Prevalence Of Vancomycin-resistant Enterococci Colonization Research Articles

Transmission dynamics of a linear vanA-plasmid during a nosocomial multiclonal outbreak of vancomycin-resistant enterococci in a non-endemic area, Japan

The spread of vancomycin-resistant enterococci (VRE) is a major threat in nosocomial settings. A large-scale multiclonal VRE outbreak has rarely been reported in Japan due to low VRE prevalence. We evaluated the transmission of vancomycin resistance in a multiclonal VRE outbreak, conducted biological and genomic analyses of VRE isolates, and assessed the implemented infection control measures. In total, 149 patients harboring VanA-type VRE were identified from April 2017 to October 2019, with 153 vancomycin-resistant Enterococcus faecium isolated being grouped into 31 pulsotypes using pulsed-field gel electrophoresis, wherein six sequence types belonged to clonal complex 17. Epidemic clones varied throughout the outbreak; however, they all carried vanA-plasmids (pIHVA). pIHVA is a linear plasmid, carrying a unique structural Tn1546 containing vanA; it moves between different Enterococcus spp. by genetic rearrangements. VRE infection incidence among patients in the “hot spot” ward correlated with the local VRE colonization prevalence. Local prevalence also correlated with vancomycin usage in the ward. Transmission of a novel transferrable vanA-plasmid among Enterococcus spp. resulted in genomic diversity in VRE in a non-endemic setting. The prevalence of VRE colonization and vancomycin usage at the ward level may serve as VRE cross-transmission indicators in non-intensive care units for outbreak control.

Clinical Outcome of Vancomycin-Resistant Enterococcus Colonization Among Liver Transplant Recipients at Shiraz Organ Transplant Center.

Liver transplant recipients are more susceptible to vancomycin-resistant enterococci colonization than healthy individuals. We investigated the prevalence of vancomycin-resistant enterococci colonization and its effect on the outcomes of liver transplant recipients. Patients who had undergone primary liver transplant at the Shiraz Organ Transplant Center from 2015 to 2017 were enrolled in this study. Demographic characteristics, laboratory test results, duration of stay in the intensive care unit, total duration of hospital stay, and clinical outcome data were extracted from the Shiraz Organ Transplant Center database. Posttransplant outcomes such as graft rejection, mortality, hospital stay, and kidney function tests were included for the first 90 days after transplant. A total of 753 liver transplant recipients (470 males and 283 females) were included in this study. Vancomycin-resistant enterococci colonization was identified in 51 patients (6.8%) after transplant at the time of intensive care unit admission. Our study found no significant difference between outcomes for patients with vancomycin-resistant enterococci colonization and outcomes for patients without colonization, including graft rejection, mortality, hospital stay, and kidney function tests. Our study revealed that asymptomatic vancomycin-resistant enterococci colonization in liver transplant patients has no adverse effect on the duration of posttransplant hospital stay, early mortality rate, graft rejection rate, or kidney function compared with noncolonized patients.

Vancomycin-resistant enterococci carriage in an acute Irish hospital

Ireland has been shown to have the highest rate of vancomycin-resistant enterococci (VRE) in cases of bacteraemia in Europe, according to a report in 2014 from the European Antimicrobial Resistance Surveillance System Network. To investigate the prevalence of VRE gut colonization in a cohort of patients in 2014 at Cork University Hospital (CUH) by performing a cross-sectional study using faecal samples submitted to the microbiology laboratory for routine investigation from both hospital inpatients and community-based patients. Faeces were examined for VRE colonization using selective cultivation, antimicrobial susceptibility testing, and speciation using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. All VRE isolates were evaluated by molecular means for resistance determinants, type, and Insertion Sequence 16 as an indicator of Clonal Complex 17 (CC17). From the 350 specimens investigated, 67 (19.1%) specimens were positive for VRE [95% confidence interval (CI): 15.0-23.2]. The prevalence of VRE colonization among CUH patients tested in this study (N=194) was 31.4% (95% CI: 24.7-38.1). By contrast, the general practitioner patient samples (N=29) showed a prevalence of 0%, whereas 22.2% of samples from other hospitals (N=27) were positive for VRE. All isolates were Enterococcus faecium (VREfm) and were indicated to contain CC17, though with considerable heterogeneity among the isolates. This high prevalence goes some way towards providing an explanation for the current high rates of VRE bacteraemia in Ireland, as well as highlighting the benefits of screening and enhanced infection control practices by all hospitals to control the high rates of VRE observed.

Prevalence of Vancomycin-resistant Enterococci Colonization, and Susceptibility to linezolid in Pediatric Intensive Care Units of a Referral Pediatric Center in Tehran, Iran

Background:: Vancomycin-resistant Enterococcus (VRE) has been established as a significant health-care associated problem, and caused significant morbidity and mortality. Objectives:: This study was aimed to determine prevalence of VRE colonization in severely ill patients admitted to Pediatric Intensive Care Unit (PICU), and identify potential risk factors for colonization, and in vitro susceptibility of VRE to linezolid. Patients and Methods:: Rectal swabs were taken from 71 children 18 years old or younger who were admitted with serious systemic illness, including malignancy, chronic kidney, lung or liver diseases, treatment with chemotherapeutic agents, immunodeficiency, treatment with high-dose corticosteroids, malnutrition, previous treatment with 2nd or 3rd generation cephalosporin, aminoglycoside, and broad-spectrum β-lactam antibiotics within the past 3 months. Demographics and known risk factors were retrieved and assessed by statistical methods. Results:: A total of 71 patients with a mean age of 29.1 ± 38.5 months were enrolled in this study. The prevalence of VRE rectal colonization was 66.2%. None of the potential risk factors including age, gender, comorbidities, previous admission into ICU, length of stay in ICU, presence of invasive devices were significantly associated with VRE colonization. Linezolid-susceptible isolated strains accounted 97.9%. Conclusions:: The prevalence of VRE was higher compared to previous reports from local and international studies. In order to control the spread of VRE, appropriate use of antibiotics, adherence to infection control measures, and shortening the duration of ICU stay is highly recommended.

Healthcare-Associated Risk Factors of Vancomycin-Resistant Enterococci Colonization among Outpatients Undergoing Hemodialysis

Stool specimens and data were obtained from 399 outpatients undergoing hemodialysis (HD) in order to estimate the colonization rate of vancomycin-resistant enterococci (VRE) and to determine risk factors for VRE acquisition. The prevalence of VRE colonization in outpatients ranged from 0%-22.2%. Risk factors associated with VRE colonization were high hierarchy of hospital, short duration of HD, recent hospitalization, prior use of antimicrobial products, high platelet count, and low hemoglobin/albumin/blood urea nitrogen/creatinine levels, showing that VRE colonization was more common in patients with prior infections and poor nutritional status. Although pulsed-field gel electrophoresis (PFGE) analysis showed that most VRE isolates had diverse patterns, 2 paired cases from separate hospitals presented identical PFGE types.

Epidemiology of vancomycin-resistant enterococci in children with acute lymphoblastic leukemia at two referral centers in Tehran, Iran: a descriptive study

Risk factors for colonization with vancomycin-resistant enterococci (VRE) vary by population and locale. The objective of this study was to determine the prevalence of and risk factors for VRE colonization in children with acute lymphoblastic leukemia (ALL) in Tehran. Stools were collected from children with ALL at the Ali Asghar Children's Hospital and the Mahak Pediatric Oncology Center between March 2007 and October 2008. Demographic features and potential risk factors for VRE colonization, including duration of ALL, presence of severe neutropenia in the preceding month, receipt of antibiotics in the preceding 3 months, concurrent medical problems, days of hospitalization, and the need for intensive care since the time of diagnosis of ALL, were recorded. VRE was identified from stools in 33 of 130 children with ALL (25%). No clear risk factors were identified for VRE colonization in the current study, but there was a trend towards an increased prevalence in children admitted to the intensive care unit since their ALL diagnosis (p=0.07). The VanA genotype was found in 28 of the 33 stools (85%), with all other enterococci being VanB. The prevalence of VRE colonization in children with ALL in Tehran is high. Modifiable risk factors have not been identified. The implementation of routine surveillance for colonization and an increased emphasis on adherence to standard infection control precautions may prevent spread.

Epidemiology of Vancomycin-Resistant Enterococci Among Patients on an Adult Stem Cell Transplant Unit: Observations From an Active Surveillance Program

To use the findings of an active surveillance program to delineate the unique epidemiology of vancomycin-resistant enterococci (VRE) in a mixed population of transplant and nontransplant patients hospitalized on a single patient care unit. Surveillance survey and case-control analysis. A 19-bed adult bone marrow and stem cell transplant unit at a referral and primary-care center. The study included patients undergoing transplantation, patients who had previously received bone marrow or stem cell transplants, and patients with other malignancies and hematological disorders who were admitted to the study unit. Patients not previously identified as colonized with VRE had perirectal swab specimens collected at admission and once weekly while hospitalized on the unit. The prevalence of VRE colonization at admission and the incidence throughout the hospital stay, genotypes of VRE specimens as determined by pulsed field gel electrophoresis, and risk factors related to colonization were analyzed. There was no significant difference in the prevalence or incidence of new colonization between nontransplant patients and prior or current transplant recipients, although overall prevalence at admission was significantly higher in the prior transplant group. Preliminary genotypic analysis of VRE isolates from transplant patients suggests that a proportion of cases of newly detected VRE carriage may represent prior colonization not detected at admission, with different risk factors suggestive of a potential epidemiological distinction. Examination of epidemiological and microbiological data collected by an active surveillance program provides useful information about the epidemiology of VRE that can be applied to inform rational infection control strategies.

Prevalence of Vancomycin-Resistant Enterococci colonization and its risk factors in chronic hemodialysis patients in Shiraz, Iran

BackgroundVancomycin-resistant entrococci (VRE) are increasing in prevalence at many institutions, and are often reported in dialysis patients. The aim of this cross-sectional prevalence study was to determine the prevalence and risk factors of VRE colonization in chronic hemodialysis patients in two hemodialysis centers in Shiraz, Iran.MethodsRectal swabs were obtained from all consenting patients and were streaked on the surface of Cephalexin-aztreonam-arabinose agar (CAA) and incubated at 37°C in air for 24 h. The vancomycin susceptibility of each isolate was confirmed by disk susceptibility testing. The MICs of vancomycin and teicoplanin were confirmed by the E test. To identify risk factors, a questionnaire was completed for all the studied patients and the data of VRE positive and negative groups were compared using Man-Withney U test for continues data and the Fisher exact test for categorical data.ResultsOf 146 patients investigated, 9 (6.2%) were positive for VRE. All VRE strains were genotypically distinguishable. Risk factors for a VRE-positive culture were "antimicrobial receipt within 2 months before culture" (P = 0.003) and "hospitalization during previous year" (P = 0.016).ConclusionVRE colonization is an under-recognized problem among chronic dialysis patients in Iran. VRE colonization is associated with antibiotic consumption and hospitalization.

Vancomycin-Resistant Enterococcus (VRE) Colonization Is Associated with a High Rate of Bacteremia and Early Mortality in Transplant/Leukemia Patients.

Background: Vancomycin-resistant enterococci (VRE) have become increasingly important nosocomial pathogens in very ill and immunocompromised hospitalized patients (pts). Due to an increase in VRE clinical cultures including bacteremias on our institutional transplant/leukemia service in early 2004, active surveillance for VRE among this population was instituted in June 2004. We describe here the incidence and prevalence of VRE colonization and infection in this population over a two year study period, as well as selected pt demographics and mortality associated with VRE bacteremia.Methods: Between June 2004 and July 2006, active surveillance for VRE on inpatients on the transplant/leukemia service was performed by acquiring perirectal or stool swabs for VRE culture on hospital admission and on a weekly basis while inpatient. Acquisition of VRE was determined to be nosocomial if the initial culture was negative followed by a positive culture at any time during the hospital stay. Multiple sequential interventions as recommended by the Society for Healthcare and Epidemiology (SHEA) guidelines were implemented. Pt census data and daily isolation indicators were used to help determine VRE colonization rates and the prevalence of VRE on the units. Chart reviews were performed to obtain information on clinical pts related features and mortality of bacteremic pts.Results: Nineteen percent (193/1019) of pts screened were colonized with VRE with the monthly nosocomial colonization rate ranging from 2–12% (rate/1000 patient days). Eighteen percent (31/189) of pts newly colonized with VRE became bacteremic, including 7/31 who had bacteremia as their primary presentation. Of the bacteremic pts, 24 (77.4%) died at a median of 20 days (range 2–208 days), 18 (75%) dying during their bacteremic hospitalization of multiple causes. Sixteen had acute leukemia, 11 non-Hodgkin's lymphoma, and 3 other malignancies. Eighteen bacteremic pts had undergone allogeneic transplant & 5 autologous transplant. Fourteen of 18 allogeneic transplant pts had active GVHD and all 18 were on immune suppression therapy. Of all allogeneic transplants performed during the study period, 13% (18/140) were complicated by VRE bacteremia. Sixteen bacteremic pts required ICU stays, while 6 had C. difficile colitis and 5 mucositis during the same hospital stay. SHEA recommended interventions instituted at various times (e.g. enhanced contact and barrier precautions for colonized pts, “supercleans” of unit, written communication to staff, pts and families, gloving for all pt contacts) did not have a durable effect on these rates. However, the ratio of new nosocomial cases/overall prevalence of VRE in the units decreased 20% over the study period, suggesting some measure of control despite high colonization pressure. Assessment of response to intensive control strategies as well as delineation of risk factors for bacteremia and death in this population are ongoing and will be presented.Conclusion: Despite application of standardized guidelines for VRE control, affecting a marked and durable decrease in endemic VRE colonization on a complicated transplant/leukemia service is difficult. VRE bacteremia following colonization in transplant/leukemia pts is common and is associated with early mortality. VRE control remains critical, and new modalities and approaches are essential.

Prospective surveillance of vancomycin-resistant enterococci in a neonatal intensive care unit.

A point-prevalence study of vancomycin-resistant enterococci colonization of the gastrointestinal tract in an Israeli hospital revealed that 14.7% of the 320 inpatients were colonized. Vancomycin-resistant enterococci colonization was detected in most departments except the neonatal intensive care unit. Hence, a prospective longitudinal study of the prevalence of vancomycin-resistant enterococci colonization in the neonatal intensive care unit was conducted. A rectal swab was obtained from every newborn on admission to the neonatal intensive care unit and once weekly thereafter until the patient was discharged. Enterococci were isolated and tested for susceptibility to vancomycin. A total of 84 neonates were enrolled and monitored on average for 3 weeks (SD +/- 3.9, range 1-20 weeks). Mean gestational age was 35.7 weeks (SD +/- 3.9, range 25-42 weeks), and mean birth weight was 2.4 kg (SD +/- 0.9, range 0.45-4.1 kg). Most patients had one or more of the known risk factors associated with colonization with vancomycin-resistant enterococci. Eighty percent of the patients received antibiotics during the study, and 14.3% received vancomycin. The median duration of vancomycin treatment was 12.5 days (SD +/- 16.8, range 5-55 days). Fifty-one of 84 (61%) patients acquired enterococci sensitive to vancomycin during the study period, but no newborn had vancomycin-resistant enterococci. Possible explanations for this finding may be physical isolation of the neonatal intensive care unit from the rest of the hospital, intrinsic differences in the bowel milieu of this age group and the lack of exposure to food and other environmental sources of vancomycin-resistant enterococci from the community.