice were treated either with ceftriaxone or with cefotaxime or with NaCl 0.9% as a control group from day 1 to day 5. We performed a gavage at day 4 with a Klebsiella pneumonia CTX-M9. We collected stools and performed pharmacological measurements, cultures and 16S rRNA gene amplification and sequencing during the 12 days of the stool collection.

Results

Mice treated with ceftriaxone were more colonized than mice treated with cefotaxime after gavage (p-value = 0.008; Kruskal-Wallis test). Ceftriaxone and cefotaxime were both excreted in large quantity in gut lumen but they drove architecture of the gut microbiota in different trajectories. Highest levels of colonization were associated with particular microbiota composition using principal coordinate analysis (PCoA) which were more often achieved in ceftriaxone-treated mice and which were preceded by highest fecal antibiotics concentrations in both cefotaxime or ceftriaxone groups. Using LEfSe, we found that twelve taxa were significantly different between cefotaxime and ceftriaxone-treated mice. Using SplinectomeR, we found that relative abundances of Klebsiella were significantly higher in CRO than in CTX-treated mice (p-value = 0.01).

Conclusion

Ceftriaxone selects a particular microbial community and its substitution for cefotaxime could prevent the selection of extended-spectrum beta-lactamase producing Enterobacteriaceae.

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.

Role of surveillance cultures in infection control

Hospital-acquired infections are a known menace to the primary disease, for which a patient is admitted. These infections are twenty times more common in developing countries than in the developed ones. Surveillance for colonised patients can be passive or active process. In many hospitals, active surveillance culture for certain sentinel organisms followed by contact precautions for the same is an important part of infection control policy. Specific measures can be taken on early detection of multidrug-resistant organism, allowing prevention of widespread transmission in hospitals. Cultures are the most conventional and economical microbiological method of detection. The cost of active surveillance is a major challenge, especially for developing nations. These nations lack basic infrastructure and have logistic issues. The guidelines regarding this are not very clearly delineated for developing countries. Each hospital has its own challenges and the process is to be tailor-made accordingly. The following review delineates the various aspects of active surveillance for the colonisation of various organisms and the advantages and disadvantages of the same.

Antibiotic Resistance in Nosocomial Bacteria Isolated from Infected Wounds of Hospitalized Patients in Czech Republic

Hospitalized patients with wounds face an increased risk of infection with multi-drug-resistant nosocomial bacteria. In this study, samples from almost 10,000 patients from big hospitals in Czech Republic with infected wounds were analyzed for the presence of bacterial pathogens. In 7693 patients (78.8%), bacterial etiological agents were identified. Members of the Enterobacterales (37.1%) and Staphyloccus aureus (21.1%) were the most prevalent pathogens. Staphyloccus aureus showed methicillin resistance in 8.6%. Almost half of the Klebsiella pneumoniae isolates were ESBL-positive and 25.6% of the Enterobacter spp. isolates were AmpC-positive. The third most prevalent Pseudomonas aeruginosa showed resistance to 19-32% of the antipseudomonal antibiotics tested. Based on the results, amoxicillin/clavulanic acid, ampicillin/sulbactam or piperacillin/tazobactam combined with gentamicin can be recommended for antibiotic treatment of infected wounds. Once the etiological agent is identified, the therapy should be adjusted according to the species and its resistance.

Current status of post-operative infections due to antimicrobial-resistant bacteria after digestive tract surgery in Japan: Japan Postoperative Infectious Complications Survey in 2015 (JPICS'15)

PURPOSE

We herein report the findings of the Japan Postoperative Infectious Complication Survey in 2015 (JPICS'15), which evaluated the rate of post-operative infections and colonization due to antimicrobial-resistant (AMR) bacteria after digestive tract surgery.

METHODS

This survey by the Japan Society of Surgical Infection included patients undergoing digestive tract surgery at 28 centers between September 2015 and March 2016. Data included patient background characteristics, type of surgery, contamination status, and type of post-operative infections, including surgical site infections (SSIs), remote infections (RIs), and colonization.

RESULTS

During the study period, 7,565 surgeries (of 896 types) were performed; among them, 905 cases demonstrated bacteria after digestive tract surgery. The survey revealed that post-operative infections or colonization by AMR bacteria occurred in 0.9% of the patient cohort, constituting 7.5% of post-operative infections, including 5.6% of SSIs and 1.8% of RIs. Extended-spectrum β-lactamase-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus were the predominant AMR bacteria isolated from patients after digestive tract surgery. Patients infected with AMR bacteria had a poor prognosis.

CONCLUSION

Our results reveal that 7.5% of the post-operative infections were due to AMR bacteria, indicating the need for antibacterial coverage against AMR bacteria in patients with critical post-operative infections.

A Multidrug Resistance Plasmid pIMP26, Carrying blaIMP-26, fosA5, blaDHA-1, and qnrB4 in Enterobacter cloacae

IMP-26 was a rare IMP variant with more carbapenem-hydrolyzing activities, which was increasingly reported now in China. This study characterized a transferable multidrug resistance plasmid harboring bla_IMP-26 from one Enterobacter cloacae bloodstream isolate in Shanghai and investigated the genetic environment of resistance genes. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using broth microdilution method, Etest and PCR. The plasmid was analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis and hybridization. Whole genome sequencing and sequence analysis was conducted for further investigation of the plasmid. E. cloacae RJ702, belonging to ST528 and carrying bla_IMP-26, bla_DHA-1, qnrB4 and fosA5, was resistant to almost all β-lactams, but susceptible to quinolones and tigecycline. The transconjugant inherited the multidrug resistance. The resistance genes were located on a 329,420-bp IncHI2 conjugative plasmid pIMP26 (ST1 subtype), which contained trhK/trhV, tra, parA and stbA family operon. The bla_IMP-26 was arranged following intI1. The bla_DHA-1 and qnrB4 cluster was the downstream of ISCR1, same as that in p505108-MDR. The fosA5 cassette was mediated by IS4. This was the first report on complete nucleotide of a bla_IMP-26-carrying plasmid in E. cloacae in China. Plasmid pIMP26 hosted high phylogenetic mosaicism, transferability and plasticity.

Utilization of Vector Autoregressive and Linear Transfer Models to Follow Up the Antibiotic Resistance Spiral in Gram-negative Bacteria From Cephalosporin Consumption to Colistin Resistance

Background

Increasing antibiotic resistance may reciprocally affect consumption and lead to use of broader-spectrum alternatives; a vicious cycle that may gradually limit therapeutic options. Our aim in this study was to demonstrate this vicious cycle in gram-negative bacteria and show the utility of vector autoregressive (VAR) models for time-series analysis in explanatory and dependent roles simultaneously.

Methods

Monthly drug consumption data in defined daily doses per 100 bed-days and incidence densities of gram-negative bacteria (Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, and Acinetobacter baumannii) resistant to cephalosporins or to carbapenems were analyzed using VAR models. These were compared to linear transfer models used earlier.

Results

In case of all gram-negative bacteria, cephalosporin consumption led to increasing cephalosporin resistance, which provoked carbapenem use and consequent carbapenem resistance and finally increased colistin consumption, exemplifying the vicious cycle. Different species were involved in different ways. For example, cephalosporin-resistant Klebsiella spp. provoked carbapenem use less than E. coli, and the association between carbapenem resistance of P. aeruginosa and colistin use was weaker than that of A. baumannii. Colistin use led to decreased carbapenem use and decreased carbapenem resistance of P. aeruginosa but not of A. baumannii.

Conclusions

VAR models allow analysis of consumption and resistance series in a bidirectional manner. The reconstructed resistance spiral involved cephalosporin use augmenting cephalosporin resistance primarily in E. coli. This led to increased carbapenem use, provoking spread of carbapenem-resistant A. baumannii and consequent colistin use. Emergence of panresistance is fueled by such antibiotic-resistance spirals.

Cost-effectiveness of interventions to improve hand hygiene in healthcare workers in middle-income hospital settings: a model-based analysis

BACKGROUND

Multi-modal interventions are effective in increasing hand hygiene (HH) compliance among healthcare workers, but it is not known whether such interventions are cost-effective outside high-income countries.

AIM

To evaluate the cost-effectiveness of multi-modal hospital interventions to improve HH compliance in a middle-income country.

METHODS

Using a conservative approach, a model was developed to determine whether reductions in meticillin-resistant Staphylococcus aureus bloodstream infections (MRSA-BSIs) alone would make HH interventions cost-effective in intensive care units (ICUs). Transmission dynamic and decision analytic models were combined to determine the expected impact of HH interventions on MRSA-BSI incidence and evaluate their cost-effectiveness. A series of sensitivity analyses and hypothetical scenarios making different assumptions about transmissibility were explored to generalize the findings.

FINDINGS

Interventions increasing HH compliance from a 10% baseline to ≥20% are likely to be cost-effective solely through reduced MRSA-BSI. Increasing compliance from 10% to 40% was estimated to cost US$2515 per 10,000 bed-days with 3.8 quality-adjusted life-years (QALYs) gained in a paediatric ICU (PICU) and US$1743 per 10,000 bed-days with 3.7 QALYs gained in an adult ICU. If baseline compliance is not >20%, the intervention is always cost-effective even with only a 10% compliance improvement.

CONCLUSION

Effective multi-modal HH interventions are likely to be cost-effective due to preventing MRSA-BSI alone in ICU settings in middle-income countries where baseline compliance is typically low. Where compliance is higher, the cost-effectiveness of interventions to improve it further will depend on the impact on hospital-acquired infections other than MRSA-BSI.

High carriage rate of extended-spectrum beta-lactamase-producing Enterobacteriaceae among patients admitted for surgery in Tanzanian hospitals with a low rate of endogenous surgical site infections

INTRODUCTION

Despite the high reported rates of surgical site infections (SSIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (EPE) in low-income countries, including Tanzania, the role of EPE carriage in subsequent occurrence of SSIs is not known. This study investigated the rates of EPE carriage among surgical patients at the time of admission and discharge, and linked EPE genotype with SSIs.

METHODS

EPE were confirmed among isolates from rectal and wound/pus swabs using VITEK-2. Polymerase chain reaction and sequencing were performed to detect beta-lactamase genes. Multi-locus sequence typing was used to determine the genotypes of EPE isolates.

RESULTS

Among 930 patients enrolled, EPE carriage was significantly higher on discharge than admission (36.4% vs 23.7%, P<0.001). Of 272 patients who tested negative on admission, 78 (28.7%) acquired EPE during hospitalization. History of hospital stay within the previous three months was an independent predictor of EPE acquisition [hazard ratio 2, 95% confidence interval (CI) 1.04-3.98, P=0.038]. Of the 536 patients who were successfully followed-up after surgery, 78 (14.6%, 95% CI 11.6-17.5) developed SSIs. Of 57 SSIs investigated, 33 (58%) were caused by enteric Gram-negative bacteria, of which 63.6% (21/33) were EPE. Escherichia coli sequence type (ST)131 pandemic clone and Klebsiella pneumoniae ST391 predominated among wound isolates. The bla_CTX-M-15 gene was detected in 37 (97.3%) of 38 ESBL isolates. Male sex was an independent predictor of SSI (odds ratio 2.92, 95% CI 1.73-4.91, P<0.001).

CONCLUSION

These findings warrant implementation of strict infection control measures, antimicrobial stewardship and exploration of the transmission dynamics of EPE in surgical wards.

Is There an Association Between Use of Amoxicillin-Clavulanate and Resistance to Third-Generation Cephalosporins in Klebsiella pneumoniae and Escherichia coli at the Hospital Level?

AIMS

Amoxicillin-clavulanate is extensively used in European hospitals. Whether the hospital use of amoxicillin-clavulanate is associated with nonsusceptibility to third-generation cephalosporins (3GC) in Klebsiella pneumoniae is unknown. Our aim was to assess the relationship between the hospital use of amoxicillin-clavulanate and 3GC nonsusceptibility in K. pneumoniae and Escherichia coli.

METHODS

Yearly data of antibiotic use and 3GC nonsusceptibility in K. pneumoniae and E. coli were obtained from 33 French hospitals between 2011 and 2016. Decreased susceptibility to 3GC and Extended-Spectrum Beta-Lactamase (ESBL) production were modelled from antibiotic use with linear mixed models on years 2011 to 2015, and validated on year 2016.

RESULTS

Nonsusceptibility to 3GC increased in K. pneumoniae and E. coli. In a multivariable model that included year and use of 3GC and fluoroquinolones as explanatory variables, amoxicillin-clavulanate use was protective against 3GC nonsusceptibility in K. pneumoniae (incidence rate ratio [IRR], 0.992 [0.988-0.997]), and with ESBL production in K. pneumoniae (IRR, 0.989 [0.985-0.992]). The correlation coefficient between observed and predicted numbers of 3GC-nonsusceptible K. pneumoniae in 2016 was 0.95 (95% confidence interval, 0.89-0.98). There was no significant association between amoxicillin-clavulanate use and 3GC nonsusceptibility in E. coli.

CONCLUSION

Amoxicillin-clavulanate hospital use was protective against nonsusceptibility to 3GC in K. pneumoniae. Conversely, it was not associated with susceptibility to 3GC in E. coli. To decrease the hospital use of 3GC and fluoroquinolones, and 3GC nonsusceptibility in K. pneumoniae, it may be acceptable to increase the hospital use of amoxicillin-clavulanate. Interventional studies are necessary to confirm this hypothesis.

Changes in antimicrobial susceptibility of commonly clinically significant isolates before and after the interventions on surgical prophylactic antibiotics (SPAs) in Shanghai

Surveillances and interventions on antibiotics use have been suggested to improve serious drug-resistance worldwide. Since 2007, our hospital have proposed many measures for regulating surgical prophylactic antibiotics (carbapenems, third gen. cephalosporins, vancomycin, etc.) prescribing practices, like formulary restriction or replacement for surgical prophylactic antibiotics and timely feedback. To assess the impacts on drug-resistance after interventions, we enrolled infected patients in 2006 (pre-intervention period) and 2014 (post-intervention period) in a tertiary hospital in Shanghai. Proportions of targeted pathogens were analyzed: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus spp. (VRE), imipenem-resistant Escherichia coli (IREC), imipenem-resistant Klebsiella pneumoniae (IRKP), imipenem-resistant Acinetobacter baumannii (IRAB) and imipenem-resistant Pseudomonas aeruginosa (IRPA) isolates. Rates of them were estimated and compared between Surgical Department, ICU and Internal Department during two periods. The total proportions of targeted isolates in Surgical Department (62.44%, 2006; 64.09%, 2014) were more than those in ICU (46.13%, 2006; 50.99%, 2014) and in Internal Department (44.54%, 2006; 51.20%, 2014). Only MRSA has decreased significantly (80.48%, 2006; 55.97%, 2014) (p < 0.0001). The percentages of VRE and IREC in 3 departments were all <15%, and the slightest change were also both observed in Surgical Department (VRE: 0.76%, 2006; 2.03%, 2014) (IREC: 2.69%, 2006; 2.63%, 2014). The interventions on surgical prophylactic antibiotics can be effective for improving resistance; antimicrobial stewardship must be combined with infection control practices.

Prospective Validation of Cessation of Contact Precautions for Extended-Spectrum β-Lactamase-Producing Escherichia coli(1)

After contact precautions were discontinued, we determined nosocomial transmission of extended-spectrum β-lactamase (ESBL)–producing Escherichia coli by screening hospital patients who shared rooms with ESBL-producing E. coli–infected or –colonized patients. Transmission rates were 2.6% and 8.8% at an acute-care and a geriatric/rehabilitation hospital, respectively. Prolonged contact was associated with increased transmission.

Transmission of Resistant Gram-Negative Bacteria to Health Care Worker Gowns and Gloves during Care of Nursing Home Residents in Veterans Affairs Community Living Centers

The objectives of the study were to estimate the risk of transmission of antibiotic-resistant Gram-negative bacteria (RGNB) to gowns and gloves (G&G) worn by health care workers (HCWs) when providing care to nursing home residents and to identify the types of care and resident characteristics associated with transmission. A multicenter, prospective observational study was conducted with residents and HCWs from Veterans Affairs (VA) nursing homes. Perianal swabs to detect RGNB were collected from residents. HCWs wore G&G during usual care activities, and the G&G were swabbed at the end of the interaction in a standardized manner. Transmission of RGNB from a colonized resident to G&G by type of care was measured. Odds ratios (ORs) associated with type of care or resident characteristics were estimated. Fifty-seven (31%) of 185 enrolled residents were colonized with ≥1 RGNB. RGNB transmission to HCW gloves or gowns occurred during 9% of the interactions (n = 905): 7% to only gloves and 2% to only gowns. Bathing the resident and providing hygiene and toilet assistance were associated with a high risk of transmission. Glucose monitoring and assistance with feeding or medication were associated with a low risk of transmission. In addition, antibiotic use by the resident was strongly associated with greater transmission (OR, 2.51; P < 0.01). RGNB were transferred to HCWs during ∼9% of visits. High-risk types of care were identified for which use of G&G may be prioritized. Antibiotic use was associated with 2.5 times greater risk of transmission, emphasizing the importance of antibiotic stewardship. (This study has been registered at ClinicalTrials.gov under registration no. NCT01350479.).

Prevention of Infection Due to Clostridium difficile

Clostridium difficile is one of the foremost nosocomial pathogens. Preventing infection is particularly challenging. Effective prevention efforts typically require a multifaceted bundled approach. A variety of infection control procedures may be advantageous, including strict hand decontamination with soap and water, contact precautions, and using chlorine-containing decontamination agents. Additionally, risk factor reduction can help reduce the burden of disease. The risk factor modification is principally accomplished though antibiotic stewardship programs. Unfortunately, most of the current evidence for prevention is in acute care settings. This review focuses on preventative approaches to reduce the incidence of Clostridium difficile infection in healthcare settings.

Impact of monitoring surgical prophylactic antibiotics and a computerized decision support system on antimicrobial use and antimicrobial resistance

BACKGROUND

Monitoring of performance indicators and implementation of a computerized decision support system (CDSS) have been suggested as effective measures to improve quality of care. We conducted this study to evaluate the effect of monitoring of surgical prophylactic antibiotics (SPAs) and the CDSS on the antimicrobial use and resistance rate of major nosocomial pathogens.

METHODS

An interrupted time series with segmented regression analysis in 3 periods (preintervention, SPAs monitoring, and CDSS) was conducted in a tertiary care hospital. Immediate change and change in trends of antimicrobial use density, resistance rate of nosocomial pathogens, and cost of antibiotics in each intervention period were compared with those of the preintervention period.

RESULTS

Compared with the preintervention period, the change in the slope of the total use of antibiotics was -8.71 defined daily dose (DDD) per 1,000 patient days per month (95% confidence interval [CI], -11.43 to -5.98; P < .01) in the SPAs monitoring period and -1.95 DDD per 1,000 patient days per month (95% CI, -2.93 to -0.96; P < .01) in the CDSS period. Use of third-generation cephalosporins and aminoglycosides showed change comparable with that of total antibiotics use, but use of vancomycin and carbapenem was unchanged in the CDSS period. Trends of the proportions of extended-spectrum β-lactamase-producing Escherichia coli, meropenem-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus have been reversed or decreased in slope in the CDSS period. Length of hospital stay also showed a negative change in slope in the CDSS period.

CONCLUSIONS

Monitoring of SPAs and implementation of the CDSS can be effective measures for antimicrobial stewardship.

Clinical and Molecular Characteristics of Neonatal Extended-Spectrum β-Lactamase-Producing Gram-Negative Bacteremia: A 12-Year Case-Control-Control Study of a Referral Center in Taiwan

Extended-spectrum β-lactamase (ESBL)-producing Gram-negative bacteremia (GNB) in the neonatal intensive care unit was characterized by comparison with two control groups: a susceptible control group and a general base population group over 2001 to 2012. The influence of ESBL production on mortality was studied in all study subjects and ESBL-GNB isolates were microbiologically characterized. We identified 77 episodes of ESBL-GNB (14.2% of all neonatal late-onset GNB), which were caused by Klebsiella spp. (62.3%), E. coli (20.8%) and Enterobacter spp. (16.9%). Most ESBL-GNB strains were genetically unrelated and the SHV-type ESBLs were the most prevalent (67% of isolates). Comparison with both control groups disclosed previous usage of 3^rd generation cephalosporin (odds ratio [OR], 4.72; 95% confidence interval [CI], 2.03–10.97; P < 0.001), and underlying renal disease (OR, 4.07; 95% CI, 1.10–15.08; P = 0.035) as independent risk factors for ESBL-GNB. Inadequate empiric antibiotics, a higher illness severity, higher rates of infectious complications and sepsis-attributable mortality were more frequently seen in neonates with ESBL-GNB than those with non-ESBL GNB (20.8% and 15.6% vs. 9.2% and 7.9%, respectively; P = 0.008 and 0.049, respectively). Neonates with underlying secondary hypertension (OR, 7.22; 95% CI, 2.17–24.06) and infectious complications after bacteremia (OR, 6.66; 95% CI, 1.81–19.31) were identified as independent risk factor for in-hospital mortality. ESBL-GNB accounted for one-seventh of all neonatal gram-negative bacteremia, especially in neonates exposed to broad-spectrum cephalosporins. Neonates with ESBL-GNB bacteremia more frequently received inadequate empirical antibiotic therapy, which were associated with a higher rate of infectious complications and an adverse outcome.

Control of extended-spectrum β-lactamase-producing Enterobacteriaceae nosocomial acquisition in an intensive care unit: A time series regression analysis

BACKGROUND

This study was undertaken to determine the temporal relationship between implementation of different interventions in an intensive care unit (ICU) and control of endemic nosocomial acquisition of extended-spectrum β-lactamase Enterobacteriaceae (ESBLE).

METHODS

This was a prospective observational study with time-series analysis of the monthly incidence of ESBLE and its predictors. In November 2007, after a 14-month baseline period, an intervention consisting of restriction of third-generation cephalosporins (3 GC) and increased use of alcohol-based hand rubs was implemented. In January 2008, an increased health care worker (HCW):patient ratio was also implemented. In March 2010, the ICU was closed, and patients were moved to a clean ICU.

RESULTS

The first intervention resulted in global reduction in 3 GC and increased use of alcohol-based hand rub. A significant change in ESBLE incidence was observed in a full segmented univariate regression analysis (mean change in level, -0.91 ± 0.19; P < .0001). After ICU closure, there was a dramatic reduction in ESBLE acquisition. According to the multivariate model, the ICU closure was the main protective factor. Before ICU closure, an increase in the HCW:patient ratio of 0.1 point tended to be associated with a decreased risk of ESBLE acquisition (relative risk, 0.28; 95% confidence interval, 0.06-1.25; P = .09).

CONCLUSIONS

This study shows that ICU closure was associated with, but not necessarily the reason for, control of ESBLE cross-transmission in a nonoutbreak setting. Environmental ESBE sources may play a role in cross-transmission.

About the usefulness of contact precautions for carriers of extended-spectrum beta-lactamase-producing Escherichia coli

BACKGROUND

Extended-spectrum β-lactamases producing Escherichia coli (ESBL-E) are increasingly identified in health care facilities. As previously done for the control of methicillin-resistant Staphylococcus aureus, many hospitals have established screening strategies for early identification of patients being carriers of ESBL producers in general and ESBL-E in particular, and have implemented contact precautions (CP) for infected and colonized patients.

METHODS

The incidence of ESBL-E has been compared retrospectively between two French university hospitals (A and B) with different infection control policies over a 5-year long period of time (2006-2010).

RESULTS

While hospital A only implemented standard precautions after identification of patients colonized with ESBL-E, hospital B recommended additional CP. During the period of the study, the ESBL-E incidence rate significantly increased in both hospitals, but no significant difference was observed between the two hospitals.

CONCLUSIONS

This observational study did not reveal that additional CP measures had a greater impact on the incidence of ESBL-E in hospital settings.

Trends in Extended Spectrum Beta-Lactamase (ESBL) Producing Enterobacteriaceae and ESBL Genes in a Dutch Teaching Hospital, Measured in 5 Yearly Point Prevalence Surveys (2010-2014)

This paper describes the trends in prevalence of ESBL producing Enterobacteriaceae (ESBL-E) and ESBL genes, measured in five consecutive yearly Point Prevalence Surveys (PPS). All patients present in the hospital and in a day-care clinic (including patients on dialysis) on the day of the survey, were screened for perianal ESBL-E carriage. Perianal swabs were taken and cultured using an enrichment broth and a selective agar plate. Both phenotypic and genotypic methods were used to detect the production of ESBL, presence of ESBL-genes and clonal relatedness. Out of 2,695 patients, 135 (5.0%) were tested ESBL-E positive. The overall ESBL-E prevalence was stable over the years. Overall 5.2% of all ESBL-E were acquired by nosocomial transmission. A relative decrease of CTX-M-1-1-like ESBL genes (from 44 to 25%, p = 0.026) was observed, possibly related to the strong (>60%) decrease in antibiotic use in livestock in our country during the same period.

Systematic analysis of the relationship between antibiotic use and extended-spectrum beta-lactamase resistance in Enterobacteriaceae in a French hospital: a time series analysis

The influence of hospital use of antibiotics other than cephalosporins and fluoroquinolones on extended-spectrum beta-lactamase (ESBL) resistance among Enterobacteriaceae is poorly known. Our objective was to explore the association between ESBL and hospital use of various classes of antibacterial agents. The relationship between monthly use of 19 classes of antibacterial agents and incidence of nosocomial ESBL-producing Enterobacteriaceae in a French hospital was studied between 2007 and 2013. Five antibiotic classes were significantly and independently associated with ESBL resistance. Uses of tetracyclines (link estimate ± SE, 0.0066 ± 0.0033), lincosamides (0.0093 ± 0.0029), and other antibacterial agents (0.0050 ± 0.0023) were associated with an increased incidence, while nitrofurantoin (-0.0188 ± 0.0062) and ticarcillin and piperacillin with or without enzyme inhibitor (-0.0078 ± 0.0031) were associated with a decreased incidence. In a multivariate model including 3rd- and 4th-generation cephalosporins, fluoroquinolones, amoxicillin, and amoxicillin-clavulanate, 3rd- and 4th-generation cephalosporins (0.0019 ± 0.0009) and fluoroquinolones (0.0020 ± 0.0008) were associated with an increased ESBL resistance, whereas amoxicillin and amoxicillin-clavulanate were not. Hospital use of tetracyclines and lincosamides may promote ESBL resistance in Enterobacteriaceae. Nitrofurantoin and ticarcillin and piperacillin with or without enzyme inhibitor should be considered as potential alternatives to broad-spectrum cephalosporins and fluoroquinolones to control the diffusion of ESBL resistance.

High variability among Emergency Departments in 3rd-generation cephalosporins and fluoroquinolones use for community-acquired pneumonia

OBJECTIVE

Fluoroquinolones and 3rd-generation cephalosporins that are prescribed for pneumonia may be avoided and replaced by a penicillin in some cases. We aimed to determine if the proportion of patients treated for pneumonia with a cephalosporin, a fluoroquinolone or both varies among Emergency Departments (EDs), and to estimate the proportion of avoidable prescriptions.

METHODS

This was a retrospective study of patients treated for pneumonia in eight French EDs, and subsequently hospitalized in non-ICU wards. Third-generation cephalosporins or respiratory fluoroquinolones were presumed unavoidable if they met both criteria: (1) age ≥65 years or comorbid condition; and (2) allergy or intolerance to penicillin, or failure of penicillin, or previous treatment with penicillin, or for fluoroquinolones only, suspected legionellosis.

RESULTS

We included 832 patients. Thirty-four percent (95 % CI, 31-38 %) of patients were treated with a cephalosporin, a respiratory fluoroquinolone or both (range among EDs 19-44 %). Four EDs were independent risk factors for prescription of a cephalosporin, a fluoroquinolone or both [adjusted OR, 2.27 (1.64-3.15)], as were immune compromise [aOR 2.54 (1.56-4.14)], antibacterial therapy started before arrival in the ED [aOR 3.32 (2.30-4.81)], REA-ICU class III or IV [aOR 1.93 (1.15-3.23)], PSI class V [aOR 1.49 (1.00-2.20)], fluid resuscitation [aOR 3.98 (2.49-6.43)] and non-invasive ventilation in the ED [aOR, 7.18 (1.7-50.1)]. Treatment with a cephalosporin, a fluoroquinolone or both was avoidable in 67 % (62-73 %) of patients.

CONCLUSION

Cephalosporins and fluoroquinolones use in pneumonia is highly variable among EDs. The majority of these prescriptions are avoidable. Antibiotic stewardship programs should be implemented to restrict their use in EDs.

Infection control measures to decrease the burden of antimicrobial resistance in the critical care setting

PURPOSE OF REVIEW

The prevalence of multidrug-resistant organisms (MDROs) in ICUs is increasing worldwide. This review assesses the role of infection control measures, excluding antibiotic stewardship programs, in reducing the burden of resistance in ICUs.

RECENT FINDINGS

The knowledge base about the effect of increased hand hygiene compliance in reducing the burden of methicillin-resistant Staphylococcus aureus in ICUs has been improved. Universal decolonization with chlorhexidine body washing was associated with significant reduction in MDRO prevalence, but vigilance for emerging chlorhexidine resistance is required. A significant reduction of resistance for Gram-negative bacilli has been demonstrated with the use of selective decontamination, but further clinical trials are necessary before definitive conclusions can be drawn regarding long-term risk/benefit ratios.

SUMMARY

In the recent years, several high-quality clinical studies have assessed the ability of various infection control measures in reducing the burden of antimicrobial resistance. Significant progress has been made in identifying interventions effective in preventing transmission of MDROs in ICUs, in particular, decolonization. However, it still remains impossible to determine the exact and relative importance of different infection control measures. Any approach must ultimately be tailored to the local epidemiology of the targeted ICU.

Measuring Healthcare Worker Hand Hygiene Activity: Current Practices and Emerging Technologies

Monitoring hand hygiene compliance and providing healthcare workers with feedback regarding their performance are considered integral parts of multidisciplinary hand hygiene improvement programs. Observational surveys conducted by trained personnel are currently considered the “gold standard” method for establishing compliance rates, but they are time-consuming and have a number of shortcomings. Monitoring hand hygiene product consumption is less time-consuming and can provide useful information regarding the frequency of hand hygiene that can be used to give caregivers feedback. Electronic counting devices placed in hand hygiene product dispensers provide detailed information about hand hygiene frequency over time, by unit and during interventions. Electronic hand hygiene monitoring systems that utilize wireless systems to monitor room entry and exit of healthcare workers and their use of hand hygiene product dispensers can provide individual and unit-based data on compliance with the most common hand hygiene indications. Some systems include badges (tags) that can provide healthcare workers with real-time reminders to clean their hands upon entering and exiting patient rooms. Preliminary studies suggest that use of electronic monitoring systems is associated with increased hand hygiene compliance rates and that such systems may be acceptable to care givers. Although there are many questions remaining about the practicality, accuracy, cost, and long-term impact of electronic monitoring systems on compliance rates, they appear to have considerable promise for improving our efforts to monitor and improve hand hygiene practices among healthcare workers.

Management of multidrug resistant bacterial endemic

The fight against multi-drug resistant Gram-negative bacilli (MDRGNB), especially extended-spectrum β-lactamase producing Enterobacteriaceae, is about to be lost in our country. The emergence of new resistance mechanisms to carbapenems in these Enterobacteriaceae exposes patients to a risk of treatment failure without any other therapeutic options. This dramatic situation is paradoxical because we are well aware of the 2 major factors responsible for this situation: 1) MDRO cross-transmission, associated with a low compliance to standard precautions, especially hand hygiene, and 2) overexposure of patients to antibiotics. The implementation of a "search and isolate" policy, which was justified to control the spread of some MDRO that remained rare in the country, was not associated with a better adherence to standard precautions. The antibiotic policy and the measures implemented to control antibiotic consumptions have rarely been enforced and have shown inconsistent results. Notably, no significant decrease of antibiotic consumption has been observed. There is no excuse for these poor results, because some authors evaluating the effectiveness of programs for the control of MDRO have reported their positive effects on antimicrobial resistance without any detrimental effects. It is now urgent to deal with the 2 major factors by establishing an educational and persuasive program with quantified and opposable objectives. Firstly, we have to improve the observance of hand hygiene above 70%. Secondly, we have to define and reach a target for the reduction of antibiotic consumption both in community and in hospital settings.

Feasibility and impact of an intensified antibiotic stewardship programme targeting cephalosporin and fluoroquinolone use in a tertiary care university medical center

BACKGROUND

Restricted use of third-generation cephalosporins and fluoroquinolones has been linked to a reduced incidence of hospital-acquired infections with multidrug-resistant bacteria. We implemented an intensified antibiotic stewardship (ABS) programme in the medical service of a university hospital center aiming at a reduction by at least 30% in the use of these two drug classes.

METHODS

The ABS programme was focused on the 300-bed medical service. Prescription of third-generation cephalosporins was discouraged, whereas the use of penicillins was encouraged. Monthly drug use density was measured in WHO-ATC defined and locally recommended daily doses (DDD and RDD) per 100 patient days, to evaluate trends before (01/2008 to 10/2011) and after starting the intervention (1/2012 to 3/2013). The effect was analysed using interrupted time-series analysis with six non-intervention departments as controls.

RESULTS

Following initiation of the ABS intervention, overall antibiotic use in the medical service declined (p < 0.001). There was a significant intervention-related decrease in the use of cephalosporins and fluoroquinolones (p < 0.001) outperforming the decreasing baseline trend. Trend changes observed in some of the control departments were smaller, and the difference between trend changes in the medical service and those in control departments were highly significant for overall use and cephalosporin use reductions (p < 0.001) as well as for the increasing use of penicillins (p < 0.001). Mean use density levels (in RDD per 100 patient days) dropped for cephalosporins from 16.3 to 10.3 (-37%) and for fluoroquinolones from 17.7 to 10.1 (-43%), respectively. During the same period, the use of penicillins increased (15.4 to 18.2; 18%). The changes in expenditures for antibiotics in the medical service compared to control services minus programme costs indicated initial net cost savings likely to be associated with the programme.

CONCLUSION

An intensified ABS programme targeting cephalosporin und fluoroquinolone use in the setting of a large academic hospital is feasible and effective. The intervention may serve as a model for other services and hospitals with a similar structure and baseline situation.

Increasing use of third-generation cephalosporins for pneumonia in the emergency department: may some prescriptions be avoided?

Third-generation cephalosporins are used to treat inpatients with community-acquired pneumonia. Some of these prescriptions may be avoided, i.e. replaced by agents less likely to promote ESBL-mediated resistance. Our objectives were to assess the recent trend of third-generation cephalosporins use for pneumonia in the emergency department, and the proportion of avoidable prescriptions. This was a retrospective study of patients treated for community-acquired pneumonia in an emergency department, and subsequently hospitalized in non ICU wards. Third-generation cephalosporin prescriptions were presumed unavoidable if they met both criteria: (i) age ≥ 65 yr or comorbid condition, and (ii) allergy or intolerance to penicillin, or failure of penicillin first-line therapy, or treatment with penicillin in three previous months. Prescriptions were otherwise deemed avoidable. The proportion of patients treated with a third generation cephalosporin increased significantly from 13.9 % (6.9-24.1 %) in 2002 to 29.5 % (18.5-42.6 %) in 2012 (OR = 1.07 [1.01-1.14] , P = 0.02). This increase was independent from other factors associated with the prescription of a third-generation cephalosporin (immunocompromising condition, antibacterial therapy in three previous months, fluid resuscitation and REA-ICU class). Treatment with third-generation cephalosporin was avoidable in 118 out of 147 patients (80.3 % [72.7-86.2 %]). On day 7 after admission in the ED, treatment with third-generation cephalosporins was stopped or de-escalated in, respectively, 17 % and 32 % of patients. Antibiotic stewardship programs should be implemented to restrict the third-generation cephalosporins use for pneumonia in the emergency department.

Clustering of antimicrobial resistance outbreaks across bacterial species in the intensive care unit

BACKGROUND

There are frequent reports of intensive care unit (ICU) outbreaks due to transmission of particular antibiotic-resistant bacteria. Less is known about the burden of outbreaks of resistance due to horizontal transfer of mobile genetic elements between species. Moreover, the potential of existing statistical software as a preliminary means for detecting such events has never been assessed. This study uses a software package to determine the burden of species and resistance outbreaks in 2 adjacent ICUs and to look for evidence of clustering of resistance outbreaks consistent with interspecies transmission of resistance elements.

METHODS

A retrospective analysis of data from 2 adjacent 15-bed adult ICUs between 2002 and 2009 was undertaken. Detection of bacterial species-groups and resistance outbreaks was conducted using SaTScan and WHONet-SaTScan software. Resampling and permutation methods were applied to investigate temporal clustering of outbreaks.

RESULTS

Outbreaks occurred for 69% of bacterial species-groups (18/26), and resistance outbreaks were detected against 63% of antibiotics (10/16). Resistance outbreaks against 7 of 10 antibiotics were observed in multiple species-groups simultaneously and there was evidence of inter-species-group dependence for 4 of 7 antibiotics; background temporal changes in resistance did not explain the temporal aggregation of outbreaks in 3 of 7 antibiotics.

CONCLUSIONS

Species outbreaks occurred for the majority of bacteria commonly identified in the ICU. There was evidence for frequent temporal clustering of resistance outbreaks consistent with interspecies transmission of resistance elements. Wider application of outbreak detection software combined with targeted sequencing of bacterial genomes is needed to understand the contribution of interspecies gene transfer to resistance emergence.

Duration of colonization by extended-spectrum β-lactamase-producing Enterobacteriaceae after hospital discharge

BACKGROUND

The duration of gastrointestinal colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) may play a major role in the spread of these organisms. We evaluated the time to, and factors associated with, ESBL-E clearance after hospital discharge.

METHODS

We retrospectively reviewed prospective surveillance results obtained over 14 years in a 1,000-bed hospital. The surveillance collected demographic, hospital stay, microbiologic, and outcome data. An automatic alert system identified readmitted patients with prior ESBL-E carriage. ESBL-E clearance was defined as a negative rectal screening sample at readmission with no new positive clinical sample during the stay. Variables associated with ESBL-E clearance were identified using a Cox model.

RESULTS

We included 1,884 patients with 2,734 admissions. Four hundred forty-eight patients with readmission screening formed the basis for the study. Of 448 patients with 1 to 16 readmissions, 180 (40%) were persistent carriers. The median time to ESBL-E clearance was 6.6 months. Variables independently associated with clearance was having the first positive culture in a screening sample only (adjusted hazard ratio, 1.31; 95% confidence interval, 1.02-1.69; P = .04) and period 2005-2010 (hazard ratio, 1.88; 95% confidence interval, 1.33-2.67; P < .01).

CONCLUSION

We found a long duration of ESBL-E carriage after hospital discharge. An automatic alert system was useful for identifying, screening, and isolating previous ESBL-E carriers.

Has improved hand hygiene compliance reduced the risk of hospital-acquired infections among hospitalized patients in Ontario? Analysis of publicly reported patient safety data from 2008 to 2011

DESIGN

 Prospective, observational, ecological, time series, cross-sectional study examining the association between hand hygiene compliance (HHC) rates and the incidence of hospital-acquired infections.

SETTING

 Acute care hospitals (N = 166) located in the province of Ontario, Canada.

METHODS

 All data were extracted from the Ontario patient safety indicator database ( http://www.hqontario.ca/public-reporting/patient-safety). Complete data were available for 166 acute care hospitals from October 1, 2008, to December 31, 2011. The rates of Clostridium difficile infection (CDI) are reported monthly, methicillin-resistant Staphylococcus aureus (MRSA) bacteremia quarterly, and HHC rates yearly. Trends and associations for each indicator were evaluated by ordinary least squares regression (HHC), zero-inflated Poisson regression (MRSA bacteremia), or Poisson regression (CDI). Dependent variables included in the regression analyses were extracted from the same database and included year, healthcare region, and type of hospital (teaching or small or large community).

RESULTS

Compared to those in 2008, reported HHC rates improved every year both before and after environment/patient contact (range, 10.6%-25.3%). Compared to those in 2008, there was no corresponding change in the rates of MRSA bacteremia; however, the rates of CDI decreased in 2009 but were not statistically significantly decreased from baseline in either 2010 or 2011. No consistent association was demonstrated between changes in the rates of HHC and these two healthcare-associated infections (HAIs).

CONCLUSIONS

 Despite significant improvements in reported rates of HHC among healthcare personnel in Ontario's hospitals, we could not demonstrate a positive ecological impact on rates of these two HAIs.

Relationship between hospital antibiotic use and quinolone resistance in Escherichia coli

BACKGROUND

The relationship between the hospital use of various classes of antibiotics and resistance of Escherichia coli to quinolones remains debated. Our aim was to study the relationship between the hospital use of 16 classes of antibacterial agents and the incidence of quinolone-resistant E. coli isolates.

METHODS

Antibiotic use and resistance data were collected from 36 hospitals. Incident rate ratios (IRR) were assessed using negative binomial regression.

RESULTS

The incidence of quinolone-resistant isolates was independently associated with the consumption of tetracyclines (IRR 1.139, 95% CI 1.030-1.259), first- and second-generation cephalosporins (IRR 1.007, 95% CI 1.002-1.013), third-generation cephalosporins (IRR 1.029, 95% CI 1.010-1.048), and quinolones (IRR 1.007, 95% CI 1.000-1.014). These associations were independent from the type of patient served.

CONCLUSIONS

The level of hospital use of quinolones influences the incidence of quinolone resistance in E. coli hospital isolates. The consumption of two other classes of antibiotics, cephalosporins and tetracyclines, is also associated with quinolone resistance.

The impact of antibiotic use on the incidence and resistance pattern of extended-spectrum beta-lactamase-producing bacteria in primary and secondary healthcare settings

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• The emergence and spread of bacteria producing extended-spectrum beta-lactamases (ESBLs) has important therapeutic and epidemiologic implications. • A key target for the establishment of hospital antibiotic stewardship is reducing the occurrence of additional antibiotic resistance. • Further research is needed to accumulate supporting evidence that reducing antibiotic use will result in a parallel reduction in antibiotic resistance.

WHAT THIS STUDY ADDS

• Fluoroquinolone restriction reversed ciprofloxacin resistance in primary and secondary healthcare settings. • Fluoroquinolone restriction reduced ESBL-producing bacteria incidence rates in both the primary and secondary healthcare settings. • This study highlights the value of time-series analysis in designing efficient antibiotic stewardship.

AIMS

The objective of the present study was to study the relationship between hospital antibiotic use, community antibiotic use and the incidence of extended-spectrum beta-lactamase (ESBL)-producing bacteria in hospitals, while assessing the impact of a fluoroquinolone restriction policy on ESBL-producing bacteria incidence rates.

METHODS

The study was retrospective and ecological in design. A multivariate autoregressive integrated moving average (ARIMA) model was built to relate antibiotic use to ESB-producing bacteria incidence rates and resistance patterns over a 5 year period (January 2005-December 2009).

RESULTS

Analysis showed that the hospital incidence of ESBLs had a positive relationship with the use of fluoroquinolones in the hospital (coefficient = 0.174, P= 0.02), amoxicillin-clavulanic acid in the community (coefficient = 1.03, P= 0.03) and mean co-morbidity scores for hospitalized patients (coefficient = 2.15, P= 0.03) with various time lags. The fluoroquinolone restriction policy was implemented successfully with the mean use of fluoroquinolones (mainly ciprofloxacin) being reduced from 133 to 17 defined daily doses (DDDs)/1000 bed days (P < 0.001) and from 0.65 to 0.54 DDDs/1000 inhabitants/day (P= 0.0007), in both the hospital and its surrounding community, respectively. This was associated with an improved ciprofloxacin susceptibility in both settings [ciprofloxacin susceptibility being improved from 16% to 28% in the community (P < 0.001)] and with a statistically significant reduction in ESBL-producing bacteria incidence rates.

DISCUSSION

This study supports the value of restricting the use of certain antimicrobial classes to control ESBL, and demonstrates the feasibility of reversing resistance patterns post successful antibiotic restriction. The study also highlights the potential value of the time-series analysis in designing efficient antibiotic stewardship.