Carriage Of Vancomycin-resistant Enterococci Research Articles

Application of a Model Using Prior Healthcare Information to Predict Multidrug-Resistant Organism (MDRO) Carriage

Background: Early identification of patients colonized with MDROs can help healthcare facilities improve infection control and treatment. We evaluated whether a model previously validated to predict carbapenem-resistant Enterobacterales (CRE) carriage on hospital admission (area under the curve [AUC]=0.86, Lin et al. OFID 2019) would generalize to predict a patient’s likelihood of CRE and non-CRE MDRO colonization at the time of medical intensive care unit (MICU) admission. Methods: We analyzed data collected previously in a retrospective observational cohort study of patients admitted to Rush University Medical Center’s MICU from 1/2017-1/2018 and screened within the first two days for rectal MDRO colonization. Organisms of interest included CRE, carbapenem-resistant Pseudomonas aeruginosa (CRPA), vancomycin-resistant enterococci (VRE), and third-generation cephalosporin-resistant Enterobacterales (3GCR-E). Methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization at admission was determined by routine clinical screening. Each patient’s first MICU admission during the study period was linked to Illinois’ hospital discharge database and assigned a CRE colonization risk probability using the existing model. Model covariates were age, and during the prior 365 days, number of short-term acute care hospitalizations (STACH) and mean STACH length of stay, number of long-term acute care hospitalizations (LTACH) and mean LTACH length of stay, prior hospital admission with an ICD-10 diagnosis code indicating bacterial infection, and current admission to LTACH. Predictive value of the model was evaluated by receiver operating characteristic (ROC) curves. Results: We analyzed 1237 MICU admissions. MDRO admission prevalence is shown in the Table. The model performed well to predict carriage of healthcare-associated MDROs, including CRE, CRPA, composite CR-MDROs (CRE & CRPA), and VRE. However, the model performed poorly for MDROs with known community reservoirs, including 3GCR-E and MRSA (Table). In general, MDRO admission prevalence increased in parallel with predicted CRE colonization risk (Figure). The number needed to screen (NNS) to detect one healthcare-associated MDRO carrier was inversely related to the CRE colonization risk score. For example, NNS in the total cohort compared to those with CRE risk score of >0.5% was: CRE 111 vs 32 patients, CRPA 333 vs 42 patients, composite CR-MDRO 83 vs 18 patients, and VRE 12 vs 4 patients. However, higher CRE risk score cutoff was inversely related to screening sensitivity. Conclusion: A prediction model using prior healthcare exposure information successfully discriminated patients likely to harbor healthcare-associated MDROs upon MICU admission. Prediction scores generated by a public-health accessible database could be used to target screening/isolation or enact protective measures for high-risk patients.

Nutritional Strategies To Improve VRE Control

The rise of Vancomycin-resistant enterococci (VRE) strains among cellular therapy recipients raises concerns due to increased morbidity, mortality, and hospitalization costs, particularly impacting transplanted patients with diminished survival expectations. Recent research linking lactose to Enterococcus growth and graft-versus-host disease (GVHD) emphasizes the need for data on reducing lactose in the diets of VRE-carrying patients, especially in cellular therapy contexts like CAR-T or allogeneic hematopoietic stem cell transplantation. Responding to elevated VRE positivity rates in rectal swabs among patients in our BMT Unit, a unique nutritional strategy was implemented, introducing lactose-free milk and strictly enforcing lactose-free diets. This approach resulted in a significant reduction in VRE carriers, with a 16% positivity rate in the Lactose Group versus 3.6% in the Lactose-Free Group, as of June 2023. These results indicate the potential efficacy of this innovative nutritional strategy in high-risk departments, such as BMT Units and Intensive Care Units, with implications for reducing isolation strategies and inappropriate antibiotic use in cases of VRE colonization.

Epidemiology and infection control of vancomycin-resistant enterococci at a German university hospital: A three-year retrospective cohort study.

Vancomycin-resistant enterococci (VRE) occur in hospitalized patients, causing both infection and colonization. In recent years, there has been an increase in VRE in German and other hospitals, raising the question of how to control this epidemic best. To better understand the specific epidemiology and to guide infection control, we conducted a retrospective cohort study analyzing all patients with VRE at Hannover Medical School, a tertiary university clinic in Germany that specializes in solid organ transplantation. Epidemiologic and clinical characteristics of patients with VRE from 2015-2017 were collected. Basic epidemiologic parameters, including VRE incidence and incidence density, were calculated. Independent risk factors for nosocomial VRE infection compared to colonization were assessed using a logistic regression model. There were 1,492 VRE cases corresponding to 822 individual patients. The incidence was 0.8 VRE cases per 100 cases. A total of 536 (35.9%) of the 1,492 VRE cases were acquired nosocomially. Of the 1,492 cases, 912 cases had VRE-positive samples (894 Enterococcus (E.) faecium and 18 E. faecalis) in our hospital laboratory and the remaining cases were known VRE carriers. The vanB-phenotype was observed in 369 of the 894 (41.3%) E. faecium isolates and in 6 of the 18 (33.3%) E. faecalis isolates. There was an increase over time in the vanB-phenotype proportion in E. faecium (2015: 63 of 171, 36.8%, 2016: 115 of 322, 35.7% and 2017: 191 of 401, 47.6%). A total of 107 cases had a VRE infection (7.2% of all VRE cases) according to the criteria of the German National Reference Center for Surveillance of Nosocomial Infections. The remaining cases were only colonized. Among other factors, leukocytopenia (<1,000/μL), the use of a central venous catheter and the visceral surgery medical specialty were independently associated with nosocomial VRE infection. VRE imposed a relevant and increasing infection control burden at our hospital. Nosocomial VRE infection was predominantly found in certain medical specialties, such as hematology and oncology and visceral surgery. Infection control efforts should focus on these highly affected patient groups/specialties.

Predicting infection risk from surveillance cultures: frustrating or foretelling?

The global burden of morbidity and mortality due to multidrug-resistant infections is high, and in-vitro inactive empirical antibiotic therapy is a well known risk factor for poor outcomes. 1 Antimicrobial Resistance CollaboratorsGlobal burden of bacterial antimicrobial resistance in 2019: a systematic analysis. Lancet. 2022; 399: 629-655 Summary Full Text Full Text PDF PubMed Scopus (1171) Google Scholar , 2 Kadri SS Lai YL Warner S et al. Inappropriate empirical antibiotic therapy for bloodstream infections based on discordant in-vitro susceptibilities: a retrospective cohort analysis of prevalence, predictors, and mortality risk in US hospitals. Lancet Infect Dis. 2021; 21: 241-251 Summary Full Text Full Text PDF PubMed Scopus (57) Google Scholar Studies have shown that colonisation with resistant pathogens increases the subsequent risk of infection by those same strains. However, when operationalising this principle, deciding how often to use specific broad-spectrum antibiotics if the patient is colonised with a particular pathogen warrants an improved understanding of the relative size of infection risks across different pathogens, host types, and time. 3 Denkel LA Maechler F Schwab F et al. Infections caused by extended-spectrum beta-lactamase-producing Enterobacterales after rectal colonization with ESBL-producing Escherichia coli or Klebsiella pneumoniae. Clin Microbiol Infect. 2020; 26: 1046-1051 Summary Full Text Full Text PDF PubMed Scopus (18) Google Scholar , 4 Tseng W-P Chen Y-C Chen S-Y Chen S-Y Chang S-C Risk for subsequent infection and mortality after hospitalization among patients with multidrug-resistant Gram-negative bacteria colonization or infection. Antimicrob Resist Infect Control. 2018; 7: 93 Crossref PubMed Scopus (33) Google Scholar , 5 Giannella M Bartoletti M Conti M Righi E Carbapenemase-producing Enterobacteriaceae in transplant patients. J Antimicrob Chemother. 2021; 76: i27-i39 Crossref Scopus (6) Google Scholar , 6 Tischendorf J de Avila RA Safdar N Risk of infection following colonization with carbapenem-resistant Enterobactericeae: a systematic review. Am J Infect Control. 2016; 44: 539-543 Summary Full Text Full Text PDF PubMed Scopus (143) Google Scholar Roel P J Willems and colleagues should be congratulated for their systematic review and meta-analysis establishing the cumulative incidence risk and the incidence density of infection in patients with multidrug-resistant Gram-negative bacteria (MDR-GNB) or vancomycin-resistant enterococci (VRE) colonisation of the gastrointestinal or urinary tract. 7 Willems RPJ van Dijk K Vehreschild MJGT et al. Incidence of infection with multidrug-resistant Gram-negative bacteria and vancomycin-resistant enterococci in carriers: a systematic review and meta-regression analysis. Lancet Infect Dis. 2022; (published online Jan 30.)https://doi.org/10.1016/S1473-3099(22)00811-8 Google Scholar Willems and colleagues pool aggregate results from 40 observational studies contributing 5015 VRE carriers and 9034 MDR-GNB carriers with a median study duration of 45 days (IQR 28–140). 7 Willems RPJ van Dijk K Vehreschild MJGT et al. Incidence of infection with multidrug-resistant Gram-negative bacteria and vancomycin-resistant enterococci in carriers: a systematic review and meta-regression analysis. Lancet Infect Dis. 2022; (published online Jan 30.)https://doi.org/10.1016/S1473-3099(22)00811-8 Google Scholar Infection and colonisation were as defined by the authors of each respective study and varied across studies. Incidence of infection with multidrug-resistant Gram-negative bacteria and vancomycin-resistant enterococci in carriers: a systematic review and meta-regression analysisThe risk of infection was substantial, with the highest risk for patients colonised with carbapenem-resistant Gram-negative bacteria and the lowest in patients with VRE. These data might help to guide prophylactic and treatment decisions and form a valuable resource for planning clinical trials on targeted prevention. Full-Text PDF

Extending outbreak investigation with machine learning and graph theory: Benefits of new tools with application to a nosocomial outbreak of a multidrug-resistant organism.

From January 1, 2018, until July 31, 2020, our hospital network experienced an outbreak of vancomycin-resistant enterococci (VRE). The goal of our study was to improve existing processes by applying machine-learning and graph-theoretical methods to a nosocomial outbreak investigation. We assembled medical records generated during the first 2 years of the outbreak period (January 2018 through December 2019). We identified risk factors for VRE colonization using standard statistical methods, and we extended these with a decision-tree machine-learning approach. We then elicited possible transmission pathways by detecting commonalities between VRE cases using a graph theoretical network analysis approach. We compared 560 VRE patients to 86,684 controls. Logistic models revealed predictors of VRE colonization as age (aOR, 1.4 (per 10 years), with 95% confidence interval [CI], 1.3-1.5; P < .001), ICU admission during stay (aOR, 1.5; 95% CI, 1.2-1.9; P < .001), Charlson comorbidity score (aOR, 1.1; 95% CI, 1.1-1.2; P < .001), the number of different prescribed antibiotics (aOR, 1.6; 95% CI, 1.5-1.7; P < .001), and the number of rooms the patient stayed in during their hospitalization(s) (aOR, 1.1; 95% CI, 1.1-1.2; P < .001). The decision-tree machine-learning method confirmed these findings. Graph network analysis established 3 main pathways by which the VRE cases were connected: healthcare personnel, medical devices, and patient rooms. We identified risk factors for being a VRE carrier, along with 3 important links with VRE (healthcare personnel, medical devices, patient rooms). Data science is likely to provide a better understanding of outbreaks, but interpretations require data maturity, and potential confounding factors must be considered.

Five-Year Survey of Asymptomatic Colonization with Multidrug-Resistant Organisms in a Romanian Tertiary Care Hospital.

PurposeTo determine the rate of carriage of multidrug-resistant organisms (MDROs) between 2015 and 2019 among patients admitted to the National Institute of Infectious Diseases “Prof. Dr. Matei Balș,” from Bucharest, Romania.MethodsNasal, throat, and rectal/perirectal screening swabs were collected either immediately or during the first 24 hours of admission and sent to the microbiology laboratory where the following MDROs were identified: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), extended-spectrum β-lactamase (ESBL)-producing Enterobacterales, carbapenem-resistant/carbapenemase-producing Enterobacterales (CRE/CPE), multidrug-resistant/extended drug-resistant Acinetobacter baumannii (MDR/XDR-AB), and multidrug-resistant/extended drug-resistant Pseudomonas aeruginosa (MDR/XDR-PA).ResultsA total of 5083 unique patients were screened for MRSA and 5008 for VRE, ESBL/CRE/CPE, MDR/XDR-AB, and MDR/XDR-PA. MRSA was detected in 8.24% of patients, VRE in 17.67%, ESBL Enterobacterales in 25.85%, and CPE in 6.13%. MDR/XDR-AB was found in 1.59% and MDR/XDR-PA in 1.91% of patients. The rates of carriage increased between 2015 and 2019 for MRSA (7.23–7.6%), VRE (9–16.68%), CPE (1.15–6.77%), MDR/XDR-PA (1.15–1.91%), and MDR/XDR-AB (1.15–2.04%). OXA-48-type carbapenemase was predominant in Klebsiella pneumoniae (68.62%) and Escherichia coli (89.47%). CPE bacteria other than Klebsiella pneumoniae and Escherichia coli identified in our study carried mostly metallo-beta-lactamase (n = 28, 84.85%).ConclusionIn this study, 37% of the unique patients screened over five years were found to be MDRO carriers. The proportion of VRE and CPE rectal carriers increased significantly between 2015 and 2019. The most frequently isolated carbapenemase was the OXA-48 type.

Vancomycin-resistant enterococcus bacteraemia in an endemic region: clinical features and genomic analysis: a 12-year cohort

Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens with increasing prevalence worldwide. Hospitals in Jerusalem, Israel are known to have high rates of VRE carriage. However, the clonicity of this pathogen in endemic areas remains unclear. The medical files of patients with VRE bacteraemia (N=182) hospitalized in the three major hospitals in Jerusalem between 2009 and 2020 were reviewed. These were compared with 100 patients with vancomycin-susceptible enterococcus (VSE) bacteraemia during the same period, and their clinical and demographic characters were analysed. Whole-genome sequencing (WGS) of the VRE isolates was performed, and the results were analysed considering the demographic, epidemiologic and clinical outcome data. Patients with VRE bacteraemia had higher rates of central line use, haematologic malignancy and immunosuppression compared with patients with VSE bacteraemia (63% vs 27%, P<0.001; 25% vs 13%, P=0.02; 24% vs 13%, P=0.04, respectively). Patients with VRE bacteraemia had significantly higher 7- and 30-day in-hospital mortality rates (31% vs 18%, P= 0.02; 57% vs 34%, P<0.001, respectively) and a longer mean hospital stay (39 vs 24 days, P=0.005) than patients with VSE bacteraemia. The WGS results of VRE isolates showed diversity rather than endemicity of a single clone. No clones were associated with specific ethnicity, geographical distribution or worse prognosis. WGS revealed the occurrence of small unrelated outbreaks rather than the expansion of large clusters in Jerusalem. VRE bacteraemia was found in sicker patients, and was associated with higher mortality and longer hospitalization compared with VSE bacteraemia.

Screening patients at admission to Copenhagen hospitals for carriage of resistant bacteria after contact with healthcare systems abroad, 2016–2019

ObjectivesPatients having previous contact with healthcare systems abroad are routinely screened for resistant bacteria on admission to hospitals in Copenhagen. This study aimed to present carriage prevalence and geographical risk stratification, as well as phenotypic and genotypic characterisation of resistant isolates. MethodsThis study included screening samples analysed at one department of clinical microbiology in Copenhagen from 2016–2019. Patients who had previous contact with healthcare systems abroad within 6 months were screened at admission for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE) and carbapenemase-producing organisms (CPO). Isolates were characterised phenotypically and by whole-genome sequencing. The relative frequency of positive findings stratified by geographical regions correlated with relative frequency of Danish residents’ travel destinations. ResultsOf 2849 screening sets included in the study, 103 (3.6%) were positive. A total of 120 resistant isolates were detected (36 MRSA, 31 VRE and 53 CPO). The carrier prevalence for MRSA was 1.3%, 1.1% for VRE and 1.5% for CPO. Southern and Western Asia were overrepresented travel destinations in positive screening sets (41%). For VRE, 40% were related to Southern Europe, which also represented 35% of travel destinations. Genotypic characterisation confirmed a heterogenous genomic background reflecting global distribution of resistant clones. ConclusionsExposure targeted screening identified a substantial number of asymptomatic carriers of MRSA, VRE and CPO with heterogenous genetic backgrounds. Although some geographical regions were overrepresented, the complex epidemiology of the different pathogens did not allow a restriction of the screening strategy to certain geographical regions.

Epidemiology and Transmission of Carbapenemase-Producing Enterobacteriaceae in a Health Care Network of an Acute-Care Hospital and Its Affiliated Intermediate- and Long-Term-Care Facilities in Singapore.

ABSTRACTMovement of patients in a health care network poses challenges for the control of carbapenemase-producing Enterobacteriaceae (CPE). We aimed to identify intra- and interfacility transmission events and facility type-specific risk factors of CPE in an acute-care hospital (ACH) and its intermediate-term and long-term-care facilities (ILTCFs). Serial cross-sectional studies were conducted in June and July of 2014 to 2016 to screen for CPE. Whole-genome sequencing was done to identify strain relatedness and CPE genes (blaIMI, blaIMP-1, blaKPC-2, blaNDM-1, and blaOXA-48). Multivariable logistic regression models, stratified by facility type, were used to determine independent risk factors. Of 5,357 patients, half (55%) were from the ACH. CPE prevalence was 1.3% in the ACH and 0.7% in ILTCFs (P = 0.029). After adjusting for sociodemographics, screening year, and facility type, the odds of CPE colonization increased significantly with a hospital stay of ≥3 weeks (adjusted odds ratio [aOR], 2.67; 95% confidence interval [CI], 1.17 to 6.05), penicillin use (aOR, 3.00; 95% CI, 1.05 to 8.56), proton pump inhibitor use (aOR, 3.20; 95% CI, 1.05 to 9.80), dementia (aOR, 3.42; 95% CI, 1.38 to 8.49), connective tissue disease (aOR, 5.10; 95% CI, 1.19 to 21.81), and prior carbapenem-resistant Enterobacteriaceae (CRE) carriage (aOR, 109.02; 95% CI, 28.47 to 417.44) in the ACH. For ILTCFs, presence of wounds (aOR, 5.30; 95% CI, 1.01 to 27.72), respiratory procedures (aOR, 4.97; 95% CI, 1.09 to 22.71), vancomycin-resistant enterococcus carriage (aOR, 16.42; 95% CI, 1.52 to 177.48), and CRE carriage (aOR, 758.30; 95% CI, 33.86 to 16,982.52) showed significant association. Genomic analysis revealed only possible intra-ACH transmission and no evidence for ACH-to-ILTCF transmission. Although CPE colonization was predominantly in the ACH, risk factors varied between facilities. Targeted screening and precautionary measures are warranted.

Prevalence and risk factors of colonisation with vancomycin-resistant Enterococci faecium upon admission to Germany's largest university hospital.

Background: Hospital-acquired infections due to vancomycin-resistant enterococci (VRE) are emerging globally. The aims of our study were to estimate VRE colonisation prevalence in patients upon admission, to determine possible risk factors for VR E. faecium acquisition that already exist in the outpatient setting, and to monitor whether VRE-colonised patients developed a VRE infection during their current hospital stay.Methods: In 2014 and 2015, patients admitted to non-intensive care units were screened for rectal VRE carriage. The study patients filled out a questionnaire on potential risk factors. Analyses were restricted to VR E. faecium carriage. All patients with VRE colonisation were retrospectively monitored for infections with VRE during their current hospital stay. Results: In 4,013 enrolled patients, the VRE colonisation prevalence upon admission was 1.2% (n=48), and colonisation prevalence was 1.1% (n=45) for VR E. faecium. Only one VRE-colonised patient developed an infection with the detection of a VRE, among others. Colonisation with VR E. faecium was associated with current antibiotic use. Risk factors of VR E. faecium colonisation upon admission were increasing age, previous colonisation or infection with multidrug resistant organisms, sampling year 2015, and, within the previous six months, antibiotic exposure, a stay at a rehabilitation center, and a hospital stay.Conclusions: We observed that antibiotic treatment which occurred prior admission influenced VR E. faecium prevalence upon admission. Thus, wise antibiotic use in outpatient settings plays a major role in the prevention of VR E. faecium acquisition.

Multidrug-Resistant Organism Carriage in Wisconsin Children

Background: Children attending daycare are at increased risk of carrying multidrug-resistant organisms (MDROs) compared to children not attending daycare. Carriage of MDROs greatly increases the risk of infection, not only in the child but also for others living in the household. Understanding the epidemiology of MDRO carriage in children is essential to devising effective containment strategies. Here, we present the findings from a cross-sectional study assessing MDRO carriage in daycare-attending and nonattending children in Wisconsin. Methods: We applied the following enrollment criteria: Children aged between 6 months and &lt;6 years and not enrolled in kindergarten; children who did not have an MDRO infection in the previous 6 months and did not receive any antimicrobials in the previous month; and children who did not have a gluten allergy, asthma, eczema, allergic rhinitis, cystic fibrosis, or an immunodeficiency. Children were enrolled by a parent or guardian who filled out a questionnaire on MDRO risk factor history and diet. Samples were collected from the nares, axilla or groin (pooled swab), and stool. Nasal samples were cultured for H. influenzae, S. pneumoniae, M. catarrhalis, and methicillin-resistant S. aureus (MRSA). Skin samples were cultured for MRSA, and stool samples were cultured for MRSA, C. difficile, vancomycin-resistant enterococci (VRE), and extended-spectrum β-lactamase–producing Gram-negative bacilli (ie, ESBL GNR). Results: In total, 44 children were enrolled in this study. The average age was 2.6 years and 50% were girls. Furthermore, 30 (68.2%) were identified by their parents as white, 9 (20.5%) as black, and 5 (11.3%) as other or multiracial. Incidentally, 23 children (52.3%) were enrolled in daycare. Overall, 18 children were positive for at least 1 organism, 9 of which had daycare exposure, and 5 children (1 in daycare) were positive for &gt;1 organism (11.4%). From stool samples, 6 children (13.6%, 2 in daycare) were C. difficile carriers, 3 were VRE carriers (6.8%, 1 in daycare), 8 carried an ESBL GNR (18.2%, 4 in daycare), and 3 carried MRSA (6.8%, 1 in daycare). One child was positive for H. influenzae (2.3%, not in daycare) and 2 were positive for S. pneumoniae (4.6%, 1 in daycare) from nares swabs. One child was positive for MRSA (2.3%, not in daycare) from a skin swab. We detected no significant differences between children with and without daycare exposure for any organism. Conclusions: Children in this population had higher than expected rates of ESBL GNRs and MRSA for a community population. Daycare exposure was not correlated with increased carriage in this small pilot study, though larger longitudinal studies are needed.Funding: NoneDisclosures: None

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.

Gastrointestinal Carriage of Vancomycin-Resistant Enterococci and Carbapenem-Resistant Gram-Negative Bacteria in an Endemic Setting: Prevalence, Risk Factors, and Outcomes.

Background: Gastrointestinal carriage of vancomycin-resistant enterococci (VRE) and carbapenem-resistant Gram-negative bacteria (CRGN) constitutes a major public health concern as it may be followed by clinical infection development or lead to intra-hospital dissemination. Detection of carriers and implementation of infection control measures are essential in every hospital. In this study we determined the point prevalence of VRE and CRGN in the fecal flora of the inpatients of a tertiary university hospital in Greece. We determined risk factors for carriage and examined the impact of carriage on hospital outcomes.Materials/Methods: A point prevalence study of VRE/CRGN rectal carriage of inpatients was conducted on March 2018. Specimens were selectively cultured for VRE/CRGN, microorganisms were biochemically identified, submitted to antibiotic susceptibility testing, and tested for carbapenemase production. Data on potential risk factors and hospital outcomes were collected at the time of culture and until hospital discharge. Multivariable logistic and linear regression models were used, adjusting for confounders.Results: Four hundred ninety-one patients were enrolled in the study. Of them, 64 (13.0%) were positive for VRE carriage, 40 (8.2%) for CRGN, and 10 patients (2.1%) for both VRE and CRGN. VRE carriage was independently associated with age over 65 years (adjusted OR: 2.4 [95%CI: 1.3, 4.5]) and length of stay (LOS) before rectal sampling (OR: 1.1 [95%CI: 1.0, 1.1]). Carriage of CRGN was associated with 11 days increase of LOS after rectal sampling (β-coef: 11.4 [95%CI: 1.6, 21.2]), with a 3.5-fold increased risk of acquiring a resistant pathogen after rectal swabbing (RR: 3.5 [95%CI 1.2, 9.9]) and with a 6-fold increased risk of mortality (RR: 6.1 [95%CI: 2.1, 17.9]), after adjusting for sex, age, and comorbidity index.Conclusions: High prevalence rates were found for VRE and CRGN carriage among the inpatients of our hospital. Prolonged hospitalization and age were independent risk factors for VRE carriage, while CRGN carriage was associated with increased risk of acquiring a resistant pathogen, prolonged hospital stay, and increased mortality.

Phenotypic and Genotypic Traits of Vancomycin-Resistant Enterococci from Healthy Food-Producing Animals.

Food-producing animals may be a reservoir of vancomycin-resistant enterococci (VRE), potentially posing a threat to animal and public health. The aims of this study were to estimate the faecal carriage of VRE among healthy cattle (n = 362), pigs (n = 350), sheep (n = 218), and poultry (n = 102 flocks) in Switzerland, and to characterise phenotypic and genotypic traits of the isolates. VRE were isolated from caecum content of six bovine, and 12 porcine samples respectively, and from pooled faecal matter collected from 16 poultry flock samples. All isolates harboured vanA. Three different types of Tn1546-like elements carrying the vanA operon were identified. Conjugal transfer of vanA to human Enterococcus faecalis strain JH2-2 was observed for porcine isolates only. Resistance to tetracycline and erythromycin was frequent among the isolates. Our data show that VRE harbouring vanA are present in healthy food-producing animals. The vanA gene from porcine isolates was transferable to other enterococci and these isolates might play a role in the dissemination of VRE in the food production chain.

Assessing the intestinal carriage rates of vancomycin-resistant enterococci (VRE) at a tertiary care hospital in Hungary

Excessive use of antibiotics contributes to the selection of resistant bacteria and intestinal colonization with multiresistant pathogens poses a risk factor for subsequent infections. The present study assessed vancomycin-resistant enterococci (VRE) carriage rates in patients admitted to our tertiary care hospital. Stool samples sent for routine culturing were screened with vancomycin containing solid or broth enrichment media. VRE isolates were identified with matrix-assisted laser desorption/ionization-time of flight mass spectrometry and antibiotic susceptibilities were tested by E-test. Vancomycin resistance genes were detected by polymerase chain reaction. Medical records of carriers were examined for suspected risk factors for colonization. Altogether 3025 stool specimens were analyzed. Solid media identified a VRE carriage rate of 2.2% while broth enrichment detected 5.8%. Seventy percent of the isolates were Enterococcus faecium. VanB genotype was detected in 38.2%, VanA in 37.3%, VanC1 in 22.6%, and VanC2 in 1.9%. All VRE were sensitive to linezolid, daptomycin, and tigecycline. Collective risk factors for carriage were diabetes, normal flora absence, Clostridioides difficile positivity, longer hospital stay, and advanced age. 78.5% of the carriers received antibiotic therapy which was metronidazole in most cases (47.3%). We recommend regular screening of risk groups such as patients with diabetes, history of recent hospitalization, or former C. difficile infection as an imperative step for preventing VRE dissemination.

2457. Data Science for Outbreak Investigation: Identifying Risk Factors, Tracing Contacts, and Eliciting Transmission Pathways in a Vancomycin-Resistant Enterococci (VRE) Outbreak

BackgroundIn 2018 we experienced a nosocomial outbreak due to vancomycin-resistant enterococci (VRE) in our hospital network. Our goals were to characterize risk factors for VRE acquisition, elicit potential hot spots of transmission, and delineate an optimized approach to tracing contacts.MethodsWe assembled diverse datasets of variable quality and covering different aspects of care from electronic medical records generated during the outbreak period (1/2018–9/2018). Patients who tested VRE-positive during this period were compared with controls with up to 3 negative screenings. First, we identified risk factors for VRE colonization by means of uni- and multivariate analyses. Next, we elicited transmission pathways by detecting commonalities between VRE cases, and determined whether patients with characteristics and connections similar to VRE cases were missed by our current contact tracing strategy.ResultsWe compared 221 VRE patients to 33,624 controls. Independent predictors of VRE colonization were ICU admission (OR 4.9, with 95% confidence interval [3.7–6.5], P < 0.001)], number of records in the database (a proxy for severity-of-illness, OR 1.1 [1.1–1.1], P < 0.001), length of hospital stay (OR 2.7 [2.0–3.5], P < 0.001), age (OR 1.3 [1.2–1.4], P < 0.001), and weeks of antibiotics (OR 1.2 [1.1–1.3], P < 0.001). By using complex network analysis, we were able to establish three main pathways by which the 221 VRE cases are connected: healthcare personnel, medical devices, and patient rooms. This multi-dimensional network extends beyond our current contact tracing strategy, which captures inpatients based on geographical proximity (cf. figure).ConclusionIn this outbreak investigation based on a large electronic healthcare data collection, we found three main risk factors for being a VRE carrier (ICU admission, length of hospital stay, antibiotic exposure), along with three important links between VRE cases (healthcare personnel, medical devices, patient rooms). Data science is likely to provide a better understanding of outbreaks, but interpretations should take data maturity, the scope of included sources, and potential confounding factors into account. Disclosures All authors: No reported disclosures.

Determining the clinical significance of co-colonization of vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus in the intestinal tracts of patients in intensive care units: a case\u2013control study

BackgroundThe emergence of vancomycin-resistant Staphylococcus aureus (VRSA) has become a global concern for public health. The proximity of vancomycin-resistant enterococcus (VRE) and methicillin-resistant S. aureus (MRSA) is considered to be one of the foremost risk factors for the development of VRSA. This study aimed to determine the incidence, risk factors, and clinical outcomes of intestinal co-colonization with VRE and MRSA.MethodsA case–control study was conducted in 52-bed intensive care units (ICUs) of a university-affiliated hospital from September 2012 to October 2017. Active surveillance using rectal cultures for VRE were conducted at ICU admission and on a weekly basis. Weekly surveillance cultures for detection of rectal MRSA were also conducted in patients with VRE carriage. Patients with intestinal co-colonization of VRE and MRSA were compared with randomly selected control patients with VRE colonization alone (1:1). Vancomycin minimum inhibitory concentrations (MICs) for MRSA isolates were determined by the Etest.ResultsOf the 4679 consecutive patients, 195 cases and 924 controls were detected. The median monthly incidence and duration of intestinal co-colonization with VRE and MRSA were 2.3/1000 patient-days and 7 days, respectively. The frequency of both MRSA infections and mortality attributable to MRSA were higher in the case group than in the control group: 56.9% vs. 44.1% (P = 0.011) and 8.2% vs. 1.0% (P = 0.002), respectively. Independent risk factors for intestinal co-colonization were enteral tube feeding (odds ratio [OR], 2.09; 95% confidence interval [CI] 1.32–3.32), metabolic diseases (OR, 1.75; 95% CI 1.05–2.93), male gender (OR, 1.62; 95% CI 1.06–2.50), and Charlson comorbidity index < 3 (OR, 3.61; 95% CI 1.88–6.94). All MRSA isolates from case patients were susceptible to vancomycin (MIC ≤ 2 mg/L).ConclusionsOur study indicates that intestinal co-colonization of VRE and MRSA occurs commonly among patients in the ICU with MRSA endemicity, which might be associated with poor clinical outcomes.

Risk Factors for Long-Term Vancomycin-Resistant Enterococci Persistence-A Prospective Longitudinal Study.

Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens that require effective infection control measures, representing a challenge for healthcare systems. This study aimed at identifying risk factors associated with prolonged VRE carriage and determining the rate of clearance that allows the discontinuation of contact precautions. During a 2-year study, screening was performed in patients with a history of VRE or at risk of becoming colonized. After bacterial identification and antibiotic susceptibility testing, glycopeptide resistance was confirmed by PCR. Isolates were compared via whole genome sequence-based typing. Risk factors were recorded, and follow-up screening was performed upon readmission, defining patients as long-term carriers if still colonized ≥10 weeks after first detection. Of 1059 patients positive for VRE, carriage status was assessed upon readmission in 463 patients. VRE was cleared in 56.4% of the cases. Risk factors associated with long-term persistence were hospital stays (frequency, length), hemato-oncological disease, systemic treatment with steroids, and use of antibiotics. No specific genotypic clustering was observed in patients with VRE clearance or persistence. VRE clearance is possibly underestimated. The identification of risk factors favoring long-term carriage may contribute to a targeted implementation of infection control measures upon readmission of patients with history of VRE.

High prevalence of multidrug resistant Enterobacteriaceae among residents of long term care facilities in Amsterdam, the Netherlands.

IntroductionThe aim of this study was to determine the rate of asymptomatic carriage and spread of multidrug-resistant micro-organisms (MDRO) and to identify risk factors for extended spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) carriage in 12 long term care facilities (LTCFs) in Amsterdam, the Netherlands.Materials and methodsFrom November 2014 to august 2015, feces and nasal swabs from residents from LTCFs in Amsterdam, the Netherlands were collected and analyzed for presence of multidrug-resistant Gram-negative bacteria (MDRGN), including ESBL-E, carbapenemase-producing Enterobacteriaceae (CPE), colistin-resistant Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Logistic regression analysis was performed to assess associations between variables and ESBL-carriage.ResultsIn total, 385 residents from 12 LTCFs (range 15–48 residents per LTCF) were enrolled. The prevalence of carriage of MDRGN was 18.2% (range among LTCFs 0–47%) and the prevalence of ESBL-E alone was 14.5% (range among LTCFs: 0–34%). Of 63 MDRGN positive residents, 50 (79%) were ESBL-E positive of which 43 (86%) produced CTX-M. Among 44 residents with ESBL-E positive fecal samples of whom data on contact precautions were available at the time of sampling, only 9 (20%) were already known as ESBL-E carriers. The prevalence for carriage of MRSA was 0.8% (range per LTCF: 0–7%) and VRE 0%. One CPE colonized resident was found. All fecal samples tested negative for presence of plasmid mediated resistance for colistin (MCR-1). Typing of isolates by Amplified Fragment Length Polymorphism (AFLP) showed five MDRGN clusters, of which one was found in multiple LTCFs and four were found in single LTCFs, suggesting transmission within and between LTCFs. In multivariate analysis only the presence of MDRO in the preceding year remained a risk factor for ESBL-E carriage.ConclusionsThe ESBL-carriage rate of residents in LTCFs is nearly two times higher than in the general population but varies considerably among LTCFs in Amsterdam, whereas carriage of MRSA and VRE is low. The majority (80%) of ESBL-E positive residents had not been detected by routine culture of clinical specimens at time of sampling. Current infection control practices in LTCFs in Amsterdam do not prevent transmission. Both improvement of basic hygiene, and funding for laboratory screening, should allow LTCFs in Amsterdam to develop standards of care to prevent transmission of ESBL-E.