Long-term carriage of vancomycin-resistant enterococci in patients discharged from hospitals: a 12-year retrospective cohort study.

Contact precautions are recommended in hospitals to prevent the transmission of vancomycin-resistant enterococci (VRE); however, there is no clear policy for how long patients should be under contact precautions due to a lack of information on the duration of carriage of these organisms. We conducted a retrospective cohort study to understand the duration of carriage of VRE (by screening of a single stool culture) and associated factors among patients who had been identified with VRE infection and/or colonization since the year 2000 at our health facilities. Of the 345 eligible participants, 136 did not respond, 90 declined to participate, and 16 did not send in the required specimens. Of the 103 remaining participants, 13 were found to have current VRE fecal carriage. The proportion of colonized patients fell from 40% (2/5) in the first year to 23.3% (7/30) in year 4. None of the 40 patients who had VRE detected >4 years prior were found to be colonized at the time of the study. The longest duration of detected VRE positivity was 46.5 months. Univariate analysis revealed that recent exposure to any antibiotics (P = 0.016), multiple antibiotics (P = 0.001), amoxicillin-clavulanic acid (P = 0.021), piperacillin-tazobactam (P = 0.007), glycopeptides (P < 0.001), meropenem (P = 0.007), aminoglycosides (P = 0.021), or fluoroquinolones (P = 0.021), being the index case in a clinical specimen (P = 0.016), and recent hospitalization (P < 0.001) were significantly associated with continued carriage on follow-up. In the surviving outpatients, a significant proportion appeared to clear VRE carriage. Our results suggest that in the absence of recent risk factors, such as hospitalization or antibiotic use, patients with a remote history of colonization (>4 years) may no longer require contact isolation precautions.

Impact of chlorhexidine-impregnated washcloths on reducing incidence of vancomycin-resistant enterococci colonization in hematology-oncology patients.

BACKGROUND: Daily skin cleansing with washcloths impregnated with chlorhexidine gluconate (CHG) of patients in intensive care unit is associated with reduction in incidence of vancomycin-resistant Enterococci (VRE) acquisition. This study describes the impact on incidence of VRE colonization after the implementation of daily skin cleansing with 2% CHG-impregnated washcloths in hematology-oncology patients. METHODS: In this before-and-after study, we compared the incidence rate of VRE colonization during the baseline period (where routine soap-and-water bathing was used) with the intervention period where patients were cleansed with 2% CHG-impregnated washcloths. RESULTS: Acquisition of VRE decreased from 7.8% in the baseline to 3.8% in the intervention period (relative risk, 0.48, 95% confidence interval [CI], 0.21-1.09; P = .07). The crude relative rate of acquisition during the intervention period compared with the baseline period was 0.53 (95% CI, 0.23-1.23; P = .13). Patients who had been a roommate of a patient subsequently found to have VRE were at a significantly increased risk for acquiring VRE (hazard ratio, 18.8, 95% CI, 5.37-66.15; P < .001). However, patients admitted to the same bed number of previously known VRE-colonized patient were not at increased risk of VRE acquisition (hazard ratio, 0.37, 95% CI, 0.11-1.22; P = .10). CONCLUSION: We did not observe a statistically significant reduction in the rate of VRE colonization in association with the use of 2% CHG-impregnated washcloths among hematology-oncology patients.

Prevalence and risk factors for VRE colonisation in a tertiary hospital in Melbourne, Australia: a cross sectional study.

BACKGROUND: Vancomycin-resistant Enterococcus (VRE) has been established as a significant health-care associated problem since its first isolation in Australia in 1994. In this study, we measured the point prevalence and identified risk factors associated with vanB VRE colonisation in a tertiary care hospital in Melbourne, Australia where VRE has been endemic for 15 years. METHODS: A hospital-wide point prevalence survey was conducted on October 13, 2008 with colonisation detected using rectal swab culture. Patient's demographic and medical information was collected through a review of medical records. Factors associated with VRE colonisation in univariate analysis were included in multivariate logistic regression model to adjust for confounding. RESULTS: The prevalence of VRE colonisation on the day of screening was 17.5% (95% CI, 13.7 to 21.9). VRE was detected from patients in each ward with the prevalence ranging from 3% to 29%. Univariate analysis showed the use of any antibiotic, meropenem, ciprofloxacin, diarrhoea and longer length of hospital stay were associated with increased risk of VRE colonisation (p<0.05). However, age, sex, proximity to VRE positive cases, use of other antibiotics including cephalosporins, vancomycin were not associated with increased risk (P>0.05). Multivariate analysis showed the exposure to meropenem (p=0.004), age (≥65 years) (p=0.036) and length of stay ≥7 days (p<0.001) as independent predictors of VRE colonisation. CONCLUSION: Our study suggests that exposure to antibiotics may have been more important than recent cross transmission for a high prevalence of vanB VRE colonisation at our hospital.

Reduction in hospitalwide incidence of infection or colonization with methicillin-resistant Staphylococcus aureus with use of antimicrobial hand-hygiene gel and statistical process control charts.

OBJECTIVE: To evaluate the impact of serial interventions on the incidence of methicillin-resistant Staphylococcus aureus (MRSA). DESIGN: Longitudinal observational study before and after interventions. SETTING: The Alfred Hospital is a 350-bed tertiary referral hospital with a 35-bed intensive care unit (ICU). INTERVENTIONS: A series of interventions including the introduction of an antimicrobial hand-hygiene gel to the intensive care unit and a hospitalwide MRSA surveillance feedback program that used statistical process control charts but not active surveillance cultures. METHODS: Serial interventions were introduced between January 2003 and May 2006. The incidence and rates of new patients colonized or infected with MRSA and episodes of MRSA bacteremia in the intensive care unit and hospitalwide were compared between the preintervention and intervention periods. Segmented regression analysis was used to calculate the percentage reduction in new patients with MRSA and in episodes of MRSA bacteremia hospitalwide in the intervention period. RESULTS: The rate of new patients with MRSA in the ICU was 6.7 cases per 100 patient admissions in the intervention period, compared with 9.3 cases per 100 patient admissions in the preintervention period (P=.047). The hospitalwide rate of new patients with MRSA was 1.7 cases per 100 patient admissions in the intervention period, compared with 3.0 cases per 100 patient admissions in the preintervention period (P<.001). By use of segmented regression analysis, the maximum and conservative estimates for percentage reduction in the rate of new patients with MRSA were 79.5% and 42.0%, respectively, and the maximum and conservative estimates for percentage reduction in the rate of episodes of MRSA bacteremia were 87.4% and 39.0%, respectively. CONCLUSION: A sustained reduction in the number of new patients with MRSA colonization or infection has been demonstrated using minimal resources and a limited number of interventions.