Impact and cost of infection control measures to reduce nosocomial transmission of extended-spectrum beta-lactamase-producing organisms in a non-outbreak setting

Epidemiologic analysis of antimicrobial resistance in hospital departments in China from 2022 to 2023

Bacterial drug resistance monitoring in hospitals is a crucial aspect of healthcare management and a growing concern worldwide. In this study, we analysed the bacterial drug resistance surveillance in our hospital from 2022 Q1 to 2023 Q2. The main sampling sources were respiratory, blood, and urine-based, and the main clinical infections were respiratory and genitourinary in nature. Specimens were inoculated and cultured; bacterial strains were isolated using a VITEK® 2 Compact 60-card automatic microorganism identifier (bioMerieux, Paris, France) and their matching identification cards were identified, and manual tests were supplemented for strain identification. The most common Gram-positive bacteria detected were Staphylococcus aureus, followed by Enterococcus faecalis (E. faecalis), Staphylococcus epidermidis (S. epidermidis), and Staphylococcus haemolyticus (S. haemolyticus). The most common Gram-negative bacteria detected were Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The most prevalent multidrug-resistant bacteria were those producing extended-spectrum beta-lactamases, followed by methicillin-resistant Staphylococcus aureus, followed by carbapenem-resistant Enterobacterales. This study suggests that the prevention and control of infections in the respiratory and genitourinary systems should be the focus of anti-infective work and that the use of antimicrobials should be reduced and regulated to prevent the emergence and spread of resistant bacteria.

Cost analysis of a teaching hospital in Thailand: Impacts of the first wave of COVID-19

COVID-19 has had adverse impacts on the health sector in Thailand and information on hospital costs is required for planning and budgeting. The aim of this study was to estimate costs that the pandemic imposed on a teaching hospital in the country, focusing on the first wave which took place in March-May 2020. A retrospective cost analysis was performed. Data on COVID-related activities, including when and where they were undertaken, were retrieved from existing sources and supplemented by in-depth interviews with the hospital’s staff. The data collection period was January-October 2020, covering three distinct phases: before, during, and after the first wave of the pandemic. The total costs during the preparation phase in January-February, the pandemic phase in March-May, and the standby phase in June-October were 0.6, 3.9, and 1.2 million US dollars respectively. Costs related to treatment of COVID-19 patients were higher than those related to infection control in the first two phases but not in the standby phase, making up 82.09%, 75.23%, and 43.95% of the total costs in the three phases respectively. Costs were incurred in all areas of the hospital, including those that were set up to serve COVID patients, those serving non-COVID patients, and those serving both groups. Public donations were integral to the provision of services and made up 20.94% of the total cost during the pandemic phase. This study was the first to estimate hospital costs of COVID-19 in Thailand. It demonstrated high costs of a national outbreak and supported the establishment of a contingency fund for medical emergencies at the hospital level.

Conceptual framework of antibiotic stewardship programs in reducing ESBL-producing Enterobacteriaceae: a systematic review and meta-analysis

Today, the phenomenon of antibiotic resistance has become one of the main concerns of health system around the world. Antimicrobial stewardship programs (ASPs) are considered as the most important strategy in optimizing antibiotic consumption, which in turn reduce the emergence of multidrug/extensively drug-resistant (MDR/XDR) microorganisms, as well as reducing mortality and healthcare costs. However, the effectiveness of APSs in controlling the spread of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae has not been investigated. The pooled odds ratio for the effectiveness of ASPs in reducing ESBL-producing Enterobacteriaceae was 0.82 (95% CI: 0.70-0.98; P value: 0.03); our results showed that in group with implemented ASPs, the prevalence of infection associated with these bacteria had been reduced by 11.8%. Overall, antimicrobial stewardship strategies are significantly effective in reducing ESBL-producing Enterobacteriaceae infections. The present study concluded that a comprehensive stewardship program will certainly reduce the mortality rate, as well as hospitalization stay and treatment costs. In general, our findings strongly support the performance of ASPs in healthcare centers.

The Effect of Infection Precautions on Extended-Spectrum Beta-Lactamase Enterobacteriaceae Colonization Among Nurses in Three Beirut Hospitals

Background and objective

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) are rapidly emerging worldwide. This study aimed to assess the effect of contact precaution (CP) on ESBL-PE-colonization rates among nurses in three hospitals in Beirut, Lebanon, where ESBL is endemic, in order to define the risk factors for colonization. Accordingly, the ongoing use of CP to prevent ESBL-PE transmission to healthy nurses was evaluated.

Methods

This cross-sectional study was conducted in three hospitals. Hospital 1 required CP, Hospital 2 had recently stopped CP, and Hospital 3 had stopped it three years previously. Questionnaires and stool-collection containers were distributed to all patient care nurses in those three hospitals. The Returned samples were tested using the agar dilution technique.

Results

A total of 269 out of 733 nurses volunteered to participate; 140 met the inclusion criteria (no recent hospitalization, antibiotic use, or known ESBL-PE colonization) and provided samples. Among them, 15% were ESBL-positive. Compared to nurses from Hospital 3, nurses from Hospital 1 were 59% less likely to be colonized, while nurses from Hospital 2 were 62% more likely to be colonized.

Conclusion

In hospitals where CP is in place for ESBL-positive patients, ESBL-PE prevalence in nursing staff was significantly lower. Additionally, a work experience of two to four years increased the odds of ESBL-PE colonization in comparison with longer nursing experience. CP may be a justifiable means of protection against ESBL-PE transmission to healthy nurses. The risk factors for colonization were discontinuation of CP and a shorter clinical work experience.

Impact of an Antibiotic Stewardship Program on the Incidence of Resistant Escherichia coli: A Quasi-Experimental Study

Infections caused by multidrug-resistant Gram-negative bacteria increase hospitalizations and mortality rates; antibiotic pressure increases resistance rates. We evaluated the impact of the antibiotics stewardship program (ASP) on Escherichia coli resistance rates, evaluating all antibiotic use and patients with positive cultures hospitalized between 2011 and 2018. Data on antibiotics were collected quarterly as the defined daily dose (DDD)/100 days hospitalization. In 2014, an intervention was introduced, targeting the reduction of overall antibiotic use as well as specifically targeting quinolones and other broad-spectrum antibiotics. Using interrupted time series analysis (ITS), we compared the rates and trends of antibiotic use and resistant E. coli. We included 6001 patients, 3182 pre-ASP and 2819 post-ASP. We observed significant changes in absolute numbers as well as in trends for use of DDD/100 days of all antibiotics by 31% from 76 to 52, and by 52% from 10.4 to 4.9 for quinolones. ITS demonstrated that before the ASP intervention, there was a slope pattern for increased E. coli resistance to antibiotics. This slope was reversed following the intervention for quinolones −1.52, aminoglycosides −2.04, and amoxicillin clavulanate (amox/clav) −1.76; the effect of the intervention was observed as early as three months after the intervention and continued to decrease over time until the end of the study, at 48 months. We conclude that the ASP can positively impact the resistance rate of Gram-negative infections over time, regardless of the targeted combination of antibiotics, if the overall use is reduced.

Development and validation of a time and motion guide to assess the costs of prevention and control interventions for nosocomial infections: A Delphi method among experts

BACKGROUND

Nosocomial infections place a heavy burden on patients and healthcare providers and impact health care institutions financially. Reducing nosocomial infections requires an integrated program of prevention and control using key clinical best care practices. No instrument currently exists that measures these practices in terms of personnel time and material costs.

OBJECTIVE

To develop and validate an instrument that would measure nosocomial infection control and prevention best care practice costs, including estimates of human and material resources.

METHODS

An evaluation of the literature identified four practices essential for the control of pathogens: hand hygiene, hygiene and sanitation, screening and additional precaution. To reflect time, materials and products used in these practices, our team developed a time and motion guide. Iterations of the guide were assessed in a Delphi technique; content validity was established using the content validity index and reliability was assessed using Kruskall Wallis one-way ANOVA of rank test.

RESULTS

Two rounds of Delphi review were required; 88% of invited experts completed the assessment. The final version of the guide contains eight dimensions: Identification [83 items]; Personnel [5 items]; Additional Precautions [1 item]; Hand Hygiene [2 items]; Personal Protective Equipment [14 items]; Screening [4 items]; Cleaning and Disinfection of Patient Care Equipment [33 items]; and Hygiene and Sanitation [24 items]. The content validity index obtained for all dimensions was acceptable (> 80%). Experts statistically agreed on six of the eight dimensions.

DISCUSSION/CONCLUSION

This study developed and validated a new instrument based on expert opinion, the time and motion guide, for the systematic assessment of costs relating to the human and material resources used in nosocomial infection prevention and control. This guide will prove useful to measure the intensity of the application of prevention and control measures taken before, during and after outbreak periods or during pandemics such as COVID-19.

Is systematic fecal carriage screening of extended-spectrum beta-lactamase-producing Enterobacteriaceae still useful in intensive care unit: a systematic review

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are disseminating worldwide leading to increased hospital length of stay and mortality in intensive care units (ICU). ESBL-E dissemination was first due to outbreaks in hospital settings which led to the implementation of systematic fecal carriage screening to improve hygiene procedures by contact precautions. ESBLs have since spread in the community, and the relevance of contact precautions is questioned. ESBL-E dissemination led to an overuse of carbapenems triggering the emergence of carbapenem-resistant Enterobacteriaceae. Empirical antimicrobial therapy based on ESBL-E fecal carriage has been proposed but is debated as it could increase the consumption of carbapenems among ESBL-E carriers without any clinical benefit. Finally, selective decontamination among ESBL-E fecal carriers is evoked to decrease the risk for subsequent ESBL-E infection, but its efficacy remains debated. We propose to systematically review the evidence to recommend or not such systematic ESBL-E fecal carriage screening in adult ICU.

METHODS

Every article focusing on ESBL-E and ICU available on the MEDLINE database was assessed. Articles were included if focusing on cross-transmission, efficacy of hygiene procedures, link between ESBL-E colonization and infection or guidance of empirical therapy or selective decontamination efficacy.

RESULTS

Among 330 articles referenced on PubMed, 39 abstracts were selected for full-text assessment and 25 studies were included. Systematic screening of ESBL-E fecal carriage to guide contact precautions do not seem to decrease the rate of ESBL-E cross-transmission. It has a very good negative predictive value for subsequent ESBL-E infections but a positive predictive value between 40 and 50% and so does not help to spare carbapenems. Cessation of ESBL-E carriage systematic screening could decrease the use of carbapenems in ICU without any clinical harm. Nevertheless, further studies are needed to validate these results from monocentric before-after study. Selective decontamination strategy applied to ESBL-E fecal carriers could be helpful, but available data are conflicting.

CONCLUSION

Current knowledge lacks of high-quality evidence to strongly recommend in favor of or against a systematic ESBL-E fecal carriage screening policy for ICU patients in a non-outbreak situation. Further evaluation of selective decontamination or fecal microbiota transplantation among ESBL-E fecal carriers is needed.

Prevention and Control of Multidrug-Resistant Gram-Negative Bacteria in Adult Intensive Care Units: A Systematic Review and Network Meta-analysis

Background

This study evaluated the relative efficacy of strategies for the prevention of multidrug-resistant gram-negative bacteria (MDR-GNB) in adult intensive care units (ICUs).

Methods

A systematic review and network meta-analysis was performed; searches of the Cochrane Library, PubMed, Embase, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) included all randomized controlled trials and observational studies conducted in adult patients hospitalized in ICUs and evaluating standard care (STD), antimicrobial stewardship program (ASP), environmental cleaning (ENV), decolonization methods (DCL), or source control (SCT), simultaneously. The primary outcomes were MDR-GNB acquisition, colonization, and infection; secondary outcome was ICU mortality.

Results

Of 3805 publications retrieved, 42 met inclusion criteria (5 randomized controlled trials and 37 observational studies), involving 62068 patients (median age, 58.8 years; median APACHE [Acute Physiology and Chronic Health Evaluation] II score, 18.9). The majority of studies reported extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and MDR Acinetobacter baumannii. Compared with STD, a 4-component strategy composed of STD, ASP, ENV, and SCT was the most effective intervention (rate ratio [RR], 0.05 [95% confidence interval {CI}, .01-.38]). When ENV was added to STD+ASP or SCT was added to STD+ENV, there was a significant reduction in the acquisition of MDR A. baumannii (RR, 0.28 [95% CI, .18-.43] and 0.48 [95% CI, .35-.66], respectively). Strategies with ASP as a core component showed a statistically significant reduction the acquisition of ESBL-producing Enterobacteriaceae (RR, 0.28 [95% CI, .11-.69] for STD+ASP+ENV and 0.23 [95% CI, .07-.80] for STD+ASP+DCL).

Conclusions

A 4-component strategy was the most effective intervention to prevent MDR-GNB acquisition. As some strategies were differential for certain bacteria, our study highlighted the need for further evaluation of the most effective prevention strategies.

Counting the cost of an outbreak of carbapenemase-producing Enterobacteriaceae: an economic evaluation from a hospital perspective

OBJECTIVE

To perform an economic evaluation on the cost associated with an outbreak of carbapenemase-producing Enterobacteriaceae (CPE).

METHODS

We performed an observational economic evaluation of an outbreak of CPE (NDM-producing Klebsiella pneumoniae) affecting 40 patients in a group of five hospitals across three sites in West London. Costs were split into actual expenditure (including anti-infective costs, enhanced CPE screening, contact precautions, temporary ward-based monitors of hand and environmental practice, and environmental decontamination), and 'opportunity cost' (staff time, bed closures and elective surgical missed revenue). Costs are estimated from the hospital perspective over the 10-month duration of the outbreak.

RESULTS

The outbreak cost €1.1m over 10 months (range €0.9-1.4m), comprising €312 000 actual expenditure, and €822 000 (range €631 000-€1.1m) in opportunity cost. An additional €153 000 was spent on Estates renovations prompted by the outbreak. Actual expenditure comprised: €54 000 on anti-infectives for 18 patients treated, €94 000 on laboratory costs for screening, €73 000 on contact precautions for 1831 contact precautions patient-days, €42 000 for hydrogen peroxide vapour decontamination of 24 single rooms, €43 000 on 2592 hours of ward-based monitors, and €6000 of expenditure related to ward and bay closures. Opportunity costs comprised: €244 000 related to 1206 lost bed-days (range 366-2562 bed-days, €77 000-€512 000), €349 000 in missed revenue from 72 elective surgical procedures, and €228 000 in staff time (range €205 000-€251 000). Reduced capacity to perform elective surgical procedures related to bed closures (€349 000) represented the greatest cost.

CONCLUSIONS

The cost estimates that we present suggest that CPE outbreaks are highly costly.

Extended-spectrum beta-lactamase--producing enterobacteriaceae in the intensive care unit: acquisition does not mean cross-transmission

Background

In intensive care unit (ICU), infection and colonization by resistant Gram-negative bacteria increase costs, length of stay and mortality. Extended-spectrum beta-lactamase − producing Enterobacteriaceae (ESBL-E) is a group of pathogens increasingly encountered in ICU setting. Conditions that promote ESBL-E acquisition are not completely understood. The increasing incidence of infections related to ESBL-E and the unsolved issues related to ESBL-E cross-transmission, prompted us to assess the rates of referred and acquired cases of ESBL-E in ICU and to assess patient-to-patient cross-transmission of ESBL-E using a multimodal microbiological analysis.

Methods

During a 5-month period, all patients admitted to a medical ICU were tested for ESBL-E carriage. A rectal swab was performed at admission and then twice a week until discharge or death. ESBL-E strains were analyzed according to antibiotic susceptibility pattern, rep-PCR (repetitive-element Polymerase chain reaction) chromosomal analysis, and plasmid PCR (Polymerase chain reaction) analysis of ESBL genes. Patient-to-patient transmission was deemed likely when 2 identical strains were found in 2 patients hospitalized simultaneously in the ICU.

Results

Among the 309 patients assessed for ESBL-E carriage on admission, 25 were found to carry ESBL-E (importation rate: 8 %). During follow-up, acquisition was observed among 19 of them (acquisition rate: 6.5 %). Using the multimodal microbiological approach, we found only one case of likely patient-to-patient ESBL-E transmission.

Conclusions

In unselected ICU patients, we found rather low rates of ESBL-E referred and acquired cases. Only 5 % of acquisitions appeared to be related to patient-to-patient transmission. These data highlight the importance of jointly analyzing phenotypic profile and molecular data to discriminate strains of ESBL-E.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1489-z) contains supplementary material, which is available to authorized users.

Impact of infection with extended-spectrum β-lactamase-producing Escherichia coli or Klebsiella species on outcome and hospitalization costs

BACKGROUND

Extended-spectrum β-lactamase (ESBL)-producing bacteria are important sources of infection; however, Canadian data evaluating the impact of ESBL-associated infection are lacking.

AIM

To determine whether patients infected with ESBL-producing Escherichia coli or Klebsiella species (ESBL-EcKs) exhibit differences in clinical outcome, microbiological outcome, mortality, and/or hospital resource use compared to patients infected with non-ESBL-producing strains.

METHODS

A retrospective case-control study of 75 case patients with ESBL-EcKs matched to controls infected with non-ESBL-EcKs who were hospitalized from June 2010 to April 2013 was conducted. Patient-level cost data were provided by the institution's business office. Clinical data were collected using the electronic databases and paper charts.

FINDINGS

Median infection-related hospitalization costs per patient were greater for cases than controls (C$10,507 vs C$7,882; median difference: C$3,416; P = 0.04). The primary driver of increased costs was prolonged infection-related hospital length of stay (8 vs 6 days; P = 0.02) with patient location (ward, ICU) and indirect care costs (including costs associated with infection prevention and control) as the leading cost categories. Cases were more likely to experience clinical failure (25% vs 11%; P = 0.03), with a higher all-cause mortality (17% vs 5%; P = 0.04). Less than half of case patients were prescribed appropriate empiric antimicrobial therapy, whereas controls received adequate initial treatment in nearly all circumstances (48% vs 96%; P < 0.01).

CONCLUSION

Patients with infection caused by ESBL-EcKs are at increased risk for clinical failure and mortality, with additional cost to the Canadian healthcare system of C$3,416 per patient.

Controversies in guidelines for the control of multidrug-resistant Gram-negative bacteria in EU countries

The various guidelines that are available for multidrug-resistant Gram-negative bacteria are useful, and contain broad areas of agreement. However, there are also important areas of controversy between the guidelines in terms of the details of applying contact precautions, single-room isolation and active surveillance cultures, differences in the approach to environmental cleaning and disinfection, and whether or not to perform staff and patient cohorting, healthcare worker screening or patient decolonization. The evidence-base is extremely limited and further research is urgently required to inform an evidence-based approach to multidrug-resistant Gram-negative bacteria prevention and control.

Targeted screening for third-generation cephalosporin-resistant Enterobacteriaceae carriage among patients admitted to intensive care units: a quasi-experimental study

Introduction

Identification of third-generation, cephalosporin-resistant Enterobacteriaceae (3GC-RE) carriers by rectal screening at admission seems to be an important step in the prevention of transmission and outbreaks; however, little is known about its effectiveness. The aim of this study was to evaluate the impact of ‘targeted screening’ at patient admission to intensive care units (ICUs) on the incidence of 3GC-RE hospital-acquired infections (HAIs) and compare it to ‘universal screening’.

Methods

We undertook a quasi-experimental study of two ICUs (unit A: intervention group; unit B: control group) at a university-affiliated hospital between 1 January 2008 and 31 December 2011. In unit A, patients were screened universally for 3GC-RE at admission during period 1 (1 January 2008 through 30 September 2010). During period 2 (2011 calendar year), the intervention was implemented in unit A; patients transferred from another unit or hospital were screened selectively. In unit B, all patients were screened throughout periods 1 and 2. 3GC-RE-related HAI incidence rates were expressed per 1,000 patient-days. Incidence rate ratios (IRRs) were examined by multivariate Poisson regression modelling.

Results

In unit A, 3GC-RE-related HAI incidence rates decreased from 5.4 (95% confidence interval (CI), 4.1 to 7.0) during period 1 to 1.3 (95% CI, 0.5 to 2.9) during period 2 (P < 0.001). No changes were observed in unit B between periods 1 and 2 (P = 0.5). In unit A, the adjusted incidence of 3GC-RE-related HAIs decreased in period 2 compared with period 1 (adjusted IRR, 0.3; 95% CI, 0.1 to 0.9; P = 0.03) independently of temporal trend, trauma and age. No changes were seen in unit B (P = 0.4). The total number of rectal swabs taken showed an 85% decrease in unit A between period 1 and 2 (P < 0.001).

Conclusions

Targeted screening of 3GC-RE carriers at ICU admission was not associated with an increase in 3GC-RE-related HAI incidence compared with universal screening. Total number of rectal swabs decreased significantly. These findings suggest that targeted screening may be worth assessing as an alternative to universal screening.

Are strict isolation policies based on susceptibility testing actually effective in the prevention of the nosocomial spread of multi-drug-resistant gram-negative rods?

BACKGROUND

The emergence of multi-drug-resistant gram-negative rods (MDR-GNRs) has become a worldwide problem. To limit the emergence of MDR-GNRs, a tertiary care cancer center in Japan implemented a policy that requires the pre-emptive isolation of patients with organisms that have the potential to be MDR-GNRs.

METHODS

A retrospective analysis was performed. Any gram-negative bacillus isolates categorized as intermediate or resistant to at least 2 classes of antimicrobials were subjected to contact precautions. The incidence of patients with MDR-GNRs was analyzed.

RESULTS

There was no difference between the preintervention and intervention time periods in the detection rate of nonfermenting MDR-GNR species (0.15 per 10,000 vs 0.35 per 10,000 patient-days, P = .08). There was an increase in the detection rate of multi-drug-resistant Enterobacteriaceae (0.19 per 10,000 vs 0.56 per 10,000 patient-days, P = .007), which was prominent for extended-spectrum β-lactamase (ESBL)-producing organisms (0.19 per 10,000 vs 0.50 per 10,000 patient-days, P = .02).

CONCLUSIONS

Our intervention kept the emergence of multi-drug-resistant non-glucose-fermenting gram-negative bacilli to a small number, but it failed to prevent an increase in ESBL producers. Policies, such as active detection and isolation, are warranted to decrease the incidence of these bacilli.

Natural history of colonization with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE): a systematic review

Background

No published systematic reviews have assessed the natural history of colonization with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE). Time to clearance of colonization has important implications for patient care and infection control policy.

Methods

We performed parallel searches in OVID Medline for studies that reported the time to documented clearance of MRSA and VRE colonization in the absence of treatment, published between January 1990 and July 2012.

Results

For MRSA, we screened 982 articles, identified 16 eligible studies (13 observational studies and 3 randomized controlled trials), for a total of 1,804 non-duplicated subjects. For VRE, we screened 284 articles, identified 13 eligible studies (12 observational studies and 1 randomized controlled trial), for a total of 1,936 non-duplicated subjects. Studies reported varying definitions of clearance of colonization; no study reported time of initial colonization. Studies varied in the frequency of sampling, assays used for sampling, and follow-up period. The median duration of total follow-up was 38 weeks for MRSA and 25 weeks for VRE. Based on pooled analyses, the model-estimated median time to clearance was 88 weeks after documented colonization for MRSA-colonized patients and 26 weeks for VRE-colonized patients. In a secondary analysis, clearance rates for MRSA and VRE were compared by restricting the duration of follow-up for the MRSA studies to the maximum observed time point for VRE studies (43 weeks). With this restriction, the model-fitted median time to documented clearance for MRSA would occur at 41 weeks after documented colonization, demonstrating the sensitivity of the pooled estimate to length of study follow-up.

Conclusions

Few available studies report the natural history of MRSA and VRE colonization. Lack of a consistent definition of clearance, uncertainty regarding the time of initial colonization, variation in frequency of sampling for persistent colonization, assays employed and variation in duration of follow-up are limitations of the existing published literature. The heterogeneity of study characteristics limits interpretation of pooled estimates of time to clearance, however, studies included in this review suggest an increase in documented clearance over time, a result which is sensitive to duration of follow-up.

Trends in human fecal carriage of extended-spectrum β-lactamases in the community: toward the globalization of CTX-M

In the last 10 years, extended-spectrum β-lactamase-producing enterobacteria (ESBL-E) have become one of the main challenges for antibiotic treatment of enterobacterial infections, largely because of the current CTX-M enzyme pandemic. However, most studies have focused on hospitalized patients, though today it appears that the community is strongly affected as well. We therefore decided to devote our investigation to trends in ESBL-E fecal carriage rates and comprehensively reviewed data from studies conducted on healthy populations in various parts of the world. We show that (i) community ESBL-E fecal carriage, which was unknown before the turn of the millennium, has since increased significantly everywhere, with developing countries being the most affected; (ii) intercontinental travel may have emphasized and globalized the issue; and (iii) CTX-M enzymes, especially CTX-M-15, are the dominant type of ESBL. Altogether, these results suggest that CTX-M carriage is evolving toward a global pandemic but is still insufficiently described. Only a better knowledge of its dynamics and biology will lead to further development of appropriate control measures.

The effect of a hospital-wide urine culture screening intervention on the incidence of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella species

OBJECTIVE

Optimal strategies for limiting the transmission of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella spp (ESBL-EK) in the hospital setting remain unclear. The objective of this study was to evaluate the impact of a urine culture screening strategy on the incidence of ESBL-EK.

DESIGN

Prospective quasi-experimental study.

SETTING

Two intervention hospitals and one control hospital within a university health system from 2005 to 2009.

PATIENTS AND INTERVENTION

All clinical urine cultures with E. coli or Klebsiella spp were screened for ESBL-EK. Patients determined to be colonized or infected with ESBL-EK were placed in a private room with contact precautions. The primary outcome of interest was nosocomial ESBL-EK incidence in nonurinary clinical cultures (cases occurring more than 48 hours after admission). Changes in monthly ESBL-EK incidence rates were evaluated with mixed-effects Poisson regression models, with adjustment for institution-level characteristics (eg, total admissions).

RESULTS

The overall incidence of ESBL-EK increased from 1.42/10,000 patient-days to 2.16/10,000 patient-days during the study period. The incidence of community-acquired ESBL-EK increased nearly 3-fold, from 0.33/10,000 patient-days to 0.92/10,000 patient-days (P < .001). On multivariable analysis, the intervention was not significantly associated with a reduction in nosocomial ESBL-EK incidence (incidence rate ratio, 1.38 [95% confidence interval, 0.83-2.31]; P - .21).

CONCLUSIONS

Universal screening of clinical urine cultures for ESBL-EK did not result in a reduction in nosocomial ESBL-EK incidence rates, most likely because of increases in importation of ESBL-EK cases from the community. Further studies are needed on elucidating optimal infection control interventions to limit spread of ESBL-producing organisms in the hospital setting.

[Impact of enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBLE) incidence increasing on barrier precautions implementation in a university hospital]

AIM OF THE STUDY

The French national surveillance program of multidrug-resistant bacteria (MDR) shows an increase of enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBLE) incidence. The objectives of this study were to assess: the incidence of EBLSE in a large French university hospital between 2005 and 2010, and the difference of barrier precautions implementation between ESBL and other MDR.

METHODS

The ESBLE incidence measure used data from the laboratory of bacteriology. The application of isolation and barrier precautions was analyzed from the MRB national surveillance data over a 3-year period from 2006 to 2008. Data were entered and analyzed using Epi Info software. The Chi(2) test was used for the comparison of proportions.

RESULTS

The overall incidence of ESBLE was significantly higher in 2010 than in 2005 (0.20/1000 patients-days vs 0.03/1000 patients-days, respectively) (P<0.001). The same was observed for Escherichia coli incidence with rates ranging from 0.02/1000 patients-days in 2005 to 0.15/1000 patients-days in 2010. Isolation precautions for patients with EBLSE were applied in relation for most patients with MRB (ESBLE vs others), without significant difference.

CONCLUSION

The surveillance programme of MRB showed a significant increase of ESBLE, especially for E. coli. Isolation and barrier precautions were used for most patients with MRB, including ESBLE.

Limits of patient isolation measures to control extended-spectrum beta-lactamase-producing Enterobacteriaceae: model-based analysis of clinical data in a pediatric ward

Background

Extended-spectrum beta-lactamase–producing Enterobacteriaceae (ESBL-E) are a growing concern in hospitals and the community. How to control the nosocomial ESBL-E transmission is a matter of debate. Contact isolation of patients has been recommended but evidence supporting it in non-outbreak settings has been inconclusive.

Methods

We used stochastic transmission models to analyze retrospective observational data from a two-phase intervention in a pediatric ward, successively implementing single-room isolation and patient cohorting in an isolation ward, combined with active ESBL-E screening.

Results

For both periods, model estimates suggested reduced transmission from isolated/cohorted patients. However, most of the incidence originated from sporadic sources (i.e. independent of cross-transmission), unaffected by the isolation measures. When sporadic sources are high, our model predicted that even substantial efforts to prevent transmission from carriers would have limited impact on ESBL-E rates.

Conclusions

Our results provide evidence that, considering the importance of sporadic acquisition, e.g. endogenous selection of resistant strains following antibiotic treatment, contact-isolation measures alone might not suffice to control ESBL-E. They also support the view that estimating cross-transmission extent is key to predicting the relative success of contact-isolation measures. Mathematical models could prove useful for those estimations and guide decisions concerning the most effective control strategy.

Modern trends in infection control practices in intensive care units

Hospital-acquired infections (HAIs) are common in intensive care unit (ICU) patients and are associated with increased morbidity and mortality. There has been an increasing effort to prevent HAIs, and infection control practices are paramount in avoiding these complications. In the last several years, numerous developments have been seen in the infection prevention strategies in various health care settings. This article reviews the modern trends in infection control practices to prevent HAIs in ICUs with a focus on methods for monitoring hand hygiene, updates in isolation precautions, new methods for environmental cleaning, antimicrobial bathing, prevention of ventilator-associated pneumonia, central line-associated bloodstream infections, catheter-associated urinary tract infections, and Clostridium difficile infection.

Influence of clinical breakpoint changes from CLSI 2009 to EUCAST 2011 antimicrobial susceptibility testing guidelines on multidrug resistance rates of Gram-negative rods

Multidrug resistance (MDR) rates of Gram-negative rods were analyzed comparing CLSI 2009 and EUCAST 2011 antibiotic susceptibility testing guidelines. After EUCAST 2011 was applied, the MDR rates increased for Klebsiella pneumoniae (2.2%), Enterobacter cloacae (1.1%), Pseudomonas aeruginosa (0.7%), and Escherichia coli (0.4%). A total of 24% of Enterobacteriaceae MDR isolates and 12% of P. aeruginosa MDR isolates were categorized as MDR due to breakpoint changes.

A regional informatics platform for coordinated antibiotic-resistant infection tracking, alerting, and prevention

BACKGROUND

We developed and assessed the impact of a patient registry and electronic admission notification system relating to regional antimicrobial resistance (AMR) on regional AMR infection rates over time. We conducted an observational cohort study of all patients identified as infected or colonized with methicillin-resistant Staphylococcus aureus (MRSA) and/or vancomycin-resistant enterococci (VRE) on at least 1 occasion by any of 5 healthcare systems between 2003 and 2010. The 5 healthcare systems included 17 hospitals and associated clinics in the Indianapolis, Indiana, region.

METHODS

We developed and standardized a registry of MRSA and VRE patients and created Web forms that infection preventionists (IPs) used to maintain the lists. We sent e-mail alerts to IPs whenever a patient previously infected or colonized with MRSA or VRE registered for admission to a study hospital from June 2007 through June 2010.

RESULTS

Over a 3-year period, we delivered 12 748 e-mail alerts on 6270 unique patients to 24 IPs covering 17 hospitals. One in 5 (22%-23%) of all admission alerts was based on data from a healthcare system that was different from the admitting hospital; a few hospitals accounted for most of this crossover among facilities and systems.

CONCLUSIONS

Regional patient registries identify an important patient cohort with relevant prior antibiotic-resistant infection data from different healthcare institutions. Regional registries can identify trends and interinstitutional movement not otherwise apparent from single institution data. Importantly, electronic alerts can notify of the need to isolate early and to institute other measures to prevent transmission.

Disparity in infection control practices for multidrug-resistant Enterobacteriaceae

BACKGROUND

There is a lack of empiric evidence regarding the optimal approach to controlling the transmission of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenem-resistant Enterobacteriaceae (CRE). In this context, we expect that infection control practices for these organisms vary widely between hospitals.

METHODS

A survey examining infection control practices for ESBL-E and CRE was distributed to 6 academic and 9 community hospitals in Toronto, Canada.

RESULTS

All hospitals responded to the survey. Among 15 hospitals in 1 geographic area, 8 different approaches to the management of ESBL-E were utilized. There was wide variation in the use infection control practices including admission screening (53% and 53%), contact precautions (53% and 100%), and isolation (60% and 100%) for ESBL-E and CRE, respectively. Of hospitals performing admission screening, 75% used risk factor-based screening for ESBL-E and CRE.

CONCLUSION

Even within a single geographic area, there is wide variation in infection control strategies to contain or control ESBL-E and CRE. These results are concerning given evidence that a coordinated approach may be required to prevent or limit the emergence of CRE.

Mathematical model of the impact of a nonantibiotic treatment for Clostridium difficile on the endemic prevalence of vancomycin-resistant enterococci in a hospital setting

Introduction. Clostridium difficile-associated disease (CDAD) is treated using antibiotics, which often leads to the emergence of antibiotic-resistant bacteria such as vancomycin-resistant enterococci (VRE). This study estimated the impact of a non antibiotic treatment for CDAD on VRE prevalence. Methods. A previously published model describing the impact of in-hospital antibiotic use on VRE prevalence was adapted to include CDAD treatment. Simulations compared the prevalence of VRE when nonantibiotic versus antibiotic therapy was used. Results. Nonantibiotic treatment in 50% of CDAD patients resulted in an 18% relative reduction in the prevalence of VRE colonization compared with antibiotic use only. Sensitivity analysis found the model to be most sensitive to rates of antibiotic initiation and discontinuation, prevalence of VRE in admitted patients, length of stay of colonized patients, probability of CDAD acquisition, and hand-washing compliance. Conclusion. Nonantibiotic treatment of patients hospitalized with CDAD may significantly reduce the incidence of VRE colonization.

Preventing the spread of multidrug-resistant gram-negative pathogens: recommendations of an expert panel of the German Society For Hygiene and Microbiology

BACKGROUND

Infections with multidrug-resistant gram-negative bacteria are hard to treat and cause high morbidity and mortality. The direct transmission of such pathogens is well documented, and measures to protect other patients would seem indicated. Nonetheless, evidence-based recommendations are not yet available because of insufficient data from clinical trials.

METHODS

An expert panel was convened by two sections of the German Society for Hygiene and Microbiology (the permanent committee on general and hospital hygiene and the special committee on infection prevention and antibiotic resistance in hospitals) to review existing data on the epidemiology and diagnostic evaluation of multidrug-resistant gram-negative pathogens. The panel carried out a selective review of the relevant literature, with special attention to national guidelines.

RESULTS AND CONCLUSION

In this paper, the expert panel presents a definition of multidrug-resistant gram-negative pathogens and recommends measures for presenting the spread of infection from colonized and infected patients in non-outbreak situations. These measures depend on the risk profile of the clinical setting. They are mostly to be considered "expert opinion," rather than "evidence-based."

Documentation of contact precautions in an electronic health record

Contact precautions are implemented to reduce transmission of multidrug-resistant organisms but may also increase hospital costs and patient complications. The goal of this study was to determine the prevalence of documentation of contact precautions (provider orders and nursing flowsheet documentation) in an electronic health record. Orders and nursing documentation were simultaneously present for only 42.3% of patient rooms with contact precaution signs, and 17.8% of rooms with signs had neither orders nor nursing documentation.

The efficacy of infection control interventions in reducing the incidence of extended-spectrum β-lactamase-producing Enterobacteriaceae in the nonoutbreak setting: A systematic review

We conducted a systematic review to examine the efficacy of infection control interventions for the control of ESBL-producing Enterobacteriaceae in hospitals in the non-outbreak setting. Although 4 uncontrolled, retrospective studies were included in the review, no well designed prospective studies capable of informing infection control practice were identified, underscoring the urgent need for research in this area.

Isolation prioritization tool: revision, adaptation and application

The provision of single rooms for the care of patients who require isolation may not match the number required. Placing patients in isolation facilities may have an effect on their psychological wellbeing and the quality of care delivered. To ensure a rational and consistent approach to the prioritization of single room usage, an existing prioritization system was revised. This was validated by a group of experts and tested in an acute hospital. A simple short cut guide was developed and used.

Modelling the costs and effects of selective and universal hospital admission screening for methicillin-resistant Staphylococcus aureus

Background

Screening at hospital admission for carriage of methicillin-resistant Staphylococcus aureus (MRSA) has been proposed as a strategy to reduce nosocomial infections. The objective of this study was to determine the long-term costs and health benefits of selective and universal screening for MRSA at hospital admission, using both PCR-based and chromogenic media-based tests in various settings.

Methodology/Principal Findings

A simulation model of MRSA transmission was used to determine costs and effects over 15 years from a US healthcare perspective. We compared admission screening together with isolation of identified carriers against a baseline policy without screening or isolation. Strategies included selective screening of high risk patients or universal admission screening, with PCR-based or chromogenic media-based tests, in medium (5%) or high nosocomial prevalence (15%) settings. The costs of screening and isolation per averted MRSA infection were lowest using selective chromogenic-based screening in high and medium prevalence settings, at $4,100 and $10,300, respectively. Replacing the chromogenic-based test with a PCR-based test costs $13,000 and $36,200 per additional infection averted, and subsequent extension to universal screening with PCR would cost $131,000 and $232,700 per additional infection averted, in high and medium prevalence settings respectively. Assuming $17,645 benefit per infection averted, the most cost-saving strategies in high and medium prevalence settings were selective screening with PCR and selective screening with chromogenic, respectively.

Conclusions/Significance

Admission screening costs $4,100–$21,200 per infection averted, depending on strategy and setting. Including financial benefits from averted infections, screening could well be cost saving.

Isolation precautions for antibiotic-resistant bacteria in healthcare settings

PURPOSE OF REVIEW

Emergence of drug-resistant bacteria and new or changing infectious pathogens is an important public health problem. Transmission of these pathogens in an acute care setting may occur frequently if proper precautions are not taken. Despite several guidelines and an abundance of literature on the prevention of transmission of epidemiologically important organisms in the healthcare setting, substantial controversy exists. This review focuses on recent data regarding the use of infection control and isolation precautions.

RECENT FINDINGS

New data are available, but the conflict surrounding the use of active surveillance of methicillin-resistant Staphylococcus aureus (MRSA) has not been resolved. The emergence of multidrug-resistant Gram-negative bacteria has prompted a greater interest in infection control strategies for prevention of their spread. Outbreaks of Clostridium difficile have responded to broad infection control initiatives, but further research is required to determine whether the best infection control precautions are being utilized.

SUMMARY

Effective prevention of the transmission of pathogens within the healthcare system requires a multifaceted approach. Existing guidelines should be used to create institutional policies specific to individual patient populations, problem pathogens and the ability to practically implement various infection control procedures. Despite ongoing study, the use of active surveillance to prevent transmission of MRSA continues to be a complex, controversial and challenging issue.

Screening and isolation for infection control

Control measures aimed to reduce the prevalence of healthcare-associated infections include active surveillance cultures (ASCs), contact isolation of patients colonised with epidemiologically significant pathogens, and pre-emptive isolation of high risk patients. However, the benefits of these measures are questionable. A systematic review of isolation policies demonstrated that intensive concerted interventions including isolation can substantially reduce nosocomial meticillin-resistant Staphylococcus aureus (MRSA) infection. Monitoring of interventions is fundamental. Surveillance data should be presented and fed back appropriately. International guidelines suggest that only intensive care units should apply extensive ASCs. However, legislation for mandatory screening at hospital admission has been advocated in many countries. Targeted screening could be used to limit the potential for dissemination of antibiotic-resistant pathogens from otherwise unsuspected carriers from the start of patients' hospitalisation, as opposed to other strategies, in which screening programmes target patients already hospitalised. Although the influx of antibiotic-resistant pathogens into the hospital would not change, early detection would reduce the time colonised patients might have to disseminate pathogens. Recently, rapid methods for molecular detection of MRSA have been developed. Data on the impact of these tests on the MRSA acquisition rate are extremely heterogeneous. Published studies differ according to the settings in which they have been evaluated, the choice of patient population to be screened, other infection control measures employed and, most importantly, study design and baseline prevalence of MRSA. Based on these studies, definitive recommendations cannot be made.