Microbial Burden Research Articles

Self-sanitizing copper-impregnated surfaces for bioburden reduction in patient rooms.

Novel self-sanitizing copper oxide-impregnated solid surfaces have the potential to influence bioburden levels, potentially lowering the risk of transmission of pathogens in patient care environments. Our study showed persistently lower microbial burden over a 30-hour sampling period on a copper-impregnated tray table compared with a standard noncopper surface in occupied patient rooms after thorough initial disinfection.

Microflora of Retained Intracochlear Electrodes from Infected Cochlear Implants.

Objectives Cochlear implant infections may be refractory to medical management and require device removal with subsequent reimplantation. During device removal, the intracochlear electrode array is commonly left in place to prevent obliteration of the cochlear lumen. If the electrode is colonized with pathogens, this risks contaminating the replacement implant. In this study, we compare the microorganisms detected on infected cochlear implants against those on the retained electrode using culture and microbial gene-sequencing techniques. Study Design Prospective single-cohort study. Setting Tertiary medical center. Subjects and Methods Six patients with refractory cochlear implant infections had the receiver-stimulator and extracochlear electrode removed to facilitate treatment of the infection. The intracochlear electrode was removed at (delayed) reimplantation. Implant specimens were analyzed by microbial culture and 16S DNA gene sequencing. Results Staphylococcus aureus was the organism most commonly identified. None of the 6 patients' intracochlear electrodes yielded microbes by culture. Two intracochlear electrodes revealed bacterial species, and 1 revealed fungal species by gene sequencing. There was no correlation between the microbes on the infected extracochlear implants and the retained intracochlear electrodes. All subjects underwent reimplantation after resolution of their infections. One of 6 subjects developed a second infection after reimplantation, with S aureus in the primary and secondary infections. Conclusions The intracochlear electrodes of infected cochlear implants carry a low microbial burden. Preserving intracochlear electrodes upon removal of infected cochlear implants appears to carry a low risk of contaminating a replacement cochlear implant.

Therapeutic Restoration of Endothelial Glycocalyx in Sepsis.

Endothelial glycocalyx (EG) is disintegrated during sepsis. We have previously shown that this occurs very early in the course of sepsis and its prevention improves the survival of mice with sepsis. Here, we sought to investigate the possibility of pharmacologically accelerating the restoration of disintegrated EG in sepsis. We used a soilage injection model to induce polymicrobial sepsis in C57/BL6 mice and measured total body EG. En face aortic preparations were used for staining of markers of EG and atomic force microscopy was used to measure EG in vitro. In vitro studies were conducted in cultured endothelial cells either exposed to a lipopolysaccharide or enzymatically denuded of EG. Sulodexide (SDX), a heparin sulfate-like compound resistant to degradation by heparanase, accelerated EG regeneration in vitro and in vivo. The total volume of EG was drastically reduced in septic mice. Administration of SDX produced a dramatic acceleration of EG restoration. This effect, unrelated to any SDX-induced differences in microbial burden, was associated with better control of vascular permeability. Notably, SDX demonstrated not only a remarkable capacity for EG regeneration in vitro and in vivo but was also associated with improved animal survival, even when instituted 2 hours after induction of severe sepsis. In conclusion, 1) EG is disintegrated in sepsis, the event which contributes to high animal mortality; 2) pharmacologic acceleration of EG restoration can be achieved using SDX; and 3) SDX reduces vascular permeability, which is elevated in septic mice, and improves animal survival.

Disturbances of the Perioperative Microbiome Across Multiple Body Sites in Patients Undergoing Pancreaticoduodenectomy.

The goals of this study were to characterize bacterial communities within fecal samples, pancreatic fluid, bile, and jejunal contents from patients undergoing pancreaticoduodenectomy (PD) and to identify associations between microbiome profiles and clinical variables. Fluid was collected from the pancreas, common bile duct, and proximal jejunum from 50 PD patients. Postoperative fecal samples were also collected. The microbial burden within samples was quantified with droplet digital polymerase chain reaction. Bacterial 16S ribosomal RNA gene sequences were amplified, sequenced, and analyzed. Data from fecal samples were compared with publicly available data obtained from volunteers. Droplet digital polymerase chain reaction confirmed the presence of bacteria in all sample types, including pancreatic fluid. Relative to samples from the American Gut Project, fecal samples from PD patients were enriched with Klebsiella and Bacteroides and were depleted of anaerobic taxa (eg, Roseburia and Faecalibacterium). Similar patterns were observed within PD pancreas, bile, and jejunal samples. Postoperative fecal samples from patients with a pancreatic fistula contained increased abundance of Klebsiella and decreased abundance of commensal anaerobes, for example, Ruminococcus. This study confirms the presence of altered bacterial populations within samples from PD patients. Future research must validate these findings and may evaluate targeted microbiome modifications to improve outcomes in PD patients.

Influence of Transportation Conditions and Postharvest Disinfection Treatments on Microbiological Quality of Fresh Market Tomatoes (cv. Nemo-Netta) in a South African Supply Chain

Postharvest microbial spoilage due to suboptimal transportation and packaging conditions is a key concern for the South African tomato industry. This study investigated the influence of washing with tap water or aqueous disinfectant solutions (chlorinated and anolyte water) on the microbiological quality of tomatoes during storage after transportation in nonrefrigerated trucks along two supply routes when packaged in crates and boxes. Route 1 was 1,093 km from field to storage site, while route 2 was 1,057 km. During transport, the temperature in the trucks fluctuated between 16 and 28°C and the relative humidity between 25 and 94% for route 1, while for route 2, the temperature was between 16 and 30°C and the relative humidity between 28 and 71%. Tomatoes at the pink maturity stage were sampled, treated, and stored for 28 days (11°C). The tomato firmness before treatment was 24.8 N (box samples) and 17.4 N (crate samples) for route 1, whereas it was 22.1 N (box samples) and 20.2 N (crate samples) for route 2. Temperature fluctuation during transportation led to water condensation on tomato surfaces. Tomatoes treated with anolyte water showed the lowest microbial surface burden during storage, with mean aerobic plate counts (APC) of 2.9 log CFU/cm2, coliform counts (CC) of 1.1 log CFU/cm2, and fungal counts (FC) of 2.3 log CFU/cm2. Overall, of the total APC recorded during storage, anolyte-treated samples contributed 9% while chlorinated water-treated samples contributed 30%. Of the total CC, anolyte samples presented 3% while chlorinated water samples made up 12%, and of the total recorded FC, anolyte samples contributed 7% while chlorinated water samples made up 22%. Scanning electron microscopy imaging showed surface cracks, which enable microbial colonization in crate-transported tomatoes. A combination of anolyte treatment and box packaging during transport resulted in the best microbiological quality during storage. The findings of this investigation provide motivation for the adoption of anolyte water as a postharvest disinfection treatment in the tomato industry.

Metabolic reprogramming and tolerance during sepsis-induced AKI

The host defence against infection is an adaptive response in which several mechanisms are deployed to decrease the pathogen load, limit tissue injury and restore homeostasis. In the past few years new evidence has suggested that the ability of the immune system to limit the microbial burden - termed resistance - might not be the only defence mechanism. In fact, the capacity of the host to decrease its own susceptibility to inflammation- induced tissue damage - termed tolerance - might be as important as resistance in determining the outcome of the infection. Metabolic adaptations are central to the function of the cellular immune response. Coordinated reprogramming of metabolic signalling enables cells to execute resistance and tolerance pathways, withstand injury, steer tissue repair and promote organ recovery. During sepsis-induced acute kidney injury, early reprogramming of metabolism can determine the extent of organ dysfunction, progression to fibrosis, and the development of chronic kidney disease. Here we discuss the mechanisms of tolerance that act in the kidney during sepsis, with particular attention to the role of metabolic responses in coordinating these adaptive strategies. We suggest a novel conceptual model of the cellular and organic response to sepsis that might lead to new avenues for targeted, organ-protective therapies.

Quantitative Analysis of Microbial Burden on Hospital Room Environmental Surfaces Contributing to Healthcare-Associated Infections

Background Contaminated environmental surfaces are involved in the transmission of epidemiologically important pathogens. It remains unknown which level of microbial load can contribute to healthcare-associated infections (HAI). We used microbiological data obtained from the Benefits of Enhanced Terminal Room (BETR) Disinfection Study to investigate the quantitative relationship between microbial burden and risk of HAI.Methods Microbiological samples were collected from high-frequency-touch hospital room surfaces using Rodac plates (25 cm2/plate) in rooms after terminal room disinfection. All rooms were randomly assigned to standard disinfection (Quaternary ammonium [Quat]) or an enhanced disinfection (Quat/ultraviolet light [UV-C], Bleach, Bleach/UV-C). The Quat/UV-C arm was excluded from further analysis since HAI were not observed in this arm. All new patients in study rooms were monitored for HAI following terminal disinfection through the BETR study standard protocols. We analyzed the relationship between the total colony forming units (CFU) of bacterial loads from 2,395 environmental samples in 60 rooms and HAI among new patients in the room (6 patients with HAI and 54 patients without HAI). Each arm had 2 patients with HAI. Statistical significance was determined by the Wilcoxon test, and P < 0.05 was considered significant.ResultsOverall, samples in rooms of patients with HAI had a mean 39.3 CFU, while samples from rooms of patients without HAI had a mean 35.6 CFU (Table 1). In the standard disinfection, the sampled rooms from the HAI patients had a significantly higher number of total CFU (mean 65.1 CFU) than non-HAI group (mean 35.5 CFU) (P = 0.019). In the enhanced disinfection rooms, there was no statistical significance between HAI and non-HAI groups.Conclusion Although our sample size may have been too small to detect contaminated microbial load in a room though a large clinical trial was conducted, our data based on the Quat arm as standard disinfection demonstrated the significant relationship between microbial load and HAI.Disclosures D. Sexton, Centers for Disease Control and Prevention: Grant Investigator, Grant recipient. Centers for Disease Control and Prevention Foundation: Grant Investigator, Grant recipient. UpToDate: Collaborator, Royalty Recipient. D. J. Weber, PDI: Consultant, Consulting fee

Probiotics and Chronic Liver Diseases

Probiotics and Chronic Liver Diseases

Does Cleaning Time Matter? A Study to Determine the Effect of Unlimited vs. Limited Time for Terminal Disinfection

Background Although the national target for the amount of time dedicated to cleaning a hospital room following patient discharge is 45 minutes, there is no conclusive evidence that cleaning duration is related to the quality of clean in terms of microbial load. Using data from a larger study on hospital room disinfection we examined the relationship between manual cleaning time and microbial burden as assessed by aerobic bacterial colony (ABC) count on high-touch surfaces.Methods Six hundred pre-clean and post-clean samples were taken from 5 different high-touch surfaces (bedrail, tray table, call button, toilet seat, and bathroom handrail) in 44 different patient rooms. Three cleaning time categories were studied: Time limited to 25 minutes; unlimited cleaning time where the housekeeper took <45 minutes; and unlimited cleaning time where the housekeeper took ≥45 minutes. The relationship between cleaning time category and post-manual clean ABC count was assessed using a conditional inference regression tree that was modeled for the outcome variable ABC count and the predictors cleaning time category and other potential confounders.ResultsThere was no difference in ABC count for hydrogen peroxide and sodium hypochlorite 10% between the different categories of cleaning time. For quaternary ammonium compound and soap and water, the limited cleaning time category showed lower ABC counts than the unlimited time categories for samples taken from isolation rooms, P = 0.009. For 150 soap and water samples, 61 showed an increase in ABC count from the pre-clean sample to post-clean sample.Conclusion Cleaning time was not related to post-clean ABC count for sodium hypochlorite 10% or Hydrogen Peroxide. Limited cleaning time was more effective in lowering ABC counts for quaternary ammonium compound and for soap and water. For soap and water, post-clean ABC counts were actually higher than pre-clean ABC counts for numerous samples. This may be due to the spreading organisms across the surface while cleaning, without adequate disinfection.Disclosures C. Jinadatha, Xenex Healthcare Services: CRADA, Research support

Longitudinal assessment of the bacterial burden of buruli ulcer wounds during treatment

Background: Bacterial contamination is common to all wounds. The bacterial burden of wounds has been found to have an inverse relationship with chronic wound healing. In seeking to develop a better understanding of the evolution of Buruli ulcer (BU) wounds, we performed a longitudinal study to quantify the bacterial burden of BU wounds during the course of streptomycin/rifampicin (SR) treatment. Methods: Twenty-one IS2404 polymerase chain reaction confirmed patients were longitudinally followed during the course of their treatment. Swab or tissue samples obtained from the lesions were quantitatively analyzed to determine the bacterial burden pre-, during, and post-SR treatment. Furthermore, the species of bacterial isolates obtained at these time points were also identified. Results: Based on the determination of the bacterial burden, 18/22 (81.8%) pretreatment, 15/25 (57.7%) during treatment, and 36/48 (75.0%) posttreatment samples were classified as superinfected, respectively. Thirty bacterial species including two species of anaerobic Clostridia (Clostridium perfringens and Clostridium sporogenes) were identified among 114 isolates. While Enterococcus faecalis, Pseudomonas aeruginosa, and Chryseomonas luteola dominated pretreatment, P. aeruginosa dominated during and posttreatment. Conclusions: Most BU patients presented with lesions with a high bacterial load which increased significantly posttreatment. Therefore, good wound care is necessary to control the microbial burden of BU wounds, especially posttreatment to minimize complications.

Intranasal Delivery of Peptide-Morpholinos to Knockdown Influenza Host Factors in Mice.

Influenza viruses replicate primarily in the lung tissue of different host species. For efficient replication the virus utilizes host factors that are expressed in target cells. Cell-penetrating peptide-conjugated Morpholino oligomers (PPMOs) designed to target viral proteins have shown promising results as potential antiviral drugs in tissue culture and animal models. However, since viruses tend to have high rates of mutations, targeting viral proteins may result in viral escape mutants. An alternative approach to inhibit virus replication with PPMOs is to target host factors that are required for virus replication. Delivery of PPMO through the intranasal route has been shown to be effective in knockdown of host factors or microbial genes leading to protection against respiratory pathogens and reduced microbial burden. In addition, protective host innate antiviral immune responses in the lung can be studied by knockdown of immune signaling factors using PPMOs. Here we describe a successful approach using PPMOs to knockdown either proviral or antiviral host factors leading to changes in influenza virus replication in the lungs of mice, providing a tool to investigate immune responses and host-virus interactions in vivo.

Electronic and Microbiological Detection, Investigation, and Surveillance for Potential Hospital- Acquired Device Associated Infections at ERCP.

Background Duodenoscopy, done 700,000 times annually, is potentially life saving in biliary and pancreatic disease. ERCP is prone to device associated infections due to a complex elevator mechanism and slim margin of safety in scope reprocessing with a high microbial burden. Nosocomial infections are difficult to detect without a marker organism or antibiotic phenotype. A cluster of ESBL infections was detected by electronic surveillance in 2014 in a large 865 bed facility.Methods Utilizing electronic surveillance, a line listing of ESBLs from the prior year was made, and antibiotic phenotypes examined. After chart review, one phenotype Pattern A clustered with ERCP. Scopes were quarantined and cultured; isolates were sent out for pulsed-field gel electropheresis, and gene sequencing;patients and providers were notified; patients were offered rectal screening; additional scopes and new AERs purchased; double scope AER reprocessing with peracetic acid was centralized for five hospitals in the healthcare system; centralized weekly scope microbial sampling and monitoring after reprocessing was implemented 10/2015 using CDC guidance of March 2015; and prospective electronic surveillance of ERCP procedures was begun.ResultsTwenty-two phenotypes of ESBLs were found. Scope, environmental, and AER cultures were negative. Pattern A organisms were clonal. 235 patients of 274 exposed underwent screening with no additional pattern A isolated. Prevalence of ESBL colonization in this exposed cohort in New England was 11%. Scope post-reprocessing sampling and cultures were positive in 2015 for low concern organisms 5% of cultures, and one positive culture for an organism of high concern. Currently culture positivity is 1.3%, with 0% organisms of high concern for 18 months. Contamination of the culture media did occur rarely initially, and was detected by controls. Prospective electronic surveillance has identified no additional clusters.Conclusion Electronic infection control surveillance will detect device associated infections, aid the investigation, and monitor procedures prospectively. The CDC guidance for weekly sampling and culturing after ERCP is easily implemented after an initial investment of training, additional scopes, and lab support; expected positivity will be < 2 %.Disclosures All authors: No reported disclosures.

Cytocompatibility testing of cyclodextrin-functionalized antimicrobial textiles-a comprehensive approach.

Functionalized textiles can be used in wound management to reduce the microbial burden in the wound area, to prevent wound infections, and to avoid cross-contamination between patients. In the present study, a comprehensive in vitro approach to enable the assessment of antibacterial activity of functionalized textiles and cytotoxicity of cyclodextrin (CD)-complexes with chlorhexidine diacetate (CHX), iodine (IOD), and polihexanide (PHMB) is suggested to evaluate their properties for supporting optimal conditions for wound healing. For all β-CD-antiseptic functionalized cotton samples a strong antibacterial effect on the Gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis as well as on the Gram-negative bacteria Klebsiella pneumoniae and Escherichia coli was proven. In addition, β-CD-CHX and β-CD-PHMB were effective against the yeast Candida albicans. The growth of Pseudomonas aeruginosa could be reduced significantly by β-CD-IOD and β-CD-PHMB. The established comprehensive testing system for determination of biocompatibility on human HaCaT keratinocytes is suitable for obtaining robust data on cell viability, cytotoxicity and mode of cell death of the β-CD-antiseptic-complexes. The promising results of the high antimicrobial activity of these functionalized textiles show the high potential of such materials in medical applications.

Predatory Bacteria Attenuate Klebsiella pneumoniae Burden in Rat Lungs.

ABSTRACTBdellovibrio bacteriovorus and Micavibrio aeruginosavorus are predatory bacteria that naturally—and obligately—prey on other Gram-negative bacteria, and their use has been proposed as a potential new approach to control microbial infection. The ability of predatory bacteria to prey on Gram-negative human pathogens in vitro is well documented; however, the in vivo safety and efficacy of predatory bacteria have yet to be fully assessed. In this study, we examined whether predatory bacteria can reduce bacterial burden in the lungs in an in vivo mammalian system. Initial safety studies were performed by intranasal inoculation of rats with predatory bacteria. No adverse effects or lung pathology were observed in rats exposed to high concentrations of predatory bacteria at up to 10 days postinoculation. Enzyme-linked immunosorbent assay (ELISA) of the immune response revealed a slight increase in inflammatory cytokine levels at 1 h postinoculation that was not sustained by 48 h. Additionally, dissemination experiments showed that predators were efficiently cleared from the host by 10 days postinoculation. To measure the ability of predatory bacteria to reduce microbial burden in vivo, we introduced sublethal concentrations of Klebsiella pneumoniae into the lungs of rats via intranasal inoculation and followed with multiple doses of predatory bacteria over 24 h. Predatory bacteria were able to reduce K. pneumoniae bacterial burden, on average, by more than 3.0 log10 in the lungs of most rats as measured by CFU plating. The work presented here provides further support for the idea of developing predatory bacteria as a novel biocontrol agent.

A Combination Regimen Design Program Based on Pharmacodynamic Target Setting for Childhood Tuberculosis: Design Rules for the Playground.

Children with tuberculosis are treated with drug regimens copied from adults despite significant differences in antibiotic pharmacokinetics, pathology, and the microbial burden between childhood and adult tuberculosis. We sought to develop a new and effective oral treatment regimen specific to children of different ages. We investigated and validated the concept that target drug concentrations associated with therapy failure and death in children are different from those of adults. On that basis, we proposed a 4-step program to rapidly develop treatment regimens for children. First, target drug concentrations for optimal efficacy are derived from preclinical models of disseminated tuberculosis that recapitulate pediatric pharmacokinetics, starting with monotherapy. Second, 2-drug combinations were examined for zones of synergy, antagonism, and additivity based on a whole exposure–response surface. Exposures associated with additivity or synergy were then combined and the regimen was compared to standard therapy. Third, several exposures of the third drug were added, and a 3-drug regimen was identified based on kill slopes in comparison to standard therapy. Fourth, computer-aided clinical trial simulations are used to identify clinical doses that achieve these kill rates in children in different age groups. The proposed program led to the development of a 3-drug combination regimen for children from scratch, independent of adult regimens, in <2 years. The regimens and doses can be tested in animal models and in clinical trials.

Intra-Operative Surgical Irrigation of the Surgical Incision: What Does the Future Hold-Saline, Antibiotic Agents, or Antiseptic Agents?

Intra-operative surgical site irrigation (lavage) is common practice in surgical procedures in general, with all disciplines advocating some form of irrigation before incision closure. This practice, however, has been neither standardized nor is there compelling evidence that it effectively reduces the risk of surgical site infection (SSI). This narrative review addresses the laboratory and clinical evidence that is available to support the practice of irrigation of the abdominal cavity and superficial/deep incisional tissues, using specific irrigation solutions at the end of an operative procedure to reduce the microbial burden at wound closure. Review of PubMed and OVID for pertinent, scientific, and clinical publications in the English language was performed. Incision irrigation was found to afford a three-fold benefit: First, to hydrate the bed; second, to assist in allowing better examination of the area immediately before closure; and finally, by removing superficial and deep incisional contamination and lowering the bioburden, expedite the healing process. The clinical practice of intra-operative peritoneal lavage is highly variable and is dependent solely on surgeon preference. By contrast, intra-operative irrigation after device-related procedures has become a standard of care for the prophylaxis of acute peri-prosthetic infection. The clinical evidence that supports the use of antibiotic irrigation is limited and based on retrospective analysis and few acceptable randomized controlled trials. The results of laboratory and animal studies using aqueous 0.05% chlorhexidine gluconate are favorable, suggesting that further studies are justified to determine its clinical efficacy. The adoption of appropriate and standardized intra-operative irrigation practices into peri-operative care bundles, which include other evidence-based strategies (weight-based antimicrobial prophylaxis, antimicrobial sutures, maintenance of normothermia, and glycemic control), offers an inexpensive and effective method to reduce the risk of post-operative SSI and deserves further evaluation.

Multiple factors influencing OR ventilation system effectiveness

Abstract The issue of surgical site infections has become more critical during the last years. The number of airborne microbes depends on the number released by the staff in the room or supplied from neighbouring rooms. In order to minimize the risk of nosocomial infections during surgical procedures technical developments like ventilation systems were introduced in the operating room (OR). In this study several factors like clothing and types of ventilation systems have been investigated and their impact on the effectiveness for reducing microbial burden in the OR has been assessed. In case of OR-gowns we found a benefit for a disposable Swedish clothing concept regarding microbiological contamination in comparison with the German standard multiuse clothing. Moreover our study shows that there is comparable effectiveness of a fairly novel temperature controlled airflow ventilation system (TAF) compared to standard low turbulent uni-directional airflow (TAV).

Temporal Stability in Chronic Wound Microbiota Is Associated With Poor Healing

Microbial burden of chronic wounds is believed to play an important role in impaired healing and the development of infection-related complications. However, clinical cultures have little predictive value of wound outcomes, and culture-independent studies have been limited by cross-sectional design and small cohort size. We systematically evaluated the temporal dynamics of the microbiota colonizing diabetic foot ulcers, a common and costly complication of diabetes, and its association with healing and clinical complications. Dirichlet multinomial mixture modeling, Markov chain analysis, and mixed-effect models were used to investigate shifts in the microbiota over time and their associations with healing. Here we show, to our knowledge, previously unreported temporal dynamics of the chronic wound microbiome. Microbiota community instability was associated with faster healing and improved outcomes. Diabetic foot ulcer microbiota were found to exist in one of four community types that experienced frequent and nonrandom transitions. Transition patterns and frequencies were associated with healing time. Exposure to systemic antibiotics destabilized the wound microbiota, rather than altering overall diversity or relative abundance of specific taxa. This study provides evidence that the dynamic wound microbiome is indicative of clinical outcomes and may be a valuable guide for personalized management and treatment of chronic wounds.

Cutaneous microbiome effects of fluticasone propionate cream and adjunctive bleach baths in childhood atopic dermatitis

Patients with atopic dermatitis (AD) are prone to skin infections, with microbes such as Staphylococcus aureus suspected of contributing to pathogenesis. Bleach baths might improve AD by reducing skin microbial burden. We sought to characterize the microbiota of lesional and nonlesional skin in young children with AD and control subjects and compare changes after treatment with a topical corticosteroid (TCS) alone or TCS+dilute bleach bath. In a randomized, placebo-controlled, single-blinded clinical trial in 21 children with AD and 14 healthy children, lesional and nonlesional AD skin was examined at baseline and after 4-week treatment with TCS alone or TCS plus bleach bath. Microbial DNA was extracted for quantitative polymerase chain reaction of predominant genera and 16S rRNAsequencing. At baseline, densities of total bacteria and Staphylococcus, including Staphylococcus aureus, were significantly higher at the worst AD lesional site than nonlesional (P=.001) or control (P<.001) skin; bacterial communities on lesional and nonlesional AD skin significantly differed from each other (P=.04) and from control (P<.001). After TCS+bleach bath or TCS alone, bacterial compositions on lesional skin normalized (P<.0001), resembling nonlesional skin, with microbial diversity restored to control skin levels. The 4-week time period and/or the twice-weekly baths may not have been sufficient for additional impact on the cutaneous microbiome. More detailed sequencing may allow better characterization of the distinguishing taxa with bleach bath treatment. Treatment with a TCS cream suffices to normalize the cutaneous microbiota on lesional AD; after treatment, bacterial communities on lesional skin resemble nonlesional skin but remain distinct from control.

Chlorhexidine Bathing Effects on Health-Care-Associated Infections.

Health-care-associated infections (HAIs), infections that patients contract during the course of their hospitalization, are receiving a growing amount of attention. Heavy skin bacterial colonization aids in the transmission and development of HAIs. Nurses frequently use bathing with chlorhexidine gluconate (CHG) to reduce patients' cutaneous microbial burden. This intervention has been shown to have promising but mixed results in the prevention of HAIs. This article reviews the literature for evidence on the impact of CHG bathing on HAIs. A literature search was conducted to identify peer-reviewed studies and meta-analyses that examined the impact of CHG bathing on HAIs using PubMed and CINAHL with the following search terms: CHG bathing AND healthcare associated infections, surgical site infections ( SSIs), central line associated bloodstream infections ( CLABSIs), ventilator-associated pneumonias ( VAP), catheter-associated urinary-tract infections ( CAUTIs), and Clostridium difficile-associated disease. The initial search identified 23 articles for review. Additional studies were identified by searching references used in original studies or review articles on this topic. There is good evidence to support incorporating a CHG bathing regimen to reduce the incidence of CLABSIs, SSIs, vancomycin-resistant enterococci (VRE), and methicillin-resistant Staphylococcus aureus (MRSA) HAIs. As CHG becomes a standard practice to prevent HAIs, it is important to monitor for adverse reactions and evidence of resistance/susceptibility.