A pilot study to assess use of fluorescent lotion in patient care simulations to illustrate pathogen dissemination and train personnel in correct use of personal protective equipment

BACKGROUND

Simulations using fluorescent tracers can be useful in understanding the spread of pathogens and in devising effective infection control strategies.

METHODS

During simulated patient care interactions in which providers wore gloves and gowns, we evaluated environmental and personnel dissemination of fluorescent lotion and bacteriophage MS2 from a contaminated mannequin. The frequency of skin and clothing contamination after removal of personal protective equipment (PPE) was compared before versus after an intervention that included education and practice in PPE donning and doffing.

RESULTS

Ten healthcare personnel participated in 30 pre-intervention and 30 post-intervention patient care simulations. Fluorescent lotion and bacteriophage MS2 were rapidly disseminated to touched surfaces throughout the room; there was no difference in the frequency of contamination before versus after the PPE training intervention. After the intervention, there was a decrease in skin and/or clothing contamination with fluorescent lotion (9/30, 30 % versus 1/30, 3 %; P = 0.01) and bacteriophage MS2 (8/30, 27 % versus 2/30, 7 %; P = 0.08) and there was a significant reduction in the concentration of bacteriophage MS2 recovered from hands (0.31 versus 0.07 log₁₀plaque-forming units; P < 0.01).

CONCLUSIONS

Our findings suggest that simulations with fluorescent lotion can be a useful teaching tool to illustrate the spread of pathogens and provide further evidence that simple PPE training interventions can be effective in reducing contamination of personnel.

A Quaternary Ammonium Disinfectant Containing Germinants Reduces Clostridium difficile Spores on Surfaces by Inducing Susceptibility to Environmental Stressors

Exposing Clostridium difficile spores to germinants in a quaternary ammonium matrix was an effective method to reduce environmental contamination by sensitizing the spores, leaving them susceptible to ambient conditions and enhancing killing by acid, high-intensity visible light, and radiation.

Fluoroquinolone-Resistant Escherichia coli Infections After Transrectal Biopsy of the Prostate in the Veterans Affairs Healthcare System

Background:

Recent reports suggest that infections due to fluoroquinolone-resistant Escherichia coli (E. coli) are an increasingly common complication of transrectal biopsy of the prostate (TBP) in the United States. A better understanding of the magnitude and scope of these infections is needed to guide prevention efforts. Our objective is to determine whether the incidence of infections due to fluoroquinolone-resistant E. coli after TBP has increased nationwide in the Veterans Affairs Health Care System and to identify risk factors for infection.

Methods:

We performed a retrospective, observational cohort study and a nested case-control study within the US Deparment of Veterans Affairs Healthcare System. The primary outcomes were the incidence of urinary tract infection (UTI) and bacteremia with E. coli and with fluoroquinolone-resistant E. coli strains within 30 days after TBP. Secondary endpoints focused on the correlation between fluoroquinolone-resistance in all urinary E. coli isolates and post-TBP infection and risk factors for infection due to fluoroquinolone-resistant E. coli infection.

Results:

245,618 patients undergoing 302,168 TBP procedures from 2000 through 2013 were included in the cohort study, and 59,469 patients undergoing TBP from 2011 through 2013 were included in the nested case-control study. Between 2000 and 2013, there was a 5-fold increase in the incidence of E. coli UTI (0.18%–0.93%) and a 4-fold increase in the incidence of E. coli bacteremia (0.04%–0.18%) after TBP that was attributable to an increase in the incidence of fluoroquinolone-resistant E. coli UTI (0.03%–0.75%) and bacteremia (0.01%–0.14%). The increasing incidence of fluoroquinolone-resistant E. coli infections after TBP occurred in parallel with increasing rates of fluoroquinolone-resistance in all urinary E. coli isolates. By multivariable logistic regression analysis, independent risk factors for fluoroquinolone-resistant E. coli UTI after TBP included diabetes mellitus, fluoroquinolone exposure, prior hospitalization, and prior cultures with fluoroquinolone-resistant gram-negative bacilli.

Conclusion:

In the Veterans Affairs Healthcare System, the incidence of E. coli infection after TBP has increased significantly since 2000 due to a dramatic rise in infections with fluoroquino-lone-resistant E. coli.

Fluoroquinolone-Resistant Escherichia coli Infections after Transrectal Biopsy of the Prostate in the Veterans Affairs Healthcare System

Background: Recent reports suggest that infections due to fluoroquinolone-resistant Escherichia coli (E. coli) are an increasingly common complication of transrectal biopsy of the prostate (TBP) in the United States. A better understanding of the magnitude and scope of these infections is needed to guide prevention efforts. Our objective is to determine whether the incidence of infections due to fluoroquinolone-resistant E. coli after TBP has increased nationwide in the Veterans Affairs Health Care System and to identify risk factors for infection.Methods: We performed a retrospective, observational cohort study and a nested case-control study within the US Deparment of Veterans Affairs Healthcare System. The primary outcomes were the incidence of urinary tract infection (UTI) and bacteremia with E. coli and with fluoroquinolone-resistant E. coli strains within 30 days after TBP. Secondary endpoints focused on the correlation between fluoroquinolone-resistance in all urinary E. coli isolates and post-TBP infection and risk factors for infection due to fluoroquinolone-resistant E. coli infection.Results: 245 618 patients undergoing 302 168 TBP procedures from 2000 through 2013 were included in the cohort study, and 59 469 patients undergoing TBP from 2011 through 2013 were included in the nested case-control study. Between 2000 and 2013, there was a 5-fold increase in the incidence of E. coli UTI (0.18%–0.93%) and a 4-fold increase in the incidence of E. coli bacteremia (0.04%–0.18%) after TBP that was attributable to an increase in the incidence of fluoroquinolone-resistant E. coli UTI (0.03%–0.75%) and bacteremia (0.01%–0.14%). The increasing incidence of fluoroquinolone-resistant E. coli infections after TBP occurred in parallel with increasing rates of fluoroquinolone-resistance in all urinary E. coli isolates. By multivariable logistic regression analysis, independent risk factors for fluoroquinolone-resistant E. coli UTI after TBP included diabetes mellitus, fluoroquinolone exposure, prior hospitalization, and prior cultures with fluoroquinolone-resistant gram-negative bacilli.Conclusion: In the Veterans Affairs Healthcare System, the incidence of E. coli infection after TBP has increased significantly since 2000 due to a dramatic rise in infections with fluoroquinolone-resistant E. coli.Keywords: bacteremia; case-control studies; cohort studies; early detection of cancer; Escherichia coliinfections; microbial drug resistance; postoperative complications; prostate; retrospective studies; United States Department of Veterans Affairs; urinary tract infections.

Are health care personnel trained in correct use of personal protective equipment?

Effective use of personal protective equipment (PPE) is essential to protect personnel and patients in health care settings. However, in a survey of 222 health care personnel, PPE training was often suboptimal with no requirement for demonstration of proficiency. Fourteen percent of physicians reported no previous training in use of PPE.

Effect of Surotomycin, a Novel Cyclic Lipopeptide Antibiotic, on Intestinal Colonization with Vancomycin-Resistant Enterococci and Klebsiella pneumoniae in Mice

Surotomycin (formerly called CB-183,315) is a novel, orally administered cyclic lipopeptide antibacterial in development for the treatment of Clostridium difficile infection (CDI) that has potent activity against vancomycin-resistant enterococci (VRE) but limited activity against Gram-negative bacilli, including Bacteroides spp. We used a mouse model to investigate the impact of surotomycin exposure on the microbiome, and to test the consequences of the disruption on colonization by vancomycin-resistant enterococci (VRE) and extended-spectrum β-lactamase-producing Klebsiella pneumoniae (ESBL-KP), in comparison with the effects of oral vancomycin and metronidazole. Mice (8 per group) received saline, vancomycin, metronidazole, or surotomycin through an orogastric tube daily for 5 days and were challenged with 10(5) CFU of VRE or ESBL-KP administered through an orogastric tube on day 2 of treatment. The concentrations of the pathogens in stool were determined during and after treatment by plating on selective media. A second experiment was conducted to determine if the antibiotics would inhibit established VRE colonization. In comparison to controls, oral vancomycin promoted VRE and ESBL-KP overgrowth in stool (8 log10 to 10 log10 CFU/g; P < 0.001), whereas metronidazole did not (<4 log10 CFU/g; P > 0.5). Surotomycin promoted ESBL-KP overgrowth (>8 log10 CFU/g; P, <0.001 for comparison with saline controls) but not VRE overgrowth. Surotomycin suppressed preexisting VRE colonization, whereas metronidazole and vancomycin did not. These results suggest that treatment of CDI with surotomycin could reduce levels of VRE acquisition and overgrowth from those with agents such as vancomycin and metronidazole. However, surotomycin and vancomycin may promote colonization by antibiotic-resistant Gram-negative bacilli.

Evaluation of an enclosed ultraviolet-C radiation device for decontamination of mobile handheld devices

Mobile handheld devices used in health care settings may become contaminated with health care-associated pathogens. We demonstrated that an enclosed ultraviolet-C radiation device was effective in rapidly reducing methicillin-resistant Staphylococcus aureus, and with longer exposure times, Clostridium difficile spores, on glass slides and reducing contamination on in-use mobile handheld devices.

Do piperacillin/tazobactam and other antibiotics with inhibitory activity against Clostridium difficile reduce the risk for acquisition of C. difficile colonization?

Background

Systemic antibiotics vary widely in in vitro activity against Clostridium difficile. Some agents with activity against C. difficile (e.g., piperacillin/tazobactam) inhibit establishment of colonization in mice. We tested the hypothesis that piperacillin/tazobactam and other agents with activity against C. difficile achieve sufficient concentrations in the intestinal tract to inhibit colonization in patients.

Methods

Point-prevalence culture surveys were conducted to compare the frequency of asymptomatic rectal carriage of toxigenic C. difficile among patients receiving piperacillin/tazobactam or other inhibitory antibiotics (e.g. ampicillin, linezolid, carbapenems) versus antibiotics lacking activity against C. difficile (e.g., cephalosporins, ciprofloxacin). For a subset of patients, in vitro inhibition of C. difficile (defined as a reduction in concentration after inoculation of vegetative C. difficile into fresh stool suspensions) was compared among antibiotic treatment groups.

Results

Of 250 patients, 32 (13 %) were asymptomatic carriers of C. difficile. In comparison to patients receiving non-inhibitory antibiotics or prior antibiotics within 90 days, patients currently receiving piperacillin/tazobactam were less likely to be asymptomatic carriers (1/36, 3 versus 7/36, 19 and 15/69, 22 %, respectively; P = 0.024) and more likely to have fecal suspensions with in vitro inhibitory activity against C. difficile (20/28, 71 versus 3/11, 27 and 4/26, 15 %; P = 0.03). Patients receiving other inhibitory antibiotics were not less likely to be asymptomatic carriers than those receiving non-inhibitory antibiotics.

Conclusions

Our findings suggest that piperacillin/tazobactam achieves sufficient concentrations in the intestinal tract to inhibit C. difficile colonization during therapy.

ID: 103: COMPARATIVE ANTIMICROBIAL EFFICACY OF TWO HAND-HYGIENE PRODUCTS IN INTENSIVE CARE UNITS: A RANDOMIZED CONTROLLED TRIAL

Background

Contaminated hands of healthcare workers (HCW) are an important source of transmission of healthcare-associated infections in the intensive care unit (ICU). Alcohol-based hand sanitizers, the primary form of hand hygiene in healthcare settings, are effective but do not provide sustained antimicrobial activity. The aim of this study was to quantitatively visualize the immediate and persistent antimicrobial effectiveness of 1% chlorhexidine gluconate (CHG)+61% ethanol versus 70% ethanol at 2-time points: immediately after application on normal skin flora and after hand contamination with environmental microbes in the ICU.

Methods

A prospective, randomized, double-blind clinical trial with crossover design and paired data was done in three medical ICUs in a large academic teaching hospital. Eligible personnel included permanent and temporary HCWs involved with direct patient care in the ICU. HCWs were randomly assigned to one of two hand hygiene products using a crossover design. Hand prints were obtained immediately after hand hygiene was performed and again after spending >5 minutes in the ICU common areas. The numbers of aerobic colony-forming units (CFU) were compared for the two groups after log transformation.

Results

A total of 51 HCWs completed testing of both products. On bare hands, use of CHG+alcohol was associated with significantly lower recovery of aerobic CFU, both immediately after use (0.27±0.38 and 0.88±0.55 log10 CFU; P=.035) and after spending time in the ICU common areas (1.81±0.48 and 2.17±0.35 log10 CFU; P<.0001). Both of the antiseptics were well tolerated by HCWs with no adverse events.

Conclusions

The CHG+alcohol product was associated with significantly lower aerobic bacterial colony counts on hands of healthcare personnel, both immediately after use and after spending time in ICU common areas. Further studies are needed to determine if the use of the CHG+alcohol product results in sustained antimicrobial protection against healthcare-associated pathogens on hands of HCW.

ID: 98: EFFECTIVENESS OF DAILY CHLORHEXIDINE BATHING FOR REDUCING GRAM NEGATIVE INFECTIONS: A META-ANALYSIS

Background

Multiple studies have demonstrated that daily chlorhexidine gluconate (CHG) bathing is associated with a significant reduction in infections caused by Gram positive pathogens. However, there is limited data on the effectiveness of daily CHG bathing on gram negative infections. The aim of this study was to determine if daily CHG bathing is effective in controlling and preventing gram negative infections in adult ICU patients.

Methods

We searched MEDLINE and 3 other databases for original studies comparing daily CHG bathing to soap and water bathing. All studies investigating the effectiveness of daily CHG bathing on gram negative infections were eligible. Two investigators extracted data independently on baseline characteristics, study design, form and concentration of CHG, incidence and outcomes related to gram negative infections. Data were combined by means of a random-effects model and pooled relative risk ratios (RRs) and 95% confidence intervals (CIs) were derived for overall gram negative infections and individual gram negative pathogens.

Results

Eleven studies (n=27,793 patients) met the inclusion criteria. Of these, 13,852 patients received daily CHG bathing, and 13,941 patients daily bathing with soap and water. Daily CHG bathing was not associated with a lower risk of gram negative infections (2.03% vs. 2.38%; RR 0.84; 95%CI: 0.64–1.09, P=.19). Subgroup analysis demonstrated that daily CHG bathing significantly reduced the risk of gram negative infections caused by Acinetobacter (RR, 0.33; 95% CI: 0.17–0.66, P<.00001) but was not effective for E. coli, Klebsiella, Enterobacter and Pseudomonas associated gram negative infections.

Conclusions

In a meta-analysis of 11 studies, the use of daily CHG was not associated with a lower risk of gram negative infections. However, daily CHG bathing appears to be effective for Acinetobacter associated gram negative infections. There is a need for larger and better designed trials with adequate power with gram negative infections as the primary endpoint to determine the effectiveness of daily CHG bathing.

Abstract ID: 98 Figure 1

A Cumulative Spore Killing Approach: Synergistic Sporicidal Activity of Dilute Peracetic Acid and Ethanol at Low pH Against Clostridium difficile and Bacillus subtilis Spores

The synergistic combination of dilute peracetic acid and ethanol at low pH provides a novel approach for development of a rapid and effective method for reducing C. difficile spores on skin.

Background. Alcohol-based hand sanitizers are the primary method of hand hygiene in healthcare settings, but they lack activity against bacterial spores produced by pathogens such as Clostridium difficile and Bacillus anthracis. We previously demonstrated that acidification of ethanol induced rapid sporicidal activity, resulting in ethanol formulations with pH 1.5–2 that were as effective as soap and water washing in reducing levels of C difficile spores on hands. We hypothesized that the addition of dilute peracetic acid (PAA) to acidified ethanol would enhance sporicidal activity while allowing elevation of the pH to a level likely to be well tolerated on skin (ie, >3).

Methods. We tested the efficacy of acidified ethanol solutions alone or in combination with PAA against C difficile and Bacillus subtilis spores in vitro and against nontoxigenic C difficile spores on hands of volunteers.

Results. Acidification of ethanol induced rapid sporicidal activity against C difficile and to a lesser extent B subtilis. The addition of dilute PAA to acidified ethanol resulted in synergistic enhancement of sporicidal activity in a dose-dependent fashion in vitro. On hands, the addition of 1200–2000 ppm PAA enhanced the effectiveness of acidified ethanol formulations, resulting in formulations with pH >3 that were as effective as soap and water washing.

Conclusions. Acidification and the addition of dilute PAA induced rapid sporicidal activity in ethanol. Our findings suggest that it may be feasible to develop effective sporicidal ethanol formulations that are safe and tolerable on skin.