Topical antimicrobials in combination with admission screening and barrier precautions to control endemic methicillin-resistant Staphylococcus aureus in an Intensive Care Unit

The impact of chlorhexidine bathing on hospital-acquired bloodstream infections: a systematic review and meta-analysis

Background

Chlorhexidine gluconate (CHG) bathing of hospitalized patients may have benefit in reducing hospital-acquired bloodstream infections (HABSIs). However, the magnitude of effect, implementation fidelity, and patient-centered outcomes are unclear. In this meta-analysis, we examined the effect of CHG bathing on prevention of HABSIs and assessed fidelity to implementation of this behavioral intervention.

Methods

We undertook a meta-analysis by searching Medline, EMBASE, CINAHL, Scopus, and Cochrane’s CENTRAL registry from database inception through January 4, 2019 without language restrictions. We included randomized controlled trials, cluster randomized trials and quasi-experimental studies that evaluated the effect of CHG bathing versus a non-CHG comparator for prevention of HABSIs in any adult healthcare setting. Studies of pediatric patients, of pre-surgical CHG use, or without a non-CHG comparison arm were excluded. Outcomes of this study were HABSIs, patient-centered outcomes, such as patient comfort during the bath, and implementation fidelity assessed through five elements: adherence, exposure or dose, quality of the delivery, participant responsiveness, and program differentiation. Three authors independently extracted data and assessed study quality; a random-effects model was used.

Results

We included 26 studies with 861,546 patient-days and 5259 HABSIs. CHG bathing markedly reduced the risk of HABSIs (IRR = 0.59, 95% confidence interval [CI]: 0.52–0.68). The effect of CHG bathing was consistent within subgroups: randomized (0.67, 95% CI: 0.53–0.85) vs. non-randomized studies (0.54, 95% CI: 0.44–0.65), bundled (0.66, 95% CI: 0.62–0.70) vs. non-bundled interventions (0.51, 95% CI: 0.39–0.68), CHG impregnated wipes (0.63, 95% CI: 0.55–0.73) vs. CHG solution (0.41, 95% CI: 0.26–0.64), and intensive care unit (ICU) (0.58, 95% CI: 0.49–0.68) vs. non-ICU settings (0.56, 95% CI: 0.38–0.83). Only three studies reported all five measures of fidelity, and ten studies did not report any patient-centered outcomes.

Conclusions

Patient bathing with CHG significantly reduced the incidence of HABSIs in both ICU and non-ICU settings. Many studies did not report fidelity to the intervention or patient-centered outcomes. For sustainability and replicability essential for effective implementation, fidelity assessment that goes beyond whether a patient received an intervention or not should be standard practice particularly for complex behavioral interventions such as CHG bathing.

Trial registration

Study registration with PROSPERO CRD42015032523.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4002-7) contains supplementary material, which is available to authorized users.

Effectiveness of daily chlorhexidine bathing for reducing gram-negative infections: A meta-analysis

OBJECTIVE

Multiple studies have demonstrated that daily chlorhexidine gluconate (CHG) bathing is associated with a significant reduction in infections caused by gram-positive pathogens. However, there are limited data on the effectiveness of daily CHG bathing on gram-negative infections. The aim of this study was to determine whether daily CHG bathing is effective in reducing the rate of gram-negative infections in adult intensive care unit (ICU) patients.

DESIGN

We searched MEDLINE and 3 other databases for original studies comparing daily bathing with and without CHG. Two investigators extracted data independently on baseline characteristics, study design, form and concentration of CHG, incidence, and outcomes related to gram-negative infections. Data were combined using a random-effects model and pooled relative risk ratios (RRs), and 95% confidence intervals (CIs) were derived.

RESULTS

In total, 15 studies (n = 34,895 patients) met inclusion criteria. Daily CHG bathing was not significantly associated with a lower risk of gram-negative infections compared with controls (RR, 0.89; 95% CI, 0.73-1.08; P = .24). Subgroup analysis demonstrated that daily CHG bathing was not effective for reducing the risk of gram-negative infections caused by Acinetobacter, Escherichia coli, Klebsiella, Enterobacter, or Pseudomonas spp.

CONCLUSIONS

The use of daily CHG bathing was not associated with a lower risk of gram-negative infections. Further, better designed trials with adequate power and with gram-negative infections as the primary end point are 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.

Chlorhexidine gluconate bathing to reduce methicillin-resistant Staphylococcus aureus acquisition

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is a virulent organism causing substantial morbidity and mortality in intensive care units. Chlorhexidine gluconate, a topical antiseptic solution, is effective against a wide spectrum of gram-positive and gram-negative bacteria, including MRSA. Objectives To examine the impact of a bathing protocol using chlorhexidine gluconate and bath basin management on MRSA acquisition in 5 adult intensive care units and to examine the cost differences between chlorhexidine bathing by using the bath-basin method versus using prepackaged chlorhexidine-impregnated washcloths.

METHODS

The protocol used a 4-oz bottle of 4% chlorhexidine gluconate soap in a bath basin of warm water. Patients in 3 intensive care units underwent active surveillance for MRSA acquisition; patients in 2 other units were monitored for a new positive culture for MRSA at any site 48 hours after admission.

RESULTS

Before the protocol, 132 patients acquired MRSA in 34333 patient days (rate ratio, 3.84). Afterwards, 109 patients acquired MRSA in 41376 patient days (rate ratio, 2.63). The rate ratio difference is 1.46 (95% CI, 1.12-1.90; P = .003). The chlorhexidine soap and bath basin method cost $3.18 as compared with $5.52 for chlorhexidine-impregnated wipes (74% higher).

CONCLUSIONS

The chlorhexidine bathing protocol is easy to implement, cost-effective, and led to decreased unit-acquired MRSA rates in a variety of adult intensive care units.

Antiseptic Body Washes for Reducing the Transmission of Methicillin-Resistant Staphylococcus aureus: A Cluster Crossover Study

In a cluster cross-over trial, targeted decolonization with octenidine body washes was not associated with reduction in MRSA transmission or infection

Background. Limiting the spread of methicillin-resistant Staphylococcus aureus (MRSA) within healthcare facilities where the organism is highly endemic is a challenge. The use of topical antiseptic agents may help interrupt the transmission of MRSA and reduce the risk of clinical infection. Octenidine dihydrochloride is a topical antiseptic that exhibits in vitro efficacy against a wide variety of bacteria, including S aureus.

Methods. We conducted a prospective cluster crossover study to compare the use of daily octenidine body washes with soap and water in patients identified by active surveillance cultures to be MRSA-colonized, to prevent the acquisition of MRSA in patients with negative screening swabs. Five adult medical and surgical wards and 2 intensive care units were selected. The study involved an initial 6-month phase using octenidine or soap washes followed by a crossover in each ward to the alternative product. The primary and secondary outcomes were the rates of new MRSA acquisitions and MRSA clinical infections, respectively.

Results. A total of 10 936 patients admitted for ≥48 hours was included in the analysis. There was a small reduction in MRSA acquisition in the intervention group compared with controls (3.0% vs 3.3%), but this reduction was not significant (odds ratio, 0.89; 95% confidence interval, .72–1.11; P = .31). There were also no significant differences in clinical MRSA infection or incidence of MRSA bacteremia.

Conclusions. This study suggests that the targeted use of routine antiseptic washes may not in itself be adequate to reduce the transmission of MRSA in an endemic hospital setting.

The Efficacy of Daily Bathing with Chlorhexidine for Reducing Healthcare-Associated Bloodstream Infections: A Meta-analysis

Design.

Systematic review and meta-analysis of randomized controlled trials and quasi-experimental studies to assess the efficacy of daily bathing with chlorhexidine (CHG) for prevention of healthcare-associated bloodstream infections (BSIs).

Setting.

Medical, surgical, trauma, and combined medical-surgical intensive care units (ICUs) and long-term acute care hospitals.

Participants.

Inpatients.

Methods.

Data on patient population, diagnostic criteria for BSIs, form and concentration of topical CHG, incidence of BSIs, and study design were extracted.

Results.

One randomized controlled trial and 11 nonrandomized controlled trials reporting a total of 137,392 patient-days met the inclusion criteria; 291 patients in the CHG arm developed a BSI over 67,775 patient-days, compared with 557 patients in the control arm over 69,617 catheter-days. CHG bathing resulted in a reduced incidence of BSIs: the pooled odds ratio using a random-effects model was 0.44 (95% confidence interval, 0.33–0.59; P< .00001). Statistical heterogeneity was moderate, with an I2 of 58%. For the subgroup of studies that examined central line–associated BSIs, the odds ratio was 0.40 (95% confidence interval, 0.27–0.59).

Conclusions.

Daily bathing with CHG reduced the incidence of BSIs, including central line-associated BSIs, among patients in the medical ICU. Further studies are recommended to determine the optimal frequency, method of application, and concentration of CHG as well as the comparative effectiveness of this strategy relative to other preventive measures available for reducing BSIs. Future studies should also examine the efficacy of daily CHG bathing in non-ICU populations at risk for BSI.

Infect Control Hosp Epidemiol 2012;33(3):257-267

Horizontal infection control strategy decreases methicillin-resistant Staphylococcus aureus infection and eliminates bacteremia in a surgical ICU without active surveillance

OBJECTIVE

Methicillin-resistant Staphylococcus aureus infection is a significant contributor to morbidity and mortality in hospitalized patients worldwide. Numerous healthcare bodies in Europe and the United States have championed active surveillance per the "search and destroy" model. However, this strategy is associated with significant economic, logistical, and patient costs without any impact on other hospital-acquired pathogens. We evaluated whether horizontal infection control strategies could decrease the prevalence of methicillin-resistant S. aureus infection in the ICU, without the need for active surveillance.

DESIGN AND SETTING

Retrospective, observational study in the surgical ICU of a tertiary care medical center in Boston, MA, from 2005 to 2012.

PATIENTS

A total of 6,697 patients in the surgical ICU.

INTERVENTIONS

Evidence-based infection prevention strategies were implemented in an iterative fashion, including 1) hand hygiene program with refresher education campaign, 2) chlorhexidine oral hygiene program, 3) chlorhexidine bathing, 4) catheter-associated bloodstream infection program, and 5) daily goals sheets.

MEASUREMENTS AND MAIN RESULTS

The prevalence of methicillin-resistant S. aureus infection fell from 2.66 to 0.69 per 1,000 patient days from 2005 to 2012, an average decrease of 21% per year. The biggest decline in rate of infection was detected in 2008, which may suggest that the catheter-associated bloodstream infection prevention program was particularly effective. Among 4,478 surgical ICU admissions over the last 5 years, not a single case of methicillin-resistant S. aureus bacteremia was observed.

CONCLUSIONS

Aggressive multifaceted horizontal infection control is an effective strategy for reducing the prevalence of methicillin-resistant S. aureus infection and eliminating methicillin-resistant S. aureus bacteremia in the ICU without the need for active surveillance and decontamination.

Hospital-wide infection control practice and Meticillin-resistant Staphylococcus aureus (MRSA) in the intensive care unit (ICU): an observational study

Objectives

To estimate trends in infection/colonisation with meticillin-resistant Staphylococcus aureus (MRSA) in an intensive care unit (ICU).

Design

Observational study of results of ICU admission and weekly screens for MRSA.

Setting and Participants

All ICU admissions in 2001–2012.

Interventions

ICU admissions were screened for MRSA throughout. In late 2006, screening was extended to the whole hospital and extra measures taken in ICU.

Main outcome measures

Prevalence of MRSA in ICU admissions and number acquiring MRSA therein.

Results

In all, 366 of 6565 admissions to ICU were MRSA positive, including 270 of 4466 coming from within the hospital in which prevalence increased with time prior to transfer to ICU. Prevalence in this group was 9.4% (8.2–10.6) in 2001–2006, decreasing to 3.4% (2.3–4.5) in 2007–2009 and 1.3% (0.6–2.0) in 2010–2012, p < 0.001, due to decreased prevalence in those spending >5 days on wards before ICU admission: 18.9% (15.6–22.2) in 2001–2006, 7.1% (4.0–10.2) in 2007–2009 and 1.6% (0.1–3.1) in 2010–2012, p < 0.001. In addition, 201 patients acquired MRSA within ICU, the relative risk being greater when known positives present: 4.34 (3.98–4.70), p < 0.001. Acquisition rate/1000 bed days decreased from 13.3 (11.2–15.4) in 2001–2006 to 3.6 (2.6–4.6) in 2007–2012, p < 0.0001. Of 41 ICU-acquired MRSA bacteraemias, 38 were in 2001–2006. The risk of bacteraemia in those acquiring MRSA decreased from 25% (18.1–31.9) in 2001–2006 to 6.1% (0–12.8) thereafter, p = 0.022.

Conclusions

Following better hospital-wide infection control, fewer MRSA-positive patients were admitted to ICU with a parallel decrease in acquisition therein. Better practice there reduced the risk of bacteraemia.

Influence of whole-body washing of critically ill patients with chlorhexidine on Acinetobacter baumannii isolates

BACKGROUND

Acinetobacter baumannii is 1 of the most important nosocomial pathogens and the causative agent of numerous types of infections, especially in intensive care units (ICUs). Our aim was to evaluate the effect of 2% chlorhexidine gluconate (CHG) whole-body washing of ICU patients on A baumannii in a tertiary care hospital.

METHODS

During the 6-month intervention period, 327 patients were subjected to whole-body bath with 2% CHG-impregnated wipes. blaIMP (active on imipenem), blaVIM (Verona integron-encoded metallo-ß-lactamase), and blaoxacillinase (OXA) of A baumannii were typed. Isolates were genotyped by pulsed-field gel electrophoresis. Minimum inhibitory concentrations (MIC) to CHG were determined by the agar dilution method and drug susceptibility determined using the broth microdilution method. Biofilm formation was determined by crystal violet staining.

RESULTS

We analyzed 80 isolates during the baseline period and 69 isolates during the intervention period. There was a decrease in the MIC₅₀ and MIC₉₀ values for CHG for isolates (8 mg/L and 16 mg/L, respectively). All isolates typed positive for OXA₅₁-like and 86% typed positive for OXA₂₄-like pulsed-field gel electrophoresis identified 2 main clone types. During the intervention period the frequency of clone A decreased and that of clone B increased. Both clones were OXA₂₄-like positive.

CONCLUSIONS

The A baumannii isolates recovered from patients who received body washing with 2% CHG presented with a significant decrease in CHG MIC values associated with a change in clonality correlating with increased biofilm production.

Systematic literature analysis and review of targeted preventive measures to limit healthcare-associated infections by meticillin-resistant Staphylococcus aureus

Meticillin-resistant Staphylococcus aureus (MRSA) is a major cause of healthcare-associated infections in Europe. Many examples have demonstrated that the spread of MRSA within healthcare settings can be reduced by targeted infection control measures. The aim of this systematic literature analysis and review was to summarise the evidence for the use of bacterial cultures for active surveillance the benefit of rapid screening tests, as well as the use of decolonisation therapies and different types of isolation measures. We included 83 studies published between 2000 and 2012. Although the studies reported good evidence supporting the role of active surveillance followed by decolonisation therapy, the effectiveness of single-room isolation was mostly shown in non-controlled studies, which should inspire further research regarding this issue. Overall, this review highlighted that when planning the implementation of preventive interventions, there is a need to consider the prevalence of MRSA, the incidence of infections, the competing effect of standard control measures (e.g. hand hygiene) and the likelihood of transmission in the respective settings of implementation.

Screening for methicillin-resistant Staphylococcus aureus: a comparative effectiveness review

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of health care-associated infections. Although the evidence in support of MRSA screening has been promising, a number of questions remain about the effectiveness of active surveillance.

METHODS

We searched the literature for studies that examined MRSA acquisition, MRSA infection, morbidity, mortality, harms of screening, and resource utilization when screening for MRSA carriage was compared with no screening or with targeted screening. Because of heterogeneity of the data and weaknesses in study design, meta-analysis was not performed. Strength of evidence (SOE) was determined using the system developed by the Grading of Recommendations Assessment, Development and Evaluation Working Group.

RESULTS

One randomized controlled trial and 47 quasi-experimental studies met our inclusion criteria. We focused on the 14 studies that addressed health care-associated outcomes and that attempted to control for confounding and/or secular trends, because those studies had the potential to support causal inferences. With universal screening for MRSA carriage compared with no screening, 2 large quasi-experimental studies found reductions in health care-associated MRSA infection. The SOE for this finding is low. For each of the other screening strategies evaluated, this review found insufficient evidence to determine the comparative effectiveness of screening.

CONCLUSIONS

Although there is low SOE that universal screening of hospital patients decreases MRSA infection, there is insufficient evidence to determine the consequences of universal screening or the effectiveness of other screening strategies.

Daily bathing with chlorhexidine-based soap and the prevention of Staphylococcus aureus transmission and infection

OBJECTIVE

Determine whether daily bathing with chlorhexidine-based soap decreased methicillin-resistant Staphylococcus aureus (MRSA) transmission and intensive care unit (ICU)-acquired S. aureus infection among ICU patients.

DESIGN

Prospective pre-post-intervention study with control unit.

SETTING

A 1,250-bed tertiary care teaching hospital.

PATIENTS

Medical and surgical ICU patients.

METHODS

Active surveillance for MRSA colonization was performed in both ICUs. In June 2005, a chlorhexidine bathing protocol was implemented in the surgical ICU. Changes in S. aureus transmission and infection rate before and after implementation were analyzed using time-series methodology.

RESULTS

The intervention unit had a 20.68% decrease in MRSA acquisition after institution of the bathing protocol (12.64 cases per 1,000 patient-days at risk before the intervention vs 10.03 cases per 1,000 patient-days at risk after the intervention; β, -2.62 [95% confidence interval (CI), -5.19 to -0.04]; P = .046). There was no significant change in MRSA acquisition in the control ICU during the study period (10.97 cases per 1,000 patient-days at risk before June 2005 vs 11.33 cases per 1,000 patient-days at risk after June 2005; β, -11.10 [95% CI, -37.40 to 15.19]; P = .40). There was a 20.77% decrease in all S. aureus (including MRSA) acquisition in the intervention ICU from 2002 through 2007 (19.73 cases per 1,000 patient-days at risk before the intervention to 15.63 cases per 1,000 patient-days at risk after the intervention [95% CI, -7.25 to -0.95]; P = .012)]. The incidence of ICU-acquired MRSA infections decreased by 41.37% in the intervention ICU (1.96 infections per 1,000 patient-days at risk before the intervention vs 1.15 infections per 1,000 patient-days at risk after the intervention; P = .001).

CONCLUSIONS

Institution of daily chlorhexidine bathing in an ICU resulted in a decrease in the transmission of S. aureus, including MRSA. These data support the use of routine daily chlorhexidine baths to decrease rates of S. aureus transmission and infection.

Interventions to reduce colonisation and transmission of antimicrobial-resistant bacteria in intensive care units: an interrupted time series study and cluster randomised trial

Background

Intensive care units (ICUs) are high-risk areas for transmission of antimicrobial-resistant bacteria, but no controlled study has tested the effect of rapid screening and isolation of carriers on transmission in settings with best-standard precautions. We assessed interventions to reduce colonisation and transmission of antimicrobial-resistant bacteria in European ICUs.

Methods

We did this study in three phases at 13 ICUs. After a 6 month baseline period (phase 1), we did an interrupted time series study of universal chlorhexidine body-washing combined with hand hygiene improvement for 6 months (phase 2), followed by a 12–15 month cluster randomised trial (phase 3). ICUs were randomly assigned by computer generated randomisation schedule to either conventional screening (chromogenic screening for meticillin-resistant Staphylococcus aureus [MRSA] and vancomycin-resistant enterococci [VRE]) or rapid screening (PCR testing for MRSA and VRE and chromogenic screening for highly resistant Enterobacteriaceae [HRE]); with contact precautions for identified carriers. The primary outcome was acquisition of resistant bacteria per 100 patient-days at risk, for which we calculated step changes and changes in trends after the introduction of each intervention. We assessed acquisition by microbiological surveillance and analysed it with a multilevel Poisson segmented regression model. We compared screening groups with a likelihood ratio test that combined step changes and changes to trend. This study is registered with ClinicalTrials.gov, number NCT00976638.

Findings

Seven ICUs were assigned to rapid screening and six to conventional screening. Mean hand hygiene compliance improved from 52% in phase 1 to 69% in phase 2, and 77% in phase 3. Median proportions of patients receiving chlorhexidine body-washing increased from 0% to 100% at the start of phase 2. For trends in acquisition of antimicrobial-resistant bacteria, weekly incidence rate ratio (IRR) was 0·976 (0·954–0·999) for phase 2 and 1·015 (0·998–1·032) for phase 3. For step changes, weekly IRR was 0·955 (0·676–1·348) for phase 2 and 0·634 (0·349–1·153) for phase 3. The decrease in trend in phase 2 was largely caused by changes in acquisition of MRSA (weekly IRR 0·925, 95% CI 0·890–0·962). Acquisition was lower in the conventional screening group than in the rapid screening group, but did not differ significantly (p=0·06).

Interpretation

Improved hand hygiene plus unit-wide chlorhexidine body-washing reduced acquisition of antimicrobial-resistant bacteria, particularly MRSA. In the context of a sustained high level of compliance to hand hygiene and chlorhexidine bathings, screening and isolation of carriers do not reduce acquisition rates of multidrug-resistant bacteria, whether or not screening is done with rapid testing or conventional testing.

Funding

European Commission.

Cost-benefit of infection control interventions targeting methicillin-resistant Staphylococcus aureus in hospitals: systematic review

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) incur significant costs. We aimed to examine the cost and cost-benefit of infection control interventions against MRSA and to examine factors affecting economic estimates. We performed a systematic review of studies assessing infection control interventions aimed at preventing spread of MRSA in hospitals and reporting intervention costs, savings, cost-benefit or cost-effectiveness. We searched PubMed and references of included studies with no language restrictions up to January 2012. We used the Quality of Health Economic Studies tool to assess study quality. We report cost and savings per month in 2011 US$. We calculated the median save/cost ratio and the save-cost difference with interquartile range (IQR) range. We examined the effects of MRSA endemicity, intervention duration and hospital size on results. Thirty-six studies published between 1987 and 2011 fulfilled inclusion criteria. Fifteen of the 18 studies reporting both costs and savings reported a save/cost ratio >1. The median save/cost ratio across all 18 studies was 7.16 (IQR 1.37-16). The median cost across all studies reporting intervention costs (n = 31) was 8648 (IQR 2025-19 170) US$ per month; median savings were 38 751 (IQR 14 206-75 842) US$ per month (23 studies). Higher save/cost ratios were observed in the intermediate to high endemicity setting compared with the low endemicity setting, in hospitals with <500-beds and with interventions of >6 months. Infection control intervention to reduce spread of MRSA in acute-care hospitals showed a favourable cost/benefit ratio. This was true also for high MRSA endemicity settings. Unresolved economic issues include rapid screening using molecular techniques and universal versus targeted screening.

Surveillance and management of multidrug-resistant microorganisms

Multidrug-resistant organisms are an established and growing worldwide public health problem and few therapeutic options remain available. The traditional antimicrobials (glycopeptides) for multidrug-resistant Gram-positive infections are declining in efficacy. New drugs that are presently available are linezolid, daptomicin and tigecycline, which have well-defined indications for severe infections, and talavancin, which is under Phase III trial for hospital-acquired pneumonia. Unfortunately the therapies available for multidrug-resistant Gram-negatives, including carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii and Enterobacteriaceae, are limited to only colistin and tigecycline. Both of these drugs are still not registered for severe infections, such as hospital acquired pneumonia. Consequently, as confirmed by scientific evidence, a multidisciplinary approach is needed. Surveillance, infection control procedures, isolation and antimicrobial stewardship should be implemented to reduce multidrug-resistant organism diffusion.

Daily bathing with octenidine on an intensive care unit is associated with a lower carriage rate of meticillin-resistant Staphylococcus aureus

Routine daily bathing of intensive care (ICU) patients with topical chlorhexidine reduces meticillin-resistant Staphylococcus aureus (MRSA) acquisition. The aim of this study was to investigate whether repeated five-day cycles of daily topical octenidine could result in a similar effect. This was a two-year retrospective, uncontrolled study in a mixed medical and surgical ICU/high dependency unit, demonstrating a 76% reduction in MRSA acquisition but no significant reduction in all ICU-acquired bacteraemias. Chlorhexidine use is increasing but resistance is being reported. This pilot study found a similar reduction in MRSA acquisition with octenidine as an alternative to chlorhexidine. Further study is required to establish causality.

Effectiveness of 2 methods of chlorhexidine bathing

The purposes of this study were to examine the impact of chlorhexidine on the transmission of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) on an inpatient oncology unit, compare the cost of 2 chlorhexidine bath delivery methods, and evaluate nursing time and satisfaction to administer the baths. MRSA and VRE transmission rates decreased from those during the previous years. Costs associated with bathing increased, but time to administer the bath decreased with the chlorhexidine cloths, and nursing staff reported satisfaction with their use.

Chlorhexidine body washing to control antimicrobial-resistant bacteria in intensive care units: a systematic review

PURPOSE

Infections caused by antimicrobial-resistant bacteria (AMRB) are increasing worldwide, especially in intensive care units (ICUs). Chlorhexidine body washing (CHG-BW) has been proposed as a measure to limit the spread of AMRB. We have systematically assessed the evidence on the effectiveness of CHG-BW in reducing colonization and infection with AMRB in adult ICU patients.

METHODS

PubMed, Embase, CINAHL, and OpenSigle databases were searched using synonyms for "intensive care unit," "hospital," and "chlorhexidine." All potentially relevant articles were examined by two independent reviewers. Inclusion was limited to studies with ICU patients as domain, providing outcomes related to colonization or infection with AMRB. Data from 16 studies were extracted; 9 were excluded because of assessed high risk of bias or inadequate analyses. The remaining studies differed markedly in (co-)interventions and case mix, which precluded pooling of data in a formal meta-analysis.

RESULTS

Incidences of MRSA acquisition were reduced significantly in three studies in which this was the primary endpoint. Significant reduction in MRSA infection rates was observed in only one of five studies. Carriage and bacteremia rates of VRE were assessed in one study, and both significantly declined. There were hardly any data on the effects of CHG-BW on antibiotic-resistant gram-negative bacteria (ARGNB).

CONCLUSIONS

CHG-BW may be effective in preventing carriage, and possibly bloodstream infections, with MRSA and VRE in different ICU settings. As CHG-BW protocols, co-interventions and case mix varied widely, attribution of these effects to CHG-BW alone should be done with care. Evidence that CHG-BW reduces carriage of or infections with ARGNB is lacking.

Staphylococcal decolonisation: an effective strategy for prevention of infection?

Staphylococcus aureus decolonisation--treatment to eradicate staphylococcal carriage--is often considered as a measure to prevent S aureus infection. The most common approach to decolonisation has been intranasal application of mupirocin either alone or in combination with antiseptic soaps or systemic antimicrobial agents. Some data support the use of decolonisation in surgical patients colonised with S aureus, particularly in those undergoing cardiothoracic procedures. Although this intervention has been associated with low rates of postoperative S aureus infection, whether overall rates of infection are also decreased is unclear. Patients undergoing chronic haemodialysis or peritoneal dialysis might benefit from decolonisation, although repeated courses of treatment are needed, and the effects are modest. Eradication of meticillin-resistant S aureus (MRSA) carriage has generally been difficult, and the role of decolonisation as an MRSA infection control measure is uncertain. The efficacy of decolonisation of patients with community-associated MRSA has not been established, and the routine use of decolonisation of non-surgical patients is not supported by data.

Randomized comparison of 2 protocols to prevent acquisition of methicillin-resistant Staphylococcus aureus: results of a 2-center study involving 500 patients

OBJECTIVE

To compare an interventional protocol with a standard protocol for preventing the acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in the intensive care unit (ICU).

DESIGN

Prospective, randomized, controlled, parallel-group, nonblinded clinical trial.

SETTING

Medical ICUs of 2 French university hospitals.

PARTICIPANTS

Five hundred adults with an expected length of stay in the ICU greater than 48 hours.

INTERVENTIONS

For the intervention group, the protocol required repeated MRSA screening, contact and droplet isolation precautions for patients at risk for MRSA at ICU admission and for MRSA-positive patients, and decontamination with nasal mupirocin and chlorhexidine body wash for MRSA-positive patients. For the standard group, the standard precautions protocol was used, and the results of repeated MRSA screening in the standard group were not communicated to investigators.

MAIN OUTCOME MEASURE

MRSA acquisition rate in the ICU. An audit was conducted to assess compliance with hygiene and isolation precautions.

RESULTS

In the intent-to-treat analysis ([Formula: see text]), the MRSA acquisition rate in the ICU was similar in the standard (13 [5.3%] of 243) and intervention (16 [6.5%] of 245) groups ([Formula: see text]). The audit showed that the overall compliance rate was 85.5% in the standard group and 84.1% in the intervention group ([Formula: see text]), although compliance was higher when isolation precautions were absent than when they were in place (88.2% vs 79.1%; [Formula: see text]). MRSA incidence rates were higher without isolation precautions (7.57‰) than with isolation precautions (2.36‰; [Formula: see text]).

CONCLUSIONS

Individual allocation to MRSA screening, isolation precautions, and decontamination do not provide individual benefit in reducing MRSA acquisition, compared with standard precautions, although the collective risk was lower during the periods of isolation.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT00151606.

Effect of systemic antibiotics and topical chlorhexidine on meticillin-resistant Staphylococcus aureus carriage in intensive care unit patients

Antibiotics and antiseptics have the potential to influence carriage and transmission of meticillin-resistant Staphylococcus aureus (MRSA), although effects are likely to be complex, particularly in a setting where multiple agents are used. Here admission and weekly MRSA screens and daily antibiotic and antiseptic prescribing data from 544 MRSA carriers on an intensive care unit (ICU) are used to determine the effect of these agents on short-term within-host MRSA carriage dynamics. Longitudinal data were analysed using Markov models allowing patients to move between two states: MRSA positive (detectable MRSA carriage) and MRSA negative (no detectable carriage). The effect of concurrent systemic antibiotic and topical chlorhexidine (CHX) on movement between these states was assessed. CHX targeted to MRSA screen carriage sites increased transition from culture positive to negative and there was also weaker evidence that it decreased subsequent transition from negative back to positive. In contrast, there was only weak and inconsistent evidence that any antibiotic influenced transition in either direction. For example, whereas univariate analysis found quinolones to be strongly associated with both increased risk of losing and then reacquiring MRSA carriage over time intervals of one day, no effect was seen with weekly models. Similar studies are required to determine the generalisability of these findings.

Potential of ceragenin CSA-13 and its mixture with pluronic F-127 as treatment of topical bacterial infections

AIMS

Ceragenin CSA-13 is a synthetic mimic of cationic antibacterial peptides, with facial amphiphilic morphology reproduced using a cholic acid scaffold. Previous data have shown that this molecule displays broad-spectrum antibacterial activity, which decreases in the presence of blood plasma. However, at higher concentrations, CSA-13 can cause lysis of erythrocytes. This study was designed to assess in vitro antibacterial and haemolytic activity of CSA-13 in the presence of pluronic F-127.

METHODS AND RESULTS

CSA-13 bactericidal activity against clinical strains of bacteria associated with topical infections and in an experimental setting relevant to their pathophysiological environment, such as various epithelial tissue fluids and the airway sputum of patients suffering from cystic fibrosis (CF), was evaluated using minimum inhibitory and minimum bactericidal concentration (MIC/MBC) measurements and bacterial killing assays. We found that in the presence of pluronic F-127, CSA-13 antibacterial activity was only slightly decreased, but CSA-13 haemolytic activity was significantly inhibited. CSA-13 exhibits bacterial killing activity against clinical isolates of Staphylococcus aureus, including methicillin-resistant strains, Pseudomonas aeruginosa present in CF sputa, and biofilms formed by different Gram (+) and Gram (-) bacteria. CSA-13 bactericidal action is partially compromised in the presence of plasma, but is maintained in ascites, cerebrospinal fluid, saliva, and bronchoalveolar lavage fluid. The synergistic action of CSA-13, determined by the use of a standard checkerboard assay, reveals an increase in CSA-13 antibacterial activity in the presence of host defence molecules such as the cathelicidin LL-37 peptide, lysozyme, lactoferrin and secretory phospholipase A (sPLA).

CONCLUSION

These results suggest that CSA-13 may be useful to prevent and treat topical infection.

SIGNIFICANCE AND IMPACT OF THE STUDY

Combined application of CSA-13 with pluronic F-127 may be beneficial by reducing CSA-13 toxicity.

Community-associated methicillin-resistant Staphylococcus aureus: epidemiology and clinical consequences of an emerging epidemic

Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations lacking risk factors for exposure to the health care system. This increase in the incidence of MRSA infection has been associated with the recognition of new MRSA clones known as community-associated MRSA (CA-MRSA). CA-MRSA strains differ from the older, health care-associated MRSA strains; they infect a different group of patients, they cause different clinical syndromes, they differ in antimicrobial susceptibility patterns, they spread rapidly among healthy people in the community, and they frequently cause infections in health care environments as well. This review details what is known about the epidemiology of CA-MRSA strains and the clinical spectrum of infectious syndromes associated with them that ranges from a commensal state to severe, overwhelming infection. It also addresses the therapy of these infections and strategies for their prevention.

Impact of active surveillance and contact isolation on transmission of methicillin-resistant Staphylococcus aureus in intensive care units in an area with high prevalence

BACKGROUND/PURPOSE

Previous research has suggested that active surveillance and early initiation of contact isolation (ASI) can control the nosocomial spread of methicillin-resistant Staphylococcus aureus (MRSA), especially among intensive care unit (ICU) patients. However, these interventions have never been implemented in Taiwan.

METHODS

This study was conducted from September 2005 to October 2006 to evaluate the effect of ASI on the spread of MRSA in two medical centers in Taiwan with a high prevalence of MRSA. One ICU from each hospital was selected as a study site. In phase I (the first 6 months), only active surveillance was introduced. In phase II (the final 6 months), ASI for patients who had positive MRSA cultures was implemented.

RESULTS

The incidence of acquiring MRSA during ICU stay did not differ significantly during phases I and II in hospital A (p = 0.940) and hospital B (p = 0.810). The independent risk factors for acquiring MRSA in the ICU were length of stay and presence of respiratory tract diseases.

CONCLUSION

This study demonstrated that, given the current resource limitations, ASI alone could not reduce MRSA transmission in two ICUs in Taiwan, where the MRSA prevalence was high.

Nasal decolonization of Staphylococcus aureus with mupirocin: strengths, weaknesses and future prospects

Staphylococcus aureus in the nose is a risk factor for endogenous staphylococcal infection. UK guidelines recommend the use of mupirocin for nasal decolonization in certain groups of patients colonized with methicillin-resistant S. aureus (MRSA). Mupirocin is effective at removing S. aureus from the nose over a few weeks, but relapses are common within several months. There are only a few prospective randomized clinical trials that have been completed with sufficient patients, but those that have been reported suggest that clearance of S. aureus from the nose is beneficial in some patient groups for the reduction in the incidence of nosocomial infections. There is no convincing evidence that mupirocin treatment reduces the incidence of surgical site infection. New antibiotics are needed to decolonize the nose because bacterial resistance to mupirocin is rising, and so it will become less effective. Furthermore, a more bactericidal antibiotic than mupirocin is needed, on the grounds that it might reduce the relapse rate, and so clear the patient of MRSA for a longer period of time than mupirocin.

Can we do better in controlling and preventing methicillin-resistant Staphylococcus aureus (MRSA) in the intensive care unit (ICU)?

Methicillin-resistant Staphylococcus aureus (MRSA) is prevalent in many hospitals, but many of its most serious clinical manifestations, such as bloodstream infection and ventilator-associated pneumonia, are seen in the intensive care unit (ICU). Many interventions to prevent and control MRSA were initially pioneered in the ICU and subsequently extended to the rest of the hospital. Recent studies confirm how many of these are effective. Active surveillance reveals higher numbers of cases when compared with the sole use of clinical specimens to identify MRSA-positive patients. Although one recent study from the UK has suggested that isolation has no impact on MRSA transmission in the ICU, current recommendations include isolation or cohorting, combined with decolonisation (e.g., mupirocin to the nose and chlorhexidine baths) as major control measures. However, the excessive use of mupirocin for nasal MRSA decolonisation leads to resistance. Improved compliance with hand hygiene recommendations and better antibiotic stewardship are also important. Rapid diagnosis such as PCR may utilise isolation facilities more effectively by identifying MRSA patients earlier. However, all these measures must be combined with adequate numbers of staff and suitable space and facilities, e.g., single rooms, to be maximally effective. Finally, while much can be done within the ICU itself, MRSA in the ICU often reflects the difficulties elsewhere in the acute hospital and the health service generally, in terms of the control and prevention of healthcare-associated infection.

Interventions to prevent transmission of antimicrobial-resistant bacteria in the intensive care unit

PURPOSE OF REVIEW

Healthcare-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus (VRE), and multidrug resistant Gram negative bacilli are a serious problem in ICUs. This review analyzes recent reports of interventions to prevent transmission of these organisms in the ICU.

RECENT FINDINGS

Two multicenter retrospective cohort studies demonstrated that surveillance cultures are necessary to identify the full reservoir of patients colonized with MRSA or VRE. A single center, interrupted time series study found that the incidence of healthcare-associated MRSA bacteremia was reduced after initiation of MRSA surveillance cultures. Other studies with various designs describe the effect of active surveillance on the use of isolation precautions, sustained improvements in compliance with hand hygiene and glove use associated with a multimodal intervention, reduced transmission of VRE associated with chlorhexidine bathing and improved environmental cleaning, and the efficacy of a MRSA decolonization regimen.

SUMMARY

Progress is being made in identifying interventions to prevent transmission of antimicrobial resistant bacteria in ICUs, although the strength of the evidence is limited compared with many therapeutic interventions. Large MRSA control initiatives launched during 2006 and 2007 may build on this work; their effects should be evaluated using proper study designs and analyses.