Extended spectrum beta-lactamase producing Enterobacterales faecal carriage in a medical intensive care unit: low rates of cross-transmission and infection.

Background: Extended-spectrum beta-lactamases-producing Enterobacterales (ESBL-E) are disseminating worldwide especially in Intensive Care Units (ICUs) and are responsible for increased health costs and mortality. The aims of this work were to study ESBL-E dissemination in ICU and to assess the impact of ESBL-E fecal carriage on subsequent infections during a non-outbreak situation. Methods: We therefore screened every patient at admission then once a week in a medical ICU between January and June 2015. Each ESBL-E isolate was characterized by ESBL genes PCR amplification and the clonal dissemination was assessed by Pulsed-Field Gel Electrophoresis (PFGE). Results: Among the 608 screened patients, 55 (9%) were colonized by ESBL-E. Forty-four isolates were available for further analysis. Most of them (43/44, 98%) contained a ESBL gene from the CTX-M group. Only one case of ESBL-E cross-transmission occurred, even for acquired ESBL-E colonization. Subsequent infection by ESBL-E occurred in 6/55 (11%) patients and infecting ESBL-E strains were the colonizing ones. ESBL-E faecal carriage had a negative predictive value of 100% and a positive predictive value of 40% to predict ESBL-E ventilator associated-pneumonia (VAP). Alternatives to carbapenems consisting in piperacillin-tazobactam, ceftolozane-tazobactam and ceftazidime-avibactam were all active on this panel of ESBL-E. Conclusions: ESBL-E expansion and acquisition in ICU in a non-outbreak situation are not any more fully explained by cross-transmission. Mechanisms underlying ESBL-E dissemination in ICU are still to investigate. Interestingly, as far as we know, our study demonstrates for the first time by PFGE that the colonizing strain is indeed the infecting one in case of subsequent ESBL-E infection. Nevertheless, subsequent ESBL-E infection remains a rare event conferring poor positive predictive value for ESBL-E colonization to predict ESBL-E VAP. Relevance of systematic ESBL-E faecal screening at ICU admission and during ICU stay needs further investigation.

Is systematic fecal carriage screening of extended-spectrum beta-lactamase-producing Enterobacteriaceae still useful in intensive care unit: a systematic review.

BACKGROUND: Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are disseminating worldwide leading to increased hospital length of stay and mortality in intensive care units (ICU). ESBL-E dissemination was first due to outbreaks in hospital settings which led to the implementation of systematic fecal carriage screening to improve hygiene procedures by contact precautions. ESBLs have since spread in the community, and the relevance of contact precautions is questioned. ESBL-E dissemination led to an overuse of carbapenems triggering the emergence of carbapenem-resistant Enterobacteriaceae. Empirical antimicrobial therapy based on ESBL-E fecal carriage has been proposed but is debated as it could increase the consumption of carbapenems among ESBL-E carriers without any clinical benefit. Finally, selective decontamination among ESBL-E fecal carriers is evoked to decrease the risk for subsequent ESBL-E infection, but its efficacy remains debated. We propose to systematically review the evidence to recommend or not such systematic ESBL-E fecal carriage screening in adult ICU. METHODS: Every article focusing on ESBL-E and ICU available on the MEDLINE database was assessed. Articles were included if focusing on cross-transmission, efficacy of hygiene procedures, link between ESBL-E colonization and infection or guidance of empirical therapy or selective decontamination efficacy. RESULTS: Among 330 articles referenced on PubMed, 39 abstracts were selected for full-text assessment and 25 studies were included. Systematic screening of ESBL-E fecal carriage to guide contact precautions do not seem to decrease the rate of ESBL-E cross-transmission. It has a very good negative predictive value for subsequent ESBL-E infections but a positive predictive value between 40 and 50% and so does not help to spare carbapenems. Cessation of ESBL-E carriage systematic screening could decrease the use of carbapenems in ICU without any clinical harm. Nevertheless, further studies are needed to validate these results from monocentric before-after study. Selective decontamination strategy applied to ESBL-E fecal carriers could be helpful, but available data are conflicting. CONCLUSION: Current knowledge lacks of high-quality evidence to strongly recommend in favor of or against a systematic ESBL-E fecal carriage screening policy for ICU patients in a non-outbreak situation. Further evaluation of selective decontamination or fecal microbiota transplantation among ESBL-E fecal carriers is needed.

Control of extended-spectrum ß-lactamase-producing Enterobacteriaceae nosocomial acquisition in an intensive care unit: A time series regression analysis.

BACKGROUND: This study was undertaken to determine the temporal relationship between implementation of different interventions in an intensive care unit (ICU) and control of endemic nosocomial acquisition of extended-spectrum ß-lactamase Enterobacteriaceae (ESBLE). METHODS: This was a prospective observational study with time-series analysis of the monthly incidence of ESBLE and its predictors. In November 2007, after a 14-month baseline period, an intervention consisting of restriction of third-generation cephalosporins (3 GC) and increased use of alcohol-based hand rubs was implemented. In January 2008, an increased health care worker (HCW):patient ratio was also implemented. In March 2010, the ICU was closed, and patients were moved to a clean ICU. RESULTS: The first intervention resulted in global reduction in 3 GC and increased use of alcohol-based hand rub. A significant change in ESBLE incidence was observed in a full segmented univariate regression analysis (mean change in level, -0.91 ± 0.19; P < .0001). After ICU closure, there was a dramatic reduction in ESBLE acquisition. According to the multivariate model, the ICU closure was the main protective factor. Before ICU closure, an increase in the HCW:patient ratio of 0.1 point tended to be associated with a decreased risk of ESBLE acquisition (relative risk, 0.28; 95% confidence interval, 0.06-1.25; P = .09). CONCLUSIONS: This study shows that ICU closure was associated with, but not necessarily the reason for, control of ESBLE cross-transmission in a nonoutbreak setting. Environmental ESBE sources may play a role in cross-transmission.

Influence of amoebae and physical and chemical characteristics of water on presence and proliferation of Legionella species in hospital water systems.

The reservoir for hospital-acquired Legionnaires' disease has been shown to be the potable water distribution system. The objectives of the present study were as follows: (1) to examine the possible relationship between physical-chemical characteristics of water such as temperature, pH, hardness, conductivity, and residual chlorine and the presence of amoebae as growth-promoting factors for Legionella species and (2) to determine eradication measures for water distribution systems to seek ways of reducing the risk of legionellosis. Ten hospitals in southwest France took part in this study. Water samples were collected from 106 hot water faucets, showers, hot water tanks, and cooling towers. Two analyses were performed to analyze the association between water characteristics and (1) the presence of Legionella species and (2) the proliferation of Legionella species. Of the 106 water samples examined, 67 (63.2%) were positive for Legionella species. Amoebae were detected in 73 of 106 (68.9%) samples and in 56 of 67 (86.6%) Legionella species-positive samples (P < 10(-6)). In these positive samples, conductivity was lower than 500 microOmega(-1).cm(-1) in 58.2% (P = .026), temperature was below 50 degrees C in 80.6% (P = .004), and hardness was significantly higher (P = 002) than in Legionella species-negative samples. Neither Legionella species nor amoebae were isolated from any sampling point in which the water temperature was above 58.8 degrees C. Multivariate analysis shows that high hardness and presence of amoebae were strongly correlated statistically with the presence of Legionella when showers, tanks, pH, and temperature promoted their proliferation. This study shows the importance of water quality evaluation in assessing environmental risk factors and in selecting the most appropriate prevention and control measures in hospital water systems.

Impact of safety devices for preventing percutaneous injuries related to phlebotomy procedures in health care workers.

BACKGROUND: Use of protective devices has become a common intervention to decrease sharps injuries in the hospitals; however few studies have examined the results of implementation of the different protective devices available. OBJECTIVE: To determine the effectiveness of 2 protective devices in preventing needlestick injuries to health care workers. METHODS: Sharps injury data were collected over a 7-year period (1993-1999) in a 3600-bed tertiary care university hospital in France. Pre- and postinterventional rates were compared after the implementation of 2 safety devices for preventing percutaneous injuries (PIs) related to phlebotomy procedures. RESULTS: From 1993 to 1999, an overall decrease in the needlestick-related injuries was noted. Since 1996, the incidence of phlebotomy-related PIs has significantly decreased. Phlebotomy procedures accounted for 19.4% of all percutaneous injuries in the preintervention period and 12% in the postintervention period (RR, O.62; 95% CI, 0.51-0.72; P < .001). Needlestick-related injuries incidence rate decreased significantly after the implementation of the 2 safety devices, representing a 48% decline in incidence rate overall. CONCLUSIONS: The implementation of these safety devices apparently contributed to a significant decrease in the percutaneous injuries related to phlebotomy procedures, but they constitute only part of a strategy that includes education of health care workers and collection of appropriate data that allow analysis of residuals percutaneous injuries.