Vancomycin-resistant Enterococcus Acquisition Research Articles

Chlorhexidine bathing to prevent healthcare-associated vancomycin-resistant Enterococcus infections: A cluster quasi-experimental controlled study at intensive care units

Vancomycin-resistant Enterococcus (VRE), a multidrug-resistant, difficult-to-treat pathogen of healthcare-associated infections (HAIs), is now endemic at many intensive care units (ICUs). Chlorhexidine (CHG) bathing is a simple and highly effective intervention to decrease VRE acquisition, but its effect on VRE-HAIs has not been assessed in prospective studies at ICUs. This is a cluster quasi-experimental controlled study. Under active VRE surveillance and contact isolation of all identified VRE carriers, four ICUs were assigned to provide 2% CHG bathing for all patients on a daily basis (CHG group) during the intervention period, while another four ICUs were assigned to provide standard care without CHG bathing for all patients (standard care group) during the same period. The CHG group (n=1501) had a 62% lower crude incidence of VRE-HAIs during the intervention period, compared with the baseline period (1.0 vs. 2.6 per thousand patient-days, P=0.009), while VRE-HAIs incidence did not change in standard care group (n=3299) (1.1 vs. 0.5 per thousand patient-days, P=0.139). In multivariable analyses, CHG bathing was independently associated with a 70% lower risk of VRE-HAIs (adjusted odds ratio [OR] 0.3, 95% confidence interval [CI], 0.2 to 0.7, P=0.006). In contrast, standard care during the same period had no effect on the risk of VRE-HAIs (adjusted OR 1.8, 95% CI: 0.7 to 4.7, P=0.259). CHG bathing is a highly effective approach to prevent VRE-HAIs at ICUs, in the context of active VRE surveillance with contact isolation.

Chlorhexidine Bathing Strategies for Multidrug-Resistant Organisms: A Summary of Recent Evidence.

ObjectiveThe aim of the study was to summarize the latest evidence for patient bathing with a 2% to 4% chlorhexidine gluconate solution to reduce multidrug-resistant organism (MDRO) transmission and infection.MethodsWe searched 3 databases (CINAHL, MEDLINE, and Cochrane) for a combination of the key words “chlorhexidine bathing” and MeSH terms “cross-infection prevention,” “drug resistance, multiple, bacterial,” and “drug resistance, microbial.” Articles from January 1, 2008, to December 31, 2018, were included, as well as any key articles published after December 31.ResultsOur findings focused on health care–associated infections (HAIs) and 3 categories of MDROs: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and carbapenem-resistant Enterobacteriaceae (CRE). Chlorhexidine bathing reduces MRSA acquisition and carriage, but not all studies found significant reductions in MRSA infections. Several studies found that chlorhexidine bathing reduced VRE acquisition and carriage, and one study showed lower VRE infections in the bathing group. Two studies found that bathing reduced CRE carriage (no studies examined CRE infections). Two very large studies (more than 140,000 total patients) found bathing significantly reduced HAIs, but these reductions may be smaller when HAIs are already well controlled by other means.ConclusionsThere is a high level of evidence supporting chlorhexidine bathing to reduce MDRO acquisition; less evidence is available on reducing infections. Chlorhexidine bathing is low cost to implement, and adverse events are rare and resolve when chlorhexidine use is stopped. There is evidence of chlorhexidine resistance, but not at concentrations in typical use. Further research is needed on chlorhexidine bathing’s impact on outcomes, such as mortality and length of stay.

Risk factors for vancomycin-resistant enterococcus acquisition during a large outbreak in patients aged 65\u2009years and older

BackgroundIn the context of an aging population, identifying risk factors for Vancomycin-resistant enterococci (VRE), specific to older people, is important. However, if age is a known risk factor for VRE infection, a limited number of studies have focused on older patients. This study aimed to identify potential risk factors for VRE acquisition in a population aged 65 years and older, during a large VRE outbreak that occurred in a teaching hospital in Lyon, France, from December 2013 to July 2014.MethodsThe present retrospective, multi-center, descriptive, and analytical study used part of a previous cohort, and included only a sub-group of patients aged 65 years and older. The analysis of the factors included in the original study was completed with factors more specific to geriatric patients. Inclusion criteria were patients aged 65 years and older, in contact with a VRE index patient. Patients were screened by rectal swabs. Univariate and multivariate logistic regression analyses were performed.ResultsA total of 180 VRE contacts were included and 18 patients became carriers. Multivariate analysis showed that risk factors for VRE acquisition in older people included major contact type (RR: 5.31, 95%CI [1.33; 21.19]), number of antibiotics used (RR: 1.36, 95%CI [1.04; 1.76]), a score of McCabe = 2 (RR: 116.39, 95%CI [5.52; 2455.98]), ethylism (RR: 5.50, 95%CI [1.49; 20.25]), and dementia (RR: 7.50, 95%CI [1.89; 29.80]).ConclusionsThis study was able to demonstrate risk factors for VRE acquisition in older people. These risk factors should be taken into account when in the presence of older people in a VRE infected unit.

Vancomycin-Resistant Enterococcus Acquisition in a Tertiary Care Hospital: Testing the Roles of Antibiotic Use, Proton Pump Inhibitor Use, and Colonization Pressure.

BackgroundVancomycin-resistant Enterococcus (VRE) is a leading cause of healthcare-associated infections, and asymptomatic colonization precedes infection. VRE continues to spread despite widespread application of pathogen-specific control guidelines. A better understanding of the risk factors for transmission is needed.MethodsA retrospective matched case-control study was performed from June 2013 through December 2016 in a single institution. Patients in 6 intensive care units, 1 hematology and oncology unit, and 1 bone marrow transplant unit were screened by means of rectal swab sampling on admission and weekly thereafter. Case patients had a negative swab sample followed by a positive sample >3 days after admission. Controls were closely matched to case patients based on time from admission to the second swab sample, unit in which the second sample was obtained, and date of admission. Comorbidity data, procedures, healthcare settings and exposures, culture data, and duration of antibiotic and proton pump inhibitor (PPI) therapy were abstracted from the electronic medical record. A multivariable risk factor model for conversion was generated using purposeful selection.ResultsA total of 551 case patients were matched with controls. The largest modifiable effects on VRE acquisition were ≥1 day of vancomycin therapy (odd ratio, 1.98; P < .001), ≥1 day of aerobic antibiotic therapy (1.90; P < .001), and a dose-dependent effect of PPI therapy (odds ratio per day of therapy, 1.09; P < .001). Colonization pressures from patients identified to be carriers and placed in contact precautions did not confer increased risk.ConclusionsDecreasing PPI use and preventing the inappropriate initiation of antibiotic therapy are modifiable targets to decrease VRE transmission in the hospital.

The local hospital milieu and healthcare-associated vancomycin-resistant enterococcus acquisition

Vancomycin-resistant enterococcus (VRE) causes 4% of all healthcare-associated infections in the USA. The process by which the local hospital milieu contributes to VRE acquisition is not fully understood. To determine the importance of specific factors within the local hospital environment for healthcare-associated VRE acquisition. This retrospective cohort study included patients admitted to six intensive care units at an academic medical centre from January 2012 to December 2016 with negative rectal VRE cultures on admission. VRE acquisition was defined as a positive surveillance swab performed at any time after the initial negative swab during the index hospitalization. The exposures of interest were VRE colonization pressure, VRE importation pressure, and use of vancomycin. Multivariable Cox proportional hazards modelling was performed, with patients followed until VRE acquisition, death, or for up to 30 days. Of 8485 patients who were initially VRE negative, 161 patients acquired VRE. On univariate analysis, patients with VRE acquisition were more likely to have received vancomycin, to have had a neighbouring patient who received vancomycin, to have high VRE importation pressure, or to have high VRE colonization pressure. On multivariable analysis, only high VRE colonization pressure was an independent predictor of VRE acquisition (adjusted hazard ratio: 1.79; 95% confidence interval: 1.19-2.70). VRE colonization pressure was the most important risk factor for healthcare-associated VRE acquisition, regardless of VRE importation pressure. Interventions seeking to reduce VRE acquisition should focus on minimizing transmission between patients with known VRE and the local hospital environment.

Factors associated with Vancomycin-resistant Enterococcus acquisition during a large outbreak.

Between 2013 and 2014 a Vancomycin-resistant Enterococci (VRE) outbreak occurred in a teaching hospital in France. The outbreak was significant possibly due to the lack of implementation of recommended control measures. The aim of this study was to identify the effect of the lack of adherence to control measures for prevention of VRE acquisition in contact patients taking into account individual risk factors. Contact patients (first two months of the outbreak) with VRE acquisition were compared to patients without VRE acquisition (univariate and logistic regression), in terms of institutional characteristics (unit of hospitalization and isolation measures) and risk factors. Between December 2013 and February 2014, 282 contact patients were included in the study. The prevalence of VRE acquisition was 6.4% (18/282). Significant risk factors for VRE acquisition according to logistic regression analysis were; lack of isolation, hospitalization in the same hospital unit as a VRE carrier patient and lack of isolation (RR=856.8, p=0.001), hospitalization in a specific unit (RR=927.4, p=0.002), McCabe score equal to 2 (RR=5233.6, p=0.008), age (RR=1.2 by year, p=0.011), hemodialysis (RR=36.1, p=0.011), central venous catheter (RR=25.4, p=0.021) and surgery (RR=0.012, p=0.007). Antibiotic use was a significant risk factor for VRE acquisition using univariate analysis (p<10-3). The findings confirm that the factors focused on by the study (lack of isolation and dedicated unit) had a significant effect on VRE acquisition as patient associated factors. It highlights the importance of observance of the guidelines.

Effect of chlorhexidine bathing in preventing infections and reducing skin burden and environmental contamination: A review of the literature.

Chlorhexidine bathing is effective in reducing levels of pathogens on skin. In this review, we examine the evidence that chlorhexidine bathing can prevent colonization and infection with health care-associated pathogens and reduce dissemination to the environment and the hands of personnel. The importance of education and monitoring of compliance with bathing procedures is emphasized in order to optimize chlorhexidine bathing in clinical practice.

Identification of subclinical transmission of vancomycin-resistant enterococcus within an intensive care unit in Taiwan.

Colonization, infection, and clonal dissemination of vancomycin-resistant enterococcus (VRE) have been reported in the literature. We aimed to investigate the incidence rate of VRE acquisition and route of transmission of VRE within the medical intensive care unit (ICU) to prove whether subclinical transmission occurs in medical ICUs. Between March 1, 2012 and September 30, 2013, rectal cultures were obtained from all inpatients on admission and after admission to medical ICU. Strain types of VRE were determined by both multilocus sequence typing and pulsed-field gel electrophoresis. A total of 66 of the 405 rectal swab surveillance cultures obtained from 46 inpatients were positive for VRE, among which 27 inpatients were culture-positive for VRE on admission to medical ICU, and 19 inpatients were initially culture-negative but converted to culture-positive after admission. All isolates carried vanA gene consisting of 51 Enterococcus gallinarum, 13 Enterococcus faecium, and two Eenterococcus casseliflavus. Of the 51E. gallinarum isolates, 40 were type ST 341, seven were ST 252, two were ST 78, and two were ST 64. The Enterococcus spp., MLST and PFGE subtypes were almost similar among these two groups of inpatients. Linezolid and tigecycline were most active against VRE invitro. Subclinical VRE cross transmission may occur in ICU. Active surveillance and maximal barrier precautions of VRE are required at ICU with high colonization rate of VRE and shall be beneficial.

Vancomycin-resistant enterococcus (VRE) transmission and risk factors in contacts of VRE carriers.

During a 2-year period, the vancomycin-resistant enterococcus (VRE) acquisition rate was 10.9% (40/368) in patients who had shared a room with a newly detected VRE carrier. Exposure to vancomycin and to anti-anaerobic antibiotics were identified as independent risk factors for VRE acquisition. Sensitivity of the first rectal VRE screening was less than 50%.

Universal Glove and Gown Use and Acquisition of Antibiotic-Resistant Bacteria in the ICU

Antibiotic-resistant bacteria are associated with increased patient morbidity and mortality. It is unknown whether wearing gloves and gowns for all patient contact in the intensive care unit (ICU) decreases acquisition of antibiotic-resistant bacteria. To assess whether wearing gloves and gowns for all patient contact in the ICU decreases acquisition of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) compared with usual care. Cluster-randomized trial in 20 medical and surgical ICUs in 20 US hospitals from January 4, 2012, to October 4, 2012. In the intervention ICUs, all health care workers were required to wear gloves and gowns for all patient contact and when entering any patient room. The primary outcome was acquisition of MRSA or VRE based on surveillance cultures collected on admission and discharge from the ICU. Secondary outcomes included individual VRE acquisition, MRSA acquisition, frequency of health care worker visits, hand hygiene compliance, health care–associated infections, and adverse events. From the 26,180 patients included, 92,241 swabs were collected for the primary outcome. Intervention ICUs had a decrease in the primary outcome of MRSA or VRE from 21.35 acquisitions per 1000 patient-days (95% CI, 17.57 to 25.94) in the baseline period to 16.91 acquisitions per 1000 patient-days (95% CI, 14.09 to 20.28) in the study period, whereas control ICUs had a decrease in MRSA or VRE from 19.02 acquisitions per 1000 patient-days (95% CI, 14.20 to 25.49) in the baseline period to 16.29 acquisitions per 1000 patient-days (95% CI, 13.48 to 19.68) in the study period, a difference in changes that was not statistically significant (difference, −1.71 acquisitions per 1000 person-days, 95% CI, −6.15 to 2.73; P = .57). For key secondary outcomes, there was no difference in VRE acquisition with the intervention (difference, 0.89 acquisitions per 1000 person-days; 95% CI, −4.27 to 6.04, P = .70), whereas for MRSA, there were fewer acquisitions with the intervention (difference, −2.98 acquisitions per 1000 person-days; 95% CI, −5.58 to −0.38; P = .046). Universal glove and gown use also decreased health care worker room entry (4.28 vs 5.24 entries per hour, difference, −0.96; 95% CI, −1.71 to −0.21, P = .02), increased room-exit hand hygiene compliance (78.3% vs 62.9%, difference, 15.4%; 95% CI, 8.99% to 21.8%; P = .02) and had no statistically significant effect on rates of adverse events (58.7 events per 1000 patient days vs 74.4 events per 1000 patient days; difference, −15.7; 95% CI, −40.7 to 9.2, P = .24). The use of gloves and gowns for all patient contact compared with usual care among patients in medical and surgical ICUs did not result in a difference in the primary outcome of acquisition of MRSA or VRE. Although there was a lower risk of MRSA acquisition alone and no difference in adverse events, these secondary outcomes require replication before reaching definitive conclusions. clinicaltrials.gov Identifier: NCT0131821.

Multidrug-resistant bacteria colonization amongst patients newly admitted to a geriatric unit: A prospective cohort study

To determine prevalence, incidence and risk factors of colonization by extended-spectrum β-lactamase-producing Enterobacteriacae (ESBLE), methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE) in aged subjects admitted to an acute geriatric unit at a teaching hospital. During 12 months, 337 patients were screened by nasal, oropharyngeal, groin, axillary and rectal swabs upon admission and at discharge. The prevalence of ESBLE, MRSA and VRE carriage upon admission was 11.6%, 7.5% and 0.6%, respectively. The incidence density of ESBLE and MRSA carriage was respectively of 1.77 and 2.40 new cases for 1000 patient-days. No cases of VRE acquisition were found. Risk factors for ESBLE colonization on admission were: multiple contacts with the hospital within the previous year, chronic catheter use and a high level of dependency. For MRSA, risk factors were: chronic wounds, anti-acid use and a high level of dependency. This study shows a high prevalence of asymptomatic colonization of ESBL-producing Escherichia coli in patients admitted to an acute geriatric ward, as high as MRSA carriage. A low functional status is a common risk factor both for ESBLE and for MRSA colonization and it highlights the need to reinforce infection control measures.

Molecular Epidemiology and Risk Factors for Colonization by Vancomycin-ResistantEnterococcusin Patients with Hematologic Malignancies

To study the molecular epidemiology of vancomycin-resistant Enterococcus (VRE) colonization and to identify modifiable risk factors among patients with hematologic malignancies. A hematology-oncology unit with high prevalence of VRE colonization. Patients with hematologic malignancies and hematopoietic stem cell transplantation recipients admitted to the hospital. Patients underwent weekly surveillance by means of perianal swabs for VRE colonization and, if colonized, were placed in contact isolation. We studied the molecular epidemiology in fecal and blood isolates by pulsed-field gel electrophoresis over a 1-year period. We performed a retrospective case-control study over a 3-year period. Cases were defined as patients colonized by VRE, and controls were defined as patients negative for VRE colonization. Case patients and control patients were matched by admitting service and length of observation time. Molecular genotyping demonstrated the primarily polyclonal nature of VRE isolates. Colonization occurred at a median of 14 days. Colonized patients were characterized by longer hospital admissions. Previous use of ceftazidime was associated with VRE colonization (P < .001), while use of intravenous vancomycin and antibiotics with anaerobic activity did not emerge as a risk factor. There was no association with neutropenia or presence of colonic mucosal disruption, and severity of illness was similar in both groups. Molecular studies showed that in the majority of VRE-colonized patients the strains were unique, arguing that VRE acquisition was sporadic rather than resulting from a common source of transmission. Patient-specific factors, including prior antibiotic exposure, rather than breaches in infection control likely predict for risk of fecal VRE colonization.

Incidence and risk factors of vancomycin-resistant enterococcus colonization in burn unit patients

This study was aimed to identify the incidence of vancomycin-resistant enterococcus (VRE) colonization in burn patients, to collate risk factors for colonization and to determine the VRE resistance profile to different antimicrobial agents. This prospective study was carried out on the burn unit, during the period from September 2008 to January 2010, in 128 patients who were hospitalized at least 3 weeks or more. Periodic swabs were taken from burn wound, rectal, axillary, umblicaly and throat regions of the patients on admission and 7th, 14th, 21st days of hospitalization. Demographics and known risk factors were retrieved and assessed by statistical methods. Only 20 patients (15.6%) were colonized with enterococci on admission and these strains isolated from rectal, umblical and throat samples were sensitive to vancomycin. Initial VRE isolation was made in the first samples from the rectum of two patients on the 7th day. The rates of rectal, umblical, throat and axillary colonization increased to 21.9%, 3.1%, 3.1% and 3.1% at 28th day, respectively. VRE strains were the first isolated from burn wounds of only one patient (0.8%) on the 14th day and the colonization rate increased to 7.0% at the 28th day. Our study indicated that rectal colonization was seen more than other sites of colonization and was strictly correlate to colonizing enterococci between burn wound and other body regions. Multivariate analyses showed that glycopeptide use, burn depth and total burn surface area were independent risk factors for acquisition of VRE. All VSE strains were susceptible to teicoplanin, tigecycline and linezolid. VSE strains were more resistant to gentamicin and streptomycin, and VRE strains were more resistant to penicillin and ampicillin. The present study showed tigecycline and linezolid to be most active agents against VRE strains. The determined VRE colonization and risk factors of VRE acquisition are expected to be useful in establishing guidelines for preventing VRE infection in burn unit.

Acquisition of Rectal Colonization by Vancomycin-Resistant Enterococcus among Intensive Care Unit Patients Treated with Piperacillin-Tazobactam versus Those Receiving Cefepime-Containing Antibiotic Regimens

In contrast to expanded-spectrum cephalosporins, beta-lactam-beta-lactamase inhibitor combinations such as piperacillin-tazobactam have rarely been associated with vancomycin-resistant Enterococcus (VRE) colonization and infection. In mice, piperacillin-tazobactam has sufficient antienterococcal activity to inhibit the establishment of colonization during treatment, but this effect has not been confirmed in human patients. We prospectively evaluated the acquisition of rectal colonization by VRE among intensive care unit patients receiving antibiotic regimens containing piperacillin-tazobactam versus those receiving cefepime, an expanded-spectrum cephalosporin with minimal antienterococcal activity. Rectal swabs were obtained weekly and were cultured for VRE. For 146 patients with a negative rectal swab for VRE prior to therapy, there was no significant difference in the frequency of VRE acquisition between patients receiving piperacillin-tazobactam- and cefepime-containing regimens (19/72 [26.4%] and 23/74 [31.1%], respectively; P = 0.28). Of the 19 patients who acquired VRE in association with piperacillin-tazobactam, 10 (53%) developed the new detection of VRE during therapy. Patients initiated on treatment with cefepime-containing regimens were significantly more likely than those initiated on treatment with piperacillin-tazobactam-containing regimens to have received antibiotic therapy in the prior 30 days (55/74 [74.3%] and 22/72 [30.6%], respectively; P < 0.001). These findings suggest that piperacillin-tazobactam- and cefepime-containing antibiotic regimens may be associated with the frequent acquisition of VRE in real-world intensive care unit settings. Although piperacillin-tazobactam inhibits the establishment of VRE colonization in mice when exposure occurs during treatment, our data suggest that this agent may not prevent the acquisition of VRE in patients.

Does vancomycin prescribing intervention affect vancomycin-resistant enterococcus infection and colonization in hospitals? A systematic review

BackgroundVancomycin resistant enterococcus (VRE) is a major cause of nosocomial infections in the United States and may be associated with greater morbidity, mortality, and healthcare costs than vancomycin-susceptible enterococcus. Current guidelines for the control of VRE include prudent use of vancomycin. While vancomycin exposure appears to be a risk factor for VRE acquisition in individual patients, the effect of vancomycin usage at the population level is not known. We conducted a systematic review to determine the impact of reducing vancomycin use through prescribing interventions on the prevalence and incidence of VRE colonization and infection in hospitals within the United States.MethodsTo identify relevant studies, we searched three electronic databases, and hand searched selected journals. Thirteen studies from 12 articles met our inclusion criteria. Data were extracted and summarized for study setting, design, patient characteristics, types of intervention(s), and outcome measures. The relative risk, 95% confidence interval, and p-value associated with change in VRE acquisition pre- and post-vancomycin prescription interventions were calculated and compared. Heterogeneity in study results was formally explored by stratified analysis.ResultsNo randomized clinical trials on this topic were found. Each of the 13 included studies used a quasi-experimental design of low hierarchy. Seven of the 13 studies reported statistically significant reductions in VRE acquisition following interventions, three studies reported no significant change, and three studies reported increases in VRE acquisition, one of which reported statistical significance. Results ranged from a reduction of 82.5% to an increase of 475%. Studies of specific wards, which included sicker patients, were more likely to report positive results than studies of an entire hospital including general inpatients (Fisher's exact test 0.029). The type of intervention, endemicity status, type of study design, and the duration of intervention were not found to significantly modify the results. Among the six studies that implemented vancomycin reduction strategies as the sole intervention, two of six (33%) found a significant reduction in VRE colonization and/or infection. In contrast, among studies implementing additional VRE control measures, five of seven (71%) reported a significant reduction.ConclusionIt was not possible to conclusively determine a potential role for vancomycin usage reductions in controlling VRE colonization and infection in hospitals in the United States. The effectiveness of such interventions and their sustainability remains poorly defined because of the heterogeneity and quality of studies. Future research using high-quality study designs and implementing vancomycin as the sole intervention are needed to answer this question.