International Nosocomial Infection Control Consortium (INICC) report, data summary of 36 countries, for 2004-2009

Multicenter study in Colombia: Impact of a multidimensional International Nosocomial Infection Control Consortium (INICC) approach on central line-associated bloodstream infection rates

BACKGROUND

The objective of this study was to analyze the impact of a multidimensional infection control approach and the use of the International Nosocomial Infection Control Consortium (INICC) Surveillance Online System on central line-associated bloodstream infection (CLABSI) rates from June 2003-April 2010.

METHODS

We conducted a prospective, before-after surveillance study of 2,564 patients hospitalized in 4 adult intensive care units (ICUs) and 424 patients in 2 pediatric ICUs of 4 hospitals in 2 cities of Colombia. During baseline, we performed outcome surveillance of CLABSI applying the Centers for Disease Control and Prevention's National Healthcare Safety Network definitions. During intervention, we implemented the INICC multidimensional approach and the ISOS, which included a bundle of infection prevention practice interventions, education, outcome surveillance, process surveillance, feedback on CLABSI rates and consequences, and performance feedback of process surveillance. Bivariate and multivariate regression analyses were performed using a logistic regression model to estimate the effect of the intervention on the CLABSI rate.

RESULTS

The baseline rate of 12.9 CLABSIs per 1,000 central line (CL) days, with 3,032 CL days and 39 CLABSIs, was reduced to 3.5 CLABSIs per 1,000 CL days, with 3,686 CL days and 13 CLABSIs, accounting for a 73% CLABSI rate reduction (relative risk, 0.27; 95% confidence interval, 0.14-0.52; P=.002).

CONCLUSIONS

Implementing the INICC multidimensional infection control approach for CLABSI prevention was associated with a significant reduction in the CLABSI rate of ICUs of Colombia.

Lung ultrasound: a promising tool to monitor ventilator-associated pneumonia in critically ill patients

Ventilator-associated pneumonia (VAP) is the most frequent intensive care unit (ICU)-acquired infection that is independently associated with mortality. Accurate diagnosis and timely treatment have been shown to improve the prognosis of VAP. Chest X-ray or computed tomography imaging are used for conventional assessment of VAP, but these methods are impractical for real-time measurement in critical patients. Therefore, lung ultrasound (LUS) has been increasingly used for the assessment of VAP in the ICU. Traditionally, LUS has seemed unsuitable for the detection of lung parenchyma owing to the high acoustic impedance of air; however, the fact that the reflection and reverberation in the detection region of the ultrasound reflect the underlying pathology of lung diseases has led to the increased use of ultrasound imaging as a standard of care supported by evidence-based and expert consensus in the ICU. Considering that any type of pneumonia causes air volume changes in the lungs, accumulating evidence has shown that LUS effectively measures the presence of VAP as well as dynamic changes in VAP. This review offers evidence for ultrasound as a noninvasive, easily repeatable, and bedside means to assess VAP; in addition, it establishes a protocol for qualitative and quantitative monitoring of VAP.

Staphylococcus epidermidis ΔSortase A strain elicits protective immunity against Staphylococcus aureus infection

Staphylococcus aureus and Staphylococcus epidermidis are two of the most significant opportunistic human pathogens, causing medical implant and nosocomial infections worldwide. These bacteria contain surface proteins that play crucial roles in multiple biological processes. It has become apparent that they have evolved a number of unique mechanisms by which they can immobilise proteins on their surface. Notably, a conserved cell membrane-anchored enzyme, sortase A (SrtA), can catalyse the covalent attachment of precursor bacterial cell wall-attached proteins to peptidoglycan. Considering its indispensable role in anchoring substrates to the cell wall and its effects on virulence, SrtA has attracted great attention. In this study, a 549-bp gene was cloned from a pathogenic S. epidermidis strain, YC-1, which shared high identity with srtA from other Staphylococcus spp. A mutant strain, YC-1ΔsrtA, was then constructed by allelic exchange mutagenesis. The direct survival rate assay suggested that YC-1ΔsrtA had a lower survival capacity in healthy mice blood compare with the wild-type strain, indicating that the deletion of srtA affects the virulence and infectious capacity of S. epidermidis YC-1. YC-1ΔsrtA was then administered via intraperitoneal injection and it provided a relative percent survival value of 72.7 % in mice against S. aureus TC-1 challenge. These findings demonstrate the possbility that YC-1ΔsrtA might be used as a live attenuated vaccine to produce cross-protection against S. aureus.

Staff education aimed at reducing ventilator-associated pneumonia

Mechanical ventilation is a life-saving invasive procedure performed in intensive care units (ICUs) where critical patients are given advanced support. The purpose of this study was to assess the effect of personnel training on the incidence of ventilator-associated pneumonia (VAP). The study, performed prospectively in the ICU, was planned in two periods. In both periods, patient characteristics were recorded on patient data forms. In the second period, ICU physicians and assistant health personnel were given regular theoretical and practical training. Twenty-two cases of VAP developed in the pre-training period, an incidence of 31.2. Nineteen cases of VAP developed in the post-training period, an incidence of 21.0 (P<0.001). Training reduced development of VAP by 31.7 %. Crude VAP mortality was 69 % in the first period and 26 % in the second (P<0.001). Statistically significant risk factors for VAP in both periods were prolonged hospitalization, increased number of days on mechanical ventilation, and enteral nutrition; risk factors determined in the first period were re-intubation, central venous catheter use and heart failure and, in the second period, erythrocyte transfusion >5 units (P<0.05). Prior to training, compliance with hand washing (before and after procedure), appropriate aseptic endotracheal aspiration and adequate oral hygiene in particular were very low. An improvement was observed after training (P<0.001). The training of personnel who will apply infection control procedures for the prevention of healthcare-associated infections is highly important. Hand hygiene and other infection control measures must be emphasized in training programmes, and standard procedures in patient interventions must be revised.

Fitness Cost of Fluoroquinolone Resistance in Clinical Isolates of Pseudomonas aeruginosa Differs by Type III Secretion Genotype

Fluoroquinolone (FQ) resistance is highly prevalent among clinical strains of Pseudomonas aeruginosa, limiting treatment options. We have reported previously that highly virulent strains containing the exoU gene of the type III secretion system are more likely to be FQ-resistant than strains containing the exoS gene, as well as more likely to acquire resistance-conferring mutations in gyrA/B and parC/E. We hypothesize that FQ-resistance imposes a lower fitness cost on exoU compared to exoS strains, thus allowing for better adaptation to the FQ-rich clinical environment. We created isogenic mutants containing a common FQ-resistance conferring point mutation in parC from three exoU to three exoS clinical isolates and tested fitness in vitro using head-to-head competition assays. The mutation differentially affected fitness in the exoU and exoS strains tested. While the addition of the parC mutation dramatically increased fitness in one of the exoU strains leaving the other two unaffected, all three exoS strains displayed a general decrease in fitness. In addition, we found that exoU strains may be able to compensate for the fitness costs associated with the mutation through better regulation of supercoiling compared to the exoS strains. These results may provide a biological explanation for the observed predominance of the virulent exoU genotype in FQ-resistant clinical subpopulations and represent the first investigation into potential differences in fitness costs of FQ-resistance that are linked to the virulence genotype of P. aeruginosa. Understanding the fitness costs of antibiotic resistance and possibilities of compensation for these costs is essential for the rational development of strategies to combat the problem of antibiotic resistance.

Prospective observational study to compare oral topical metronidazole versus 0.2% chlorhexidine gluconate to prevent nosocomial pneumonia

BACKGROUND

Nosocomial pneumonia is one of the most common health care-associated infections in intensive care units (ICUs) worldwide, attributing to high morbidity and mortality. Our study aim is to investigate the effectiveness of oral hygiene with 0.2% chlorhexidine gluconate (CHX) and 0.08% metronidazole (MDE) influencing the microbiologic epidemiology and incidence of nonintubation pneumonia (NIP) and ventilator-associated pneumonia (VAP).

METHODS

Patients who stayed >48 hours in the emergency ICU between 2008 and 2012 were enrolled and provided oral hygiene by swabbing with 0.08% MDE twice daily until discharge or death during the first year (period M), whereas CHX was applied during the following 3 years (period C). The incidence and microbiologic epidemiology of NIP and VAP were studied.

RESULTS

There were 873 patients enrolled. There were 44 episodes of NIP and 25 episodes of VAP that occurred among 212 patients in period M, and 84 episodes of NIP and 49 episodes of VAP occurred among 661 patients in period C. Overall, the rate of NIP and VAP decreased year by year. Acinetobacter baumannii was the most frequently identified bacteria for NIP (22.9%) and VAP (25.3%), with an annual ascent. Few changes were observed on bacteria distribution for NIP and VAP.

CONCLUSIONS

Oral hygiene with CHX, having reduced the incidence of nosocomial pneumonia among critical ill patients, suggests a benefit of oral hygiene in decreasing the incidence of nosocomial pneumonia, including VAP in ICUs, but not bacterial epidemiology.

Prevention of nosocomial infections in critically ill patients with lactoferrin (PREVAIL study): study protocol for a randomized controlled trial

BACKGROUND

Nosocomial infections remain an important source of morbidity, mortality, and increased health care costs in hospitalized patients. This is particularly problematic in intensive care units (ICUs) because of increased patient vulnerability due to the underlying severity of illness and increased susceptibility from utilization of invasive therapeutic and monitoring devices. Lactoferrin (LF) and the products of its breakdown have multiple biological effects, which make its utilization of interest for the prevention of nosocomial infections in the critically ill.

METHODS/DESIGN

This is a phase II randomized, multicenter, double-blinded trial to determine the effect of LF on antibiotic-free days in mechanically ventilated, critically ill, adult patients in the ICU. Eligible, consenting patients will be randomized to receive either LF or placebo. The treating clinician will remain blinded to allocation during the study; blinding will be maintained by using opaque syringes and containers. The primary outcome will be antibiotic-free days, defined as the number of days alive and free of antibiotics 28 days after randomization. Secondary outcomes will include: antibiotic utilization, adjudicated diagnosis of nosocomial infection (longer than 72 h of admission to ICU), hospital and ICU length of stay, change in organ function after randomization, hospital and 90-day mortality, incidence of tracheal colonization, changes in gastrointestinal permeability, and immune function. Outcomes to inform the conduct of a larger definitive trial will also be evaluated, including feasibility as determined by recruitment rates and protocol adherence.

DISCUSSION

The results from this study are expected to provide insight into a potential novel therapeutic use for LF in critically ill adult patients. Further, analysis of study outcomes will inform a future, large-scale phase III randomized controlled trial powered on clinically important outcomes related to the use of LF.

TRIAL REGISTRATION

The trial was registered at www.ClinicalTrials.gov on 18 November 2013.

TRIAL REGISTRATION NUMBER

NCT01996579 .

Frequency of hospital acquired pneumonia and its microbiological etiology in medical intensive care unit

OBJECTIVE

The objectives were to assess the frequency of hospital acquired pneumonia (HAP) in patients admitted to intensive care unit (ICU) and to determine the frequencies of different etiological organisms in these patients.

METHODS

This was descriptive cross sectional study, which was carried out in medical ICU of Shifa International Hospital Islamabad from January 2013 to January 2014. A total of 1866 patients were admitted in the department of medicine including medical ICU. They were evaluated for HAP and the causative organisms were cultured from these patients. Identification was carried out by standard biochemical profile of the organisms.

RESULTS

The total number of patients admitted in medical ICU for any reason were 346. HAP was diagnosed in 88 patients (25.4%). The average age of patients admitted in Medical ICU with HAP was 48 years with the range of 16 to 82 years. 56 were male and 32 females. 42 patients (47.7%) died in medical ICU with HAP. Microbiological analysis showed that Pseudomonas aeruginosa were 27 (30.6%), Acinetobacter spp. were 12 (13.6%), Candida albicans were 12 (13.6%), Klebsiellapneumoniae were 9 (10.2%), Streptococcus spp. were 9 (10.2%), Escherichia coli were 5 (5.6%), Stenotrophomonas spp. were 4(4.5%), Methicillin Resistant Staphylococcus Aureus (MRSA) were 4 (4.5%) others organisms 6 (6.8%).

CONCLUSION

The frequency of HAP in Medical ICU of our hospital is 88 out of 346 (25.4%). The commonest organism identified was Pseudomonas aeruginosa (30.6%) followed by Acinetobacter and Candida albican (13.6% each).

Antibiotic perturbation of the preterm infant gut microbiome and resistome

The gut microbiota plays important roles in nutrient absorption, immune system development, and pathogen colonization resistance. Perturbations early in life may be detrimental to host health in the short and the long-term. Antibiotics are among the many factors that influence the development of the microbiota. Because antibiotics are heavily administered during the first critical years of gut microbiota development, it is important to understand the effects of these interventions. Infants, particularly those born prematurely, represent an interesting population because they receive early and often extensive antibiotic therapy in the first months after birth. Gibson et al. recently demonstrated that antibiotic therapy in preterm infants can dramatically affect the gut microbiome. While meropenem, ticarcillin-clavulanate, and cefotaxime treatments were associated with decreased species richness, gentamicin and vancomycin had variable effects on species richness. Interestingly, the direction of species richness response could be predicted based on the abundance of 2 species and 2 genes in the microbiome prior to gentamicin or vancomycin treatment. Nonetheless, all antibiotic treatments enriched the presence of resistance genes and multidrug resistant organisms. Treatment with different antibiotics further resulted in unique population shifts of abundant organisms and selection for different sets of resistance genes. In this addendum, we provide an extended discussion of these recent findings, and outline important future directions for elucidating the interplay between antibiotics and preterm infant gut microbiota development.

Infections and Extracorporeal Membrane Oxygenation: Incidence, Therapy, and Outcome

The objective is to assess the influence of infections and the microbiological spectrum on the general outcome of patients undergoing therapy with extracorporeal devices (ECDs), extracorporeal membrane oxygenation, extracorporeal life support, and pumpless extracorporeal lung assist. We performed a single-center, retrospective analysis of 99 patients receiving ECD. Infections requiring ECD, nosocomial infections occurring during treatment, the use of guideline-based antiinfective therapies, and patient outcomes were described and statistically analyzed. We analyzed 88 patients-survivors and nonsurvivors-and subdivided the infections into primary and nosocomial infections. The median patient age was 54.0 years, 85.2% were men, and 45 (51.1%) survived. Surviving ECD patients had a higher risk of nosocomial infection because of their prolonged hospital stay. Our results indicated that early, focused, antiinfective therapy was important to avoid severe infection complications. Infections causing sepsis and multiorgan dysfunction were negatively associated with outcome and successful weaning of ECD. The percentages and types of pathogens in the ECD cohort did not differ from the general colonization of intensive care units. Because a significant correlation between pathogens, infections, and outcome was not detected, we recommend focusing on clinical parameters to decide whether patients will benefit from ECD support.

Evaluation of the New Centers for Disease Control and Prevention Ventilator-Associated Event Module and Criteria in Critically Ill Children in Greece

OBJECTIVE To evaluate the new adult Centers for Disease Control and Prevention (CDC) ventilator-associated event (VAE) module in critically ill children and compare with the traditionally used CDC definition for ventilator-associated pneumonia (VAP). DESIGN Retrospective observational study of mechanically ventilated children in a pediatric intensive care unit in Greece January 1-December 31, 2011. METHODS Assessment of new adult CDC VAE module including 3 definition tiers: ventilator-associated condition (VAC), infection-related VAC, and possible/probable ventilator-associated pneumonia (VAE-VAP); comparison with traditional CDC criteria for clinically defined pneumonia in mechanically ventilated children (PNEU-VAP). We recorded Pediatric Risk of Mortality score at admission (PRISM III), number of ventilator-days, and outcome. RESULTS Among 119 patients with mechanical ventilation (median [range] number of ventilator-days, 7 [1-183]), 19 patients experienced VAC. Criteria for VAE-VAP were fulfilled in 12 of 19 patients with VAC (63%). Children with either VAC or VAE-VAP were on ventilation more days than patients without these conditions (16.5 vs 5 d, P=.0006 and 18 vs 5 d, P<.001, respectively), whereas PRISM-III score was similar between them. Mortality was significant higher in patients with new VAE-VAP definition (50%), but not in patients with VAC (31.6%), than the patients without new VAE-VAP (14%, P=.007) or VAC (15%, P=.1), respectively. No significant association was found between PNEU-VAP and death. Incidences of PNEU-VAP and VAE-VAP were similar, but the agreement was poor. CONCLUSIONS VAE-VAP and PNEU-VAP found similar prevalence in critically ill children but with poor agreement. However, excess of death was significantly associated only with VAE-VAP. Infect Control Hosp Epidemiol 2016:1-5.

Ventilator-associated pneumonia rates in critical care units in 3 Arabian Gulf countries: A 6-year surveillance study

BACKGROUND

Data estimating the rates of ventilator-associated pneumonia (VAP) in critical patients in Gulf Cooperation Council (GCC) countries are very limited. The aim of this study was to estimate VAP rates in GCC hospitals and to compare rates with published reports of the U.S. National Healthcare Safety Network (NHSN) and International Nosocomial Infection Control Consortium (INICC).

METHODS

VAP rates and ventilator utilization between 2008 and 2013 were calculated from aggregate VAP surveillance data using NHSN methodology pooled from 6 hospitals in 3 GCC countries: Saudi Arabia, Oman, and Bahrain. The standardized infection ratios of VAP in GCC hospitals were compared with published reports of the NHSN and INICC.

RESULTS

A total of 368 VAP events were diagnosed during a 6-year period covering 76,749 ventilator days and 134,994 patient days. The overall VAP rate was 4.8 per 1,000 ventilator days (95% confidence interval, 4.3-5.3), with an overall ventilator utilization of 0.57. The VAP rates showed a wide variability between different types of intensive care units (ICUs) and were decreasing over time. After adjusting for the differences in ICU type, the risk of VAP in GCC hospitals was 217% higher than NHSN hospitals and 69% lower than INICC hospitals.

CONCLUSIONS

The risk of VAP in ICU patients in GCC countries is higher than pooled U.S. VAP rates but lower than pooled rates from developing countries participating in the INICC.

207-nm UV Light-A Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. II: In-Vivo Safety Studies

BACKGROUND

UVC light generated by conventional germicidal lamps is a well-established anti-microbial modality, effective against both bacteria and viruses. However, it is a human health hazard, being both carcinogenic and cataractogenic. Earlier studies showed that single-wavelength far-UVC light (207 nm) generated by excimer lamps kills bacteria without apparent harm to human skin tissue in vitro. The biophysical explanation is that, due to its extremely short range in biological material, 207 nm UV light cannot penetrate the human stratum corneum (the outer dead-cell skin layer, thickness 5-20 μm) nor even the cytoplasm of individual human cells. By contrast, 207 nm UV light can penetrate bacteria and viruses because these cells are physically much smaller.

AIMS

To test the biophysically-based hypothesis that 207 nm UV light is not cytotoxic to exposed mammalian skin in vivo.

METHODS

Hairless mice were exposed to a bactericidal UV fluence of 157 mJ/cm2 delivered by a filtered Kr-Br excimer lamp producing monoenergetic 207-nm UV light, or delivered by a conventional 254-nm UV germicidal lamp. Sham irradiations constituted the negative control. Eight relevant cellular and molecular damage endpoints including epidermal hyperplasia, pre-mutagenic UV-associated DNA lesions, skin inflammation, and normal cell proliferation and differentiation were evaluated in mice dorsal skin harvested 48 h after UV exposure.

RESULTS

While conventional germicidal UV (254 nm) exposure produced significant effects for all the studied skin damage endpoints, the same fluence of 207 nm UV light produced results that were not statistically distinguishable from the zero exposure controls.

CONCLUSIONS

As predicted by biophysical considerations and in agreement with earlier in vitro studies, 207-nm light does not appear to be significantly cytotoxic to mouse skin. These results suggest that excimer-based far-UVC light could potentially be used for its anti-microbial properties, but without the associated hazards to skin of conventional germicidal UV lamps.

Hydroxyapatite microporous bioceramics as vancomycin reservoir: Antibacterial efficiency and biocompatibility investigation

AbstarctInfections after bone reconstructive surgery are a real therapeutic and economic issue for the modern health care system. As the pathogen (most often Staphylococcus aureus) is able to develop a biofilm inside the bone, local delivery of antibiotics is of interest since high drug concentrations would be delivered directly at the target place. In this context, this study evaluated a porous hydroxyapatite implant as biocompatible bone substitute and vancomycin-delivery system to prevent post-operative infections. A simple method of impregnation with optimised conditions insured a high antibiotic loading (up to 2.3 ± 0.3 mg/m²), with a complete in vitro release obtained within 1-5 days. Additionally, the bacteriostatic and bactericidal effects of vancomycin were retained after loading on hydroxyapatite, as demonstrated after challenge with a Staphylococcus aureus strain. Regarding the biocompatibility, a wound healing assay of pre-osteoblastic MC3T3-E1 cells exposed to various concentrations of vancomycin revealed a dose-dependent reduction in cell migration for antibiotic concentrations higher than 1 mg/mL. Meanwhile, cells were able to proliferate normally on vancomycin-loaded scaffolds, although cell initial adhesion was seriously impaired for scaffolds loaded with 2.3 mg/m² Loaded scaffolds could be stored up to three months at room temperature without any degradation of the antibiotic. Together, these results demonstrate the efficacy of these hydroxyapatite bone substitutes for local delivery of vancomycin in the context of bone infection.

Sources of sporadic Pseudomonas aeruginosa colonizations/infections in surgical ICUs: Association with contaminated sink trap

BACKGROUND

Many studies have reported the hospital outbreaks of Pseudomonas aeruginosa due to cross-contamination between patients and water fittings, but the importance of water fittings as sources of sporadic P. aeruginosa colonizations/infections remains ambiguous.

AIM

To investigate the sources of sporadic P. aeruginosa colonizations/infections in a clinical intensive surveillance, and further analysis the potential of sink trap for P. aeruginosa transmission in intensive care units (ICUs).

METHODS

Patients monitoring and targeted environmental screening for P. aeruginosa was performed prospectively over a 27-week period, in absence of recognized outbreak, in two surgical intensive care units (SICUs). All isolates were genotyped by Pulsed field gel electrophoresis analysis.

FINDINGS

18.9% (46/244) of water fitting samples harbored P. aeruginosa, and active screening samples from 9.2% (55/595) of hospitalized patients carried with P. aeruginosa. According to genotype results, approximately 50% of P. areuginosa colonizations/infections of patients were of exogenous origin. 64.7% (11/17) of exogenous sourced cases were associated with contaminated sink traps. There was a significant correlation between the incidence of exogenous colonization/infection and the prevalence of P. areuginosa in water fitting in SICU-2 (rs = 0.972; p = 0.014). Furthermore, P. areuginosa from sink trap possessed a higher level of resistance to multi-antibiotics as opposed to cross-transmission from other patients.

CONCLUSION

Water fitting especially sink trap act as an important role in sporadic P. aeruginosa transmission in SICU patients. This report highlights the necessity of identification of potential environmental reservoirs, such as sinks, for control of infections of environmentally hardy multi-resistant P. areuginosa.

Assessing the Burden of Healthcare-Associated Infections through Prevalence Studies: What Is the Best Method?

Objective.

To explore differences in the prevalence of healthcare-associated infections (HAIs) according to survey methodology.

Design.

Repeated point and period prevalence survey strategies.

Setting.

University-affiliated primary and tertiary care center.

Methods.

Analysis of data collected from 2006 to 2012 from annual HAI prevalence surveys using definitions proposed by the US Centers for Disease Control and Prevention. The study design allowed the analysis of the same data in the format of a point or a period prevalence survey.

Results.

Pooled point and period HAI prevalence was 7.46% and 9.84% (+32%), respectively. This additional 32% was mainly attributable to infections of the lower respiratory tract (2.42% vs 3.20% [+32%]) and the urinary tract (1.76% vs 2.62% [+49%]). Differences in surgical site infections (1.02% vs 1.20% [+19%]) and bloodstream infections (0.76% vs 0.86% [+13%]) were smaller. HAI prevalence for the point and period methodology in acute and long-term care were 7.47% versus 9.38 (+26%) and 8.37% versus 11.89% (+42%), respectively. Differences were stable over time. Focusing on the 4 major HAIs (respiratory tract, urinary tract, surgical site, and bloodstream infections) misses one-quarter of all HAIs.

Conclusions.

More HAIs are identified by the period prevalence method, especially those of shorter duration (lower respiratory and urinary tract), which would make this method more suitable to be used in long-term care. Results of the 2 study methods cannot be benchmarked against each other.

Infect Control Hosp Epidemiol2014;35(6):674–684

Clinical significance of ventilator-associated event

PURPOSE

A novel surveillance algorithm of ventilator-associated event (VAE) was introduced to overcome the subjectivity of conventional ventilator-associated pneumonia. We investigated the risk factors and prognostic values of VAE.

METHODS

We conducted a retrospective study of 869 patients treated with mechanical ventilation for greater than or equal to 2 calendar days from January 2013 to June 2014. We compared the episodes of mechanical ventilation with or without VAE and analyzed risk factors and clinical outcomes of VAE.

RESULTS

Among 1031 episodes of mechanical ventilation, 92 episodes were complicated with VAE. VAE occurred more frequently when the initial causes of mechanical ventilation were trauma (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.1-6.3) and pulmonary edema (OR, 2.4; 95% CI, 1.2-4.7). VAE was significantly associated with prolonged mechanical ventilation (5 vs 12 days; P<.001), reduced rate of successful extubation (50.1% vs 17.5%; P<.001), and increased 30-day mortality (35.6% vs 74.2%; P<.001). VAE was a significant risk factor of 30-day mortality on multivariate regression analysis (OR, 3.6; 95% CI, 2.0-6.6; P<.001).

CONCLUSIONS

Patients treated with mechanical ventilation due to pulmonary edema or trauma had increased risk of VAE, with its development indicative of adverse clinical outcomes.

Impact of ventilator-associated pneumonia on mortality and epidemiological features of patients with secondary peritonitis

Background

Despite the significant impact of nosocomial infections on the morbidity and mortality of patients staying in the intensive care unit (ICU), no study over the past 20 years has focused specifically on VAP following secondary peritonitis. The objective of the present study was to determine in-hospital mortality and epidemiological features attributed to ventilator-associated pneumonia (VAP) following secondary peritonitis.

Methods

Prospective observational study involved 418 consecutive patients admitted in the ICU. Univariate and multivariate analyses were performed to identify risk factors associated with mortality and development of VAP.

Results

The incidence of VAP following secondary peritonitis was 9.6 %. Risk factors associated with the development of VAP were hospital-acquired peritonitis, requiring >48 h of mechanical ventilation, and SOFA score. The onset of VAP was late in majority of patients. VAP was developed about 16.8 days after the initiation of the peritonitis. Etiological microorganisms responsible for the peritonitis were different than for VAP. The 90-day in-hospital mortality rate was 47.5 % of VAP patients. Independent factors associated with 30- to 90-day in-hospital mortality were VAP and SOFA.

Conclusions

In light of the impact on morbidity and mortality in the ICU, more attention should be given to the concurrent features among VAP and secondary peritonitis.

The Centers for Disease Control and Prevention definition of mucosal barrier injury-associated bloodstream infection improves accurate detection of preventable bacteremia rates at a pediatric cancer center in a low- to middle-income country

BACKGROUND

The US National Healthcare Safety Network has provided a definition of mucosal barrier injury-associated, laboratory-confirmed bloodstream infection (MBI-LCBI) to improve infection surveillance. To date there is little information about its influence in pediatric oncology centers in low- to middle-income countries.

OBJECTIVES

To determine the influence of the definition on the rate of central line-associated bloodstream infection (CLABSI) and compare the clinical characteristics of MBI versus non-MBI LCBI cases.

METHODS

We retrospectively applied the National Healthcare Safety Network definition to all CLABSIs recorded at a pediatric oncology center in Tijuana, Mexico, from January 2011 through December 2014. CLABSI events were reclassified according to the MBI-LCBI definition. Clinical characteristics and outcomes of MBI and non-MBI CLABSIs were compared.

RESULTS

Of 55 CLABSI events, 44% (24 out of 55) qualified as MBI-LCBIs; all were MBI-LCBI subcategory 1 (intestinal flora pathogens). After the number of MBI-LCBI cases was removed from the numerator, the CLABSI rate during the study period decreased from 5.72-3.22 infections per 1,000 central line days. Patients with MBI-LCBI were significantly younger than non-MBI-LCBI patients (P = .029) and had a significantly greater frequency of neutropenia (100% vs 39%; P = .001) and chemotherapy exposure (87% vs 58%; P = .020) and significantly longer median hospitalization (34 vs 23 days; P = .008).

CONCLUSION

A substantial proportion of CLABSI events at our pediatric cancer center met the MBI-LCBI criteria. Our results support separate monitoring and reporting of MBI and non-MBI-LCBIs in low- to middle-income countries to allow accurate detection and tracking of preventable (non-MBI) bloodstream infections.

Application of Pharmacodynamic Profiling for the Selection of Optimal β-lactam Regimens in a Large University Hospital

BACKGROUND

Infections caused by drug-resistant Gram-negative bacteria (GNB) are increasing worldwide and as a result, the selection of appropriate empiric antibiotics (ATBs) has been made increasingly difficult. The present study aimed to identify optimized dosing regimens of intravenous (IV) ATBs, defined by cumulative fraction response (CFR), against E. coli (EC), K. pneumoniae (KP), P. aeruginosa (PA), and A. baumannii (AB) at 2,300-bed University Hospital.

MATERIALS AND METHODS

The minimum inhibitory concentrations (MIC) of EC, KP, PA, and AB from clinical specimens, 250 each, were determined. Pharmacodynamic profiling using Monte Carlo Simulation was performed for standard, high dosage, and prolonged infusions (PI) of ceftriaxone, cefepime, ceftazidime, imipenem, meropenem, and doripenem. A CFR of ≥90% was targeted as providing a sufficiently high ATB exposure.

RESULTS

When considering the Enterobacteriaceae, the % susceptible for the cephalosporins ranged from 60% for ceftriaxone to 86% for cefepime, as a result only the 2g q8h regimens of ceftazidime and cefepime provided high CFRs. In contrast, all the carbapenems had % susceptible and CFRs ≥90% for EC and KP. While cefepime and ceftazidime demonstrated higher % susceptibility (82-83%) for PA relative to that of the carbapenems (61-69%) only doripenem 2g q8h (4h PI) achieved an optimal CFR (92%) against this organism. Due to the MIC profiles and dismal susceptibilities of AB (16-22%), none of the regimens studied achieved CFRs > 65%.

CONCLUSIONS

The pharmacodynamic profiling undertaken in the current study provides insights that allow prescribers to select more appropriate empirical antibiotic regimens for the treatment of infection caused by these common GNB pathogens at this Thai hospital. While higher doses and PI of β-lactams improve exposures against EC, KP and PA, this approach will not sufficiently enhance their potency against AB, thus alternative therapies should be considered for this organism.

Developmental dynamics of the preterm infant gut microbiota and antibiotic resistome

Development of the preterm infant gut microbiota is emerging as a critical research priority(1). Since preterm infants almost universally receive early and often extended antibiotic therapy(2), it is important to understand how these interventions alter gut microbiota development(3-6). Analysis of 401 stools from 84 longitudinally sampled preterm infants demonstrates that meropenem, cefotaxime and ticarcillin-clavulanate are associated with significantly reduced species richness. In contrast, vancomycin and gentamicin, the antibiotics most commonly administered to preterm infants, have non-uniform effects on species richness, but these can be predicted with 85% accuracy based on the relative abundance of only two bacterial species and two antibiotic resistance (AR) genes at treatment initiation. To investigate resistome development, we functionally selected resistance to 16 antibiotics from 21 faecal metagenomic expression libraries. Of the 794 AR genes identified, 79% had not previously been classified as AR genes. Combined with deep shotgun sequencing of all stools, we find that multidrug-resistant members of the genera Escherichia, Klebsiella and Enterobacter, genera commonly associated with nosocomial infections, dominate the preterm infant gut microbiota. AR genes that are enriched following specific antibiotic treatments are generally unique to the specific treatment and are highly correlated with the abundance of a single species. The most notable exceptions include ticarcillin-clavulanate and ampicillin, both of which enrich for a large number of overlapping AR genes, and are correlated with Klebsiella pneumoniae. We find that all antibiotic treatments are associated with widespread collateral microbiome impact by enrichment of AR genes that have no known activity against the specific antibiotic driver.

Multicenter study of device-associated infection rates in hospitals of Mongolia: Findings of the International Nosocomial Infection Control Consortium (INICC)

BACKGROUND

To report the results of the International Nosocomial Infection Control Consortium (INICC) multicenter study conducted in Mongolia from September 2013-March 2015.

METHODS

A device-associated health care-associated infection prospective surveillance study in 3 adult intensive care units (ICUs) from 3 hospitals using the U.S. Centers for Disease Control and Prevention (CDC) and National Healthcare Safety Network (NHSN) definitions and INICC methods.

RESULTS

We documented 467 ICU patients for 2,133 bed days. The central line-associated bloodstream infection (CLABSI) rate was 19.7 per 1,000 central line days, the ventilator-associated pneumonia (VAP) rate was 43.7 per 1,000 mechanical ventilator days, and the catheter-associated urinary tract infection (CAUTI) rate was 15.7 per 1,000 urinary catheter days; all of the rates are higher than the INICC rates (CLABSI: 4.9; VAP: 16.5; and CAUTI: 5.3) and CDC-NHSN rates (CLABSI: 0.8; VAP: 1.1; and CAUTI: 1.3). Device use ratios were also higher than the CDC-NHSN and INICC ratios, except for the mechanical ventilator device use ratio, which was lower than the INICC ratio. Resistance of Staphylococcus aureus to oxacillin was 100%. Extra length of stay was 15.1 days for patients with CLABSI, 7.8 days for patients with VAP, and 8.2 days for patients with CAUTI. Extra crude mortality in the ICUs was 18.6% for CLABSI, 17.1% for VAP, and 5.1% for CAUTI.

CONCLUSION

Device-associated health care-associated infection rates and most device use ratios in our Mongolian hospitals' ICUs are higher than the CDC-NSHN and INICC rates.

Catheter-associated urinary tract infection after cardiovascular surgery: Impact of a multifaceted intervention

BACKGROUND

The aims of this study were to assess the impact of a multifaceted intervention on the incidence of catheter-associated urinary tract infection (CAUTI) and on the urinary catheter utilization (UCU) ratio, evaluating adherence to recommendations for the use of indwelling urinary catheters (IUCs).

METHODS

This prospective, before-and-after interventional study was conducted in three 6-month phases: preintervention (phase 1), intervention (phase 2), and postintervention (phase 3). We observed IUC insertion technique, maintenance care, and removal/nonremoval practices; provided training on CAUTI prevention measures; evaluated professional knowledge; provided adherence feedback; determined the incidence of CAUTI, and calculating the UCU ratio.

RESULTS

Between phases 1 and 3, CAUTI incidence fell from 11.42 to 4.40 cases/1000 catheter-days (P = .216), whereas the UCU ratio remained constant. The risk of CAUTI was 2.6-fold higher in phase 1 than in phase 3. Adherence to hand hygiene (before and after IUC insertion) improved significantly, as did adherence to attaching the IUC to the patient and maintenance care guidelines. The reasons for IUC use (including inappropriate reasons) did not differ significantly. Professional knowledge improved significantly after training.

CONCLUSION

A multifaceted intervention effectively reduced CAUTI incidence and improved the quality of care.

Potential Cost-effectiveness of Early Identification of Hospital-acquired Infection in Critically Ill Patients

RATIONALE

Limitations in methods for the rapid diagnosis of hospital-acquired infections often delay initiation of effective antimicrobial therapy. New diagnostic approaches offer potential clinical and cost-related improvements in the management of these infections.

OBJECTIVES

We developed a decision modeling framework to assess the potential cost-effectiveness of a rapid biomarker assay to identify hospital-acquired infection in high-risk patients earlier than standard diagnostic testing.

METHODS

The framework includes parameters representing rates of infection, rates of delayed appropriate therapy, and impact of delayed therapy on mortality, along with assumptions about diagnostic test characteristics and their impact on delayed therapy and length of stay. Parameter estimates were based on contemporary, published studies and supplemented with data from a four-site, observational, clinical study. Extensive sensitivity analyses were performed. The base-case analysis assumed 17.6% of ventilated patients and 11.2% of nonventilated patients develop hospital-acquired infection and that 28.7% of patients with hospital-acquired infection experience delays in appropriate antibiotic therapy with standard care. We assumed this percentage decreased by 50% (to 14.4%) among patients with true-positive results and increased by 50% (to 43.1%) among patients with false-negative results using a hypothetical biomarker assay. Cost of testing was set at $110/d.

MEASUREMENTS AND MAIN RESULTS

In the base-case analysis, among ventilated patients, daily diagnostic testing starting on admission reduced inpatient mortality from 12.3 to 11.9% and increased mean costs by $1,640 per patient, resulting in an incremental cost-effectiveness ratio of $21,389 per life-year saved. Among nonventilated patients, inpatient mortality decreased from 7.3 to 7.1% and costs increased by $1,381 with diagnostic testing. The resulting incremental cost-effectiveness ratio was $42,325 per life-year saved. Threshold analyses revealed the probabilities of developing hospital-acquired infection in ventilated and nonventilated patients could be as low as 8.4 and 9.8%, respectively, to maintain incremental cost-effectiveness ratios less than $50,000 per life-year saved.

CONCLUSIONS

Development and use of serial diagnostic testing that reduces the proportion of patients with delays in appropriate antibiotic therapy for hospital-acquired infections could reduce inpatient mortality. The model presented here offers a cost-effectiveness framework for future test development.

Perceptions and Practices of Community Pharmacists towards Antimicrobial Stewardship in the State of Selangor, Malaysia

Background

Increasing antimicrobial resistance is one of the pressing concerns globally. Injudicious use of antibiotics is one of the modifiable factors responsible for antimicrobial resistance. Given the widespread use of antimicrobials in community settings, pharmacists have an important role in ensuring appropriate use of antibiotics. The objective of this study was to assess the perception and self-reported practices of community pharmacists towards antimicrobial stewardship.

Methods

A cross-sectional study was conducted among community pharmacists between March–April, 2015, using a self-administered, pre-tested questionnaire in the State of Selangor, Malaysia. A simple random sampling approach was used to select pharmacy sites. Descriptive and inferential statistical methods were used to analyse the data.

Results

A total of 188 pharmacists responded to the survey, giving a response rate of 83.5%. The majority of participants (n = 182, 96.8%) believed that antimicrobial stewardship program helps healthcare professionals to improve the quality of patient care. However, more than half of pharmacists were neutral in their opinion about the incorporation of antimicrobial stewardship programs in community pharmacies (n = 102, 54.2%). Though collaboration was often done by pharmacists with other health professionals over the use of antibiotics (n = 104, 55.3%), a significant proportion of participants (n = 102, 54.2%) rarely/occasionally participate in antimicrobial awareness campaigns. Pharmacists having postgraduate qualification were more likely to held positive perceptions of, and were engaged in, antimicrobial stewardship than their non-postgraduate counterpart (p<0.05). Similarly, more experienced pharmacists (> 10 years) held positive perceptions towards antimicrobial stewardship (p<0.05).

Conclusion

The study highlighted some gaps in the perception and practices of community pharmacist towards antimicrobial stewardship. Development of customized interventions would be critical to bridging these gaps and improve their perception and practices towards antimicrobial stewardship.

Antibiotic-Resistant Acinetobacter baumannii Increasing Success Remains a Challenge as a Nosocomial Pathogen

Antibiotic-resistant infectious bacteria currently imply a high risk and therefore constitute a strong challenge when treating patients in hospital settings. Characterization of these species and of particular strains is a priority for the establishment of diagnostic tests and preventive procedures. The relevance of Acinetobacter baumannii as a problematic microorganism in inpatient facilities, particularly intensive care units, has increased over time. This review aims to draw attention to (i) the historical emergence of carbapenem-resistant Acinetobacter baumannii, (ii) the current status of surveillance needs in Latin America, and (iii) recent data suggesting that A. baumannii continues to spread and evolve in hospital settings. First, we present synopsis of the series of events leading to the discovery and precise identification of this microorganism in hospital settings. Then key events in the acquisition of antibiotic-resistant genes by this microorganism are summarized, highlighting the race between new antibiotic generation and emergence of A. baumannii resistant strains. Here we review the historical development of this species as an infectious threat, the current state of its distribution, and antibiotic resistance characteristics, and we discuss future prospects for its control.

Sonodynamic action of hypocrellin B on methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) commonly causes refractory infections and has recently become a serious public health concern. The present study was designed to investigate sonodynamic action of hypocrellin B on MRSA. A MRSA strain (ATCC BAA-43) was used in the present study. The dark toxicity of hypocrellin B on MRSA and its uptake in MRSA first were measured. And then bacteria were incubated with hypocrellin B and exposed to ultrasound. After sonodynamic treatment, colony forming unit assay and bacterial viability assay were conducted. Membrane permeability assay, DNA fragmentation assay, and DNA synthesis assay were also performed to examine the underlying mechanism. The results showed that hypocrellin B at concentrations of up to 500 μM had no toxicity to MRSA in the dark. After incubation for 50 min, hypocrellin B could be maximally absorbed by MRSA, and exhibited significant sonodynamic activity in a dose-dependent manner. The 5-log reduction in colony forming unit (CFU) was observed after hypocrellin B (40 μM) treatment at an intensity of 1.38 W/cm(2) ultrasound for 5 min. Compared to the control, hypocrellin B alone and ultrasound sonication alone group, more dead cells were found and bacterial membrane integrity was notably damaged after sonodynamic treatment of hypocrellin B. However, no remarkable DNA damage was found in MRSA after sonodynamic treatment of hypocrellin B. All the findings demonstrated that hypocrellin B could serve as a potential antibacterial sonosensitizer to significantly cause damage to the membrane integrity of MRSA and inhibit its growth under ultrasound sonication.

Burden of Hospital Acquired Infections and Antimicrobial Use in Vietnamese Adult Intensive Care Units

Background

Vietnam is a lower middle-income country with no national surveillance system for hospital-acquired infections (HAIs). We assessed the prevalence of hospital-acquired infections and antimicrobial use in adult intensive care units (ICUs) across Vietnam.

Methods

Monthly repeated point prevalence surveys were systematically conducted to assess HAI prevalence and antimicrobial use in 15 adult ICUs across Vietnam. Adults admitted to participating ICUs before 08:00 a.m. on the survey day were included.

Results

Among 3287 patients enrolled, the HAI prevalence was 29.5% (965/3266 patients, 21 missing). Pneumonia accounted for 79.4% (804/1012) of HAIs Most HAIs (84.5% [855/1012]) were acquired in the survey hospital with 42.5% (363/855) acquired prior to ICU admission and 57.5% (492/855) developed during ICU admission. In multivariate analysis, the strongest risk factors for HAI acquired in ICU were: intubation (OR 2.76), urinary catheter (OR 2.12), no involvement of a family member in patient care (OR 1.94), and surgery after admission (OR 1.66). 726 bacterial isolates were cultured from 622/1012 HAIs, most frequently Acinetobacter baumannii (177/726 [24.4%]), Pseudomonas aeruginosa (100/726 [13.8%]), and Klebsiella pneumoniae (84/726 [11.6%]), with carbapenem resistance rates of 89.2%, 55.7%, and 14.9% respectively. Antimicrobials were prescribed for 84.8% (2787/3287) patients, with 73.7% of patients receiving two or more. The most common antimicrobial groups were third generation cephalosporins, fluoroquinolones, and carbapenems (20.1%, 19.4%, and 14.1% of total antimicrobials, respectively).

Conclusion

A high prevalence of HAIs was observed, mainly caused by Gram-negative bacteria with high carbapenem resistance rates. This in combination with a high rate of antimicrobial use illustrates the urgent need to improve rational antimicrobial use and infection control efforts.

Antimicrobial Activity of Bacillus amyloliquefaciens ANT1 Toward Pathogenic Bacteria and Mold: Effects on Biofilm Formation

The intensive use and misuse of antibiotics over the last decades have generated a strong selective pressure for the emergence of multi-resistant strains and nosocomial infections. Biofilm has been demonstrated as a key parameter in spreading infections, especially in hospitals and healthcare units. Therefore, the development of novel anti-biofilm drugs is actually of the upmost importance. Here, the antimicrobial and antibiofilm activities toward pathogenic microorganisms of a set of non-ribosomal synthesized peptides and polyketides isolated from Bacillus amyloliquefaciens ANT1 culture supernatant are presented.

Colonization and infection with extended-spectrum β-lactamase-producing Enterobacteriaceae in ICU patients: what impact on outcomes and carbapenem exposure?

OBJECTIVES

It remains uncertain whether colonization and infection with ESBL-producing Enterobacteriaceae (ESBL-PE) affect the outcomes for ICU patients. Our objectives were to measure the effects of ESBL-PE carriage and infection on mortality, ICU length of stay (LOS) and carbapenem exposure in this population.

METHODS

A cause-specific hazard model based on prospectively collected data was built to assess the impact of ESBL-PE colonization and infection on competing risks of death and ICU discharge at day 28 in a multicentre cohort of ICU patients. Carbapenem exposure during the ICU stay was compared between infected carriers, uninfected carriers and non-carriers.

RESULTS

Among the 16,734 included patients, 594 (3.5%) were ESBL-PE carriers, including 98 (16.4%) with one or more ESBL-PE infections during the ICU stay. After adjustment for baseline and time-dependent confounders, ESBL-PE infections increased the probability of death at day 28 [adjusted cause-specific hazard ratio (aCSHR), 1.825, 95% CI 1.235-2.699, P = 0.0026] and the ICU LOS (aCSHR for discharge alive at day 28, 0.563, 95% CI 0.432-0.733, P < 0.0001). ESBL-PE carriage without infection extended the LOS (aCSHR, 0.623, 95% CI, 0.553-0.702, P < 0.0001), without affecting mortality (aCSHR, 0.906, 95% CI, 0.722-1.136, P = 0.3916). Carbapenem exposure increased in both infected and uninfected carriers when compared with non-carriers (627, 241 and 69 carbapenem days per 1000 patient days, respectively, P < 0.001).

CONCLUSIONS

ESBL-PE infections increased carbapenem consumption, LOS and day 28 mortality. ESBL-PE infections were rather infrequent in carriers; however, even ESBL-PE carriage without infection increased carbapenem exposure and delayed discharge, thereby amplifying the selective pressure and the colonization pressure in the ICU.

207-nm UV Light-A Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. II: In-Vivo Safety Studies

BACKGROUND

UVC light generated by conventional germicidal lamps is a well-established anti-microbial modality, effective against both bacteria and viruses. However, it is a human health hazard, being both carcinogenic and cataractogenic. Earlier studies showed that single-wavelength far-UVC light (207 nm) generated by excimer lamps kills bacteria without apparent harm to human skin tissue in vitro. The biophysical explanation is that, due to its extremely short range in biological material, 207 nm UV light cannot penetrate the human stratum corneum (the outer dead-cell skin layer, thickness 5-20 μm) nor even the cytoplasm of individual human cells. By contrast, 207 nm UV light can penetrate bacteria and viruses because these cells are physically much smaller.

AIMS

To test the biophysically-based hypothesis that 207 nm UV light is not cytotoxic to exposed mammalian skin in vivo.

METHODS

Hairless mice were exposed to a bactericidal UV fluence of 157 mJ/cm2 delivered by a filtered Kr-Br excimer lamp producing monoenergetic 207-nm UV light, or delivered by a conventional 254-nm UV germicidal lamp. Sham irradiations constituted the negative control. Eight relevant cellular and molecular damage endpoints including epidermal hyperplasia, pre-mutagenic UV-associated DNA lesions, skin inflammation, and normal cell proliferation and differentiation were evaluated in mice dorsal skin harvested 48 h after UV exposure.

RESULTS

While conventional germicidal UV (254 nm) exposure produced significant effects for all the studied skin damage endpoints, the same fluence of 207 nm UV light produced results that were not statistically distinguishable from the zero exposure controls.

CONCLUSIONS

As predicted by biophysical considerations and in agreement with earlier in vitro studies, 207-nm light does not appear to be significantly cytotoxic to mouse skin. These results suggest that excimer-based far-UVC light could potentially be used for its anti-microbial properties, but without the associated hazards to skin of conventional germicidal UV lamps.

Effect of two different feeding methods on preventing ventilator associated pneumonia in the paediatric intensive care unit (PICU): A randomised controlled study

BACKGROUND

For infants and children who require intubation in the paediatric intensive care unit (PICU), ventilator-associated pneumonia (VAP) is a significant cause of secondary morbidity and mortality linked with extended use of intubation. Nurses are primarily responsible for the prevention of VAP and there are a number of procedures that contribute towards this end. Although enteral nutrition has been reported to be effective in the prevention of VAP, this remains controversial.

OBJECTIVE

To compare and evaluate the effects of intermittent feeding through a nasogastric catheter with those of continuous feeding through a nasoduodenal catheter in preventing VAP in the PICU.

DESIGN

The research design was a randomised, controlled experimental study.

METHODS

Forty paediatric patients were randomised and divided into two groups of 20: one group for nasoduodenal (ND) feeding and the other for nasogastric (NG) feeding. Patients were assessed for the development of VAP using the clinical pulmonary infection score and Centers for Disease Control and Prevention criteria while working in accordance with the VAP prevention bundles introduced within the unit.

RESULTS

The incidence of paediatric VAP was 15%. The rate of VAP in patients who were ND fed was 10%, whereas the rate of VAP in patients who had NG feeding was 20%. No statistically significant difference was observed between the ND- and NG-fed patients (p=0.661).

CONCLUSION

Although the results of our study were not statistically significant, nasoduodenal feeding helped to reduce the incidence of VAP.

Epidemiological study of prevalence, determinants, and outcomes of infections in medical ICU at a tertiary care hospital in India

OBJECTIVES

To determine the prevalence of infections, risk factors, and outcomes in a medical intensive care unit (ICU), we performed a hospital-based study.

MATERIALS AND METHODS

Consecutive patients were enrolled and details of risk factors and bacteriological data were obtained. Outcomes were death/transfer to palliative care or recovery. Statistical analyses were performed.

RESULTS

Four hundred and eighty-seven patients were admitted during the study period (age 55.6 ± 19 yr, men 68%). Diseases responsible were respiratory (37%), gastrointestinal/liver (22%), neurological (20%), renal (8%), and trauma (6%) related. Majority of admissions were direct (45%) or transfers from other hospitals (41%). Most important comorbidities were hypertension (41%), diabetes (31%), and chronic obstructive pulmonary disease (15%). Median APACHE-2 score was 13.0 (IQR 1-25). Antibiotics were administered in 98%. Bacteriological cultures were positive in 28% (n = 623). Respiratory infections were the most common (45.5%) followed by blood (23.3%) and urinary (16.1%). Gram-negative bacteria were common-Acinetobacter baumannii (20.9%), Klebsiella pneumoniae (19.7%), Escherichia coli (18.3%), and Pseudomonas aeruginosa (14.0%). There a high prevalence of resistance to common antibiotics. Patients with positive cultures were older, transferees (46 vs 37%, P = 0.07), with respiratory disease (48 vs. 33%, P = 0.003), with more than two comorbidities (33 vs 21%, P = 0.009), and higher APACHE-2 score (17.7 ± 8 vs. 13.3 ± 8, P = 0.07). Three hundred and fifty-two (72.3%) recovered, 68 (13.9%) died, and 67 (13.8%) were transferred to palliative care. Survival was associated with younger age, lower APACHE-2 score, negative cultures, and shorter duration in ICU (P < 0.05). Mortality was greater in patients with Acinetobacter (OR 2.36, 1.17-4.73), Klebsiella (OR 2.81, 1.33-5.92), Pseudomonas (OR 8.03, 2.83-22.76), or Enterobacter (OR 6.73, 1.29-35.12) infection.

CONCLUSIONS

There is high prevalence of infections in patients in a medical ICU in India. Gram-negative bacteria are the most prevalent and resistance to antibiotics is high. Risk factors are age, hospital transfers, APACHE-2 score, and multiple comorbidities.

Sent packing: protein engineering generates a new crystal form of Pseudomonas aeruginosa DsbA1 with increased catalytic surface accessibility

Pseudomonas aeruginosa is an opportunistic human pathogen for which new antimicrobial drug options are urgently sought. P. aeruginosa disulfide-bond protein A1 (PaDsbA1) plays a pivotal role in catalyzing the oxidative folding of multiple virulence proteins and as such holds great promise as a drug target. As part of a fragment-based lead discovery approach to PaDsbA1 inhibitor development, the identification of a crystal form of PaDsbA1 that was more suitable for fragment-soaking experiments was sought. A previously identified crystallization condition for this protein was unsuitable, as in this crystal form of PaDsbA1 the active-site surface loops are engaged in the crystal packing, occluding access to the target site. A single residue involved in crystal-packing interactions was substituted with an amino acid commonly found at this position in closely related enzymes, and this variant was successfully used to generate a new crystal form of PaDsbA1 in which the active-site surface is more accessible for soaking experiments. The PaDsbA1 variant displays identical redox character and in vitro activity to wild-type PaDsbA1 and is structurally highly similar. Two crystal structures of the PaDsbA1 variant were determined in complex with small molecules bound to the protein active site. These small molecules (MES, glycerol and ethylene glycol) were derived from the crystallization or cryoprotectant solutions and provide a proof of principle that the reported crystal form will be amenable to co-crystallization and soaking with small molecules designed to target the protein active-site surface.

Structural Relationship of the Lipid A Acyl Groups to Activation of Murine Toll-Like Receptor 4 by Lipopolysaccharides from Pathogenic Strains of Burkholderia mallei, Acinetobacter baumannii, and Pseudomonas aeruginosa

Toll-like receptor 4 (TLR4) is required for activation of innate immunity upon recognition of lipopolysaccharide (LPS) of Gram-negative bacteria. The ability of TLR4 to respond to a particular LPS species is important since insufficient activation may not prevent bacterial growth while excessive immune reaction may lead to immunopathology associated with sepsis. Here, we investigated the biological activity of LPS from Burkholderia mallei that causes glanders, and from the two well-known opportunistic pathogens Acinetobacter baumannii and Pseudomonas aeruginosa (causative agents of nosocomial infections). For each bacterial strain, R-form LPS preparations were purified by hydrophobic chromatography and the chemical structure of lipid A, an LPS structural component, was elucidated by HR-MALDI-TOF mass spectrometry. The biological activity of LPS samples was evaluated by their ability to induce production of proinflammatory cytokines, such as IL-6 and TNF, by bone marrow-derived macrophages. Our results demonstrate direct correlation between the biological activity of LPS from these pathogenic bacteria and the extent of their lipid A acylation.

The spread of bla OXA-48 and bla OXA-244 carbapenemase genes among Klebsiella pneumoniae, Proteus mirabilis and Enterobacter spp. isolated in Moscow, Russia

Background

The spread of carbapenemase-producing Enterobacteriaceae (CPE) is a great problem of healthcare worldwide. Study of the spread for bla_OXA-48-like genes coding epidemically significant carbapenemases among hospital pathogens is important for the regional and global epidemiology of antimicrobial resistance.

Methods

Antibacterial resistant isolates of Klebsiella pneumoniae (n = 95) from 54 patients, P.mirabilis (n = 32) from 20 patients, Enterobacter aerogenes (n = 6) from four patients, and Enterobacter cloacae (n = 4) from four patients were collected from January, 2013 to October, 2014 in neurosurgical intensive care unit (ICU) of the Burdenko Neurosurgery Institute, Moscow. Characteristics of the isolates were done using susceptibility tests, PCR detection of the resistance genes, genotyping, conjugation, DNA sequencing, and bioinformatic analysis.

Results

Major strains under study were multi drug resistant (MDR), resistant to three or more functional classes of drugs simultaneously—98.9 % K. pneumoniae, 100 % P.mirabilis, one E.aerogenes isolate, and one E.cloacae isolate. Molecular-genetic mechanism of MDR in K.pneumoniae and P.mirabilis isolates were based on carrying of epidemic extended-spectrum beta-lactamase bla_CTX-M-15 gene (87.2 and 90.6 % accordingly), carbapenemase bla_OXA-48-like gene (55.3 and 23.3 % accordingly), and class 1 (54.8 and 31.3 % accordingly) and class 2 (90.6 % P. mirabilis) integrons. The bla_OXA-48-like-positive K. pneumoniae were collected during whole two-year surveillance period, while P. mirabilis and Enterobacter spp. carrying bla_OXA-48-like genes were detected only after four and 18 months after the research start, respectively. The bla_OXA-48-like gene acquisition was shown for P. mirabilis isolates collected from five patients and for E. cloacae isolate collected from one patient during their stay in the ICU, presumably from bla_OXA-48-like-positive K. pneumoniae. The source of the bla_OXA-244 gene acquired by E. aerogenes isolates and the time of this event were not recognized.

Conclusions

The expanding of CPE in the surveyed ICU was associated with the spread of bla_OXA-48 and bla_OXA-244 carbapenemase genes documented not only among K.pneumoniae, well-known bacterial host for such genes, but among P.mirabilis, E.aerogenes, and E. cloacae.

Update on infection control challenges in special pediatric populations

PURPOSE OF REVIEW

Compared with adults, neonatal and pediatric populations are especially vulnerable patients who have specific diagnostic and therapeutic differences; therefore, the standard infection control practices designed for adults are sometimes not effective or need modifications to work. This review focuses on the recent literature addressing the challenges and successes in preventing healthcare-associated infections (HAIs) in children.

RECENT FINDINGS

Improving the implementation of pediatric versions of preventive bundles focusing on proper catheter insertion and maintenance, mainly as a part of a larger multimodal strategy, is effective in reducing the central-line-associated bloodstream infections in neonatal and pediatric populations including oncology patients. Appropriate feeding, antimicrobial stewardship, and infection control measures should be combined in reducing necrotizing enterocolitis in preterm neonates. Implementing a multimodal bundle strategy adapted for pediatric population is successful in preventing ventilator-associated pneumonia. Appropriate use of antimicrobial prophylaxis remains the cornerstone for preventing surgical-site infections irrespective of age, with few additional effective adjuvant preventive practices in specific pediatric patients.

SUMMARY

Several evidence-based practices are effective in reducing the incidence and the impact of HAIs in children; however, proper implementation remains a challenge. Additionally, several adult preventive practices are still unestablished in children and need further thorough examination.

Mechanisms of antimicrobial resistance in Gram-negative bacilli

The burden of multidrug resistance in Gram-negative bacilli (GNB) now represents a daily issue for the management of antimicrobial therapy in intensive care unit (ICU) patients. In Enterobacteriaceae, the dramatic increase in the rates of resistance to third-generation cephalosporins mainly results from the spread of plasmid-borne extended-spectrum beta-lactamase (ESBL), especially those belonging to the CTX-M family. The efficacy of beta-lactam/beta-lactamase inhibitor associations for severe infections due to ESBL-producing Enterobacteriaceae has not been adequately evaluated in critically ill patients, and carbapenems still stands as the first-line choice in this situation. However, carbapenemase-producing strains have emerged worldwide over the past decade. VIM- and NDM-type metallo-beta-lactamases, OXA-48 and KPC appear as the most successful enzymes and may threaten the efficacy of carbapenems in the near future. ESBL- and carbapenemase-encoding plasmids frequently bear resistance determinants for other antimicrobial classes, including aminoglycosides (aminoglycoside-modifying enzymes or 16S rRNA methylases) and fluoroquinolones (Qnr, AAC(6′)-Ib-cr or efflux pumps), a key feature that fosters the spread of multidrug resistance in Enterobacteriaceae. In non-fermenting GNB such as Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia, multidrug resistance may emerge following the sole occurrence of sequential chromosomal mutations, which may lead to the overproduction of intrinsic beta-lactamases, hyper-expression of efflux pumps, target modifications and permeability alterations. P. aeruginosa and A. baumannii also have the ability to acquire mobile genetic elements encoding resistance determinants, including carbapenemases. Available options for the treatment of ICU-acquired infections due to carbapenem-resistant GNB are currently scarce, and recent reports emphasizing the spread of colistin resistance in environments with high volume of polymyxins use elicit major concern.

Reducing ventilator-associated pneumonia in neonatal intensive care unit using "VAP prevention Bundle": a cohort study

BACKGROUND

Ventilator-associated pneumonia (VAP) is a serious health care-associated infection, resulting in high morbidity and mortality. It also prolongs hospital stay and drives up hospital costs. Measures employed in preventing ventilator-associated pneumonia in developing countries are rarely reported. In this study we tried to assess the efficacy of our designed "VAP prevention bundle" in reducing VAP rate in our neonatal intensive care unit (NICU).

METHOD

This prospective before-and-after study was conducted at university hospital NICU, all neonates who had mechanical ventilation for ≥ 48 h were eligible. VAP rates were evaluated before (phase-I) and after (phase-II) full implementation of comprehensive preventive measures specifically designed by our infection control team.

RESULTS

Of 143 mechanically ventilated neonates, 73 patients developed VAP (51%) throughout the study period (2500 mechanical ventilation days). The rate of VAP was significantly reduced from 67.8% (42/62) corresponding to 36.4 VAP episodes/1000 mechanical ventilation days (MV days) in phase-I to 38.2% (31/81) corresponding to 23 VAP/1000 MV days (RR 0.565, 95% confidence interval 0.408-0.782, p = 0.0006) after VAP prevention bundle implementation (phase-II). Parallel significant reduction in MV days/case were documented in post-intervention period (21.50 ± 7.6 days in phase-I versus 10.36 ± 5.2 days in phase-II, p = 0.000). There were a trend toward reduction in NICU length of stay (23.9 ± 10.3 versus 22.8 ± 9.6 days, p = 0.56) and overall mortality (25% versus 17.3%, p = 0.215) between the two phases but didn't reach statistical significance. The commonest micro-organisms isolated throughout the study were gram-negative bacteria (63/66, 95.5%) particularly Klebsilla pneumonia (55/66, 83.4%).

CONCLUSION

Implementation of multifaceted infection control bundle resulted in reduction of VAP rate, length of stay in our NICU.

Central line-associated bloodstream infections among critically-ill patients in the era of bundle care

BACKGROUND/PURPOSE

Patients admitted to intensive care units (ICUs) are at high risk for central line-associated bloodstream infections (CLABSIs). Bundle care has been documented to reduce CLABSI rates in Western countries, however, few reports were from Asian countries and the differences in the epidemiology or outcomes of critically-ill patients with CLABSIs after implementation of bundle care remain unknown. We aimed to evaluate the incidence, microbiological characteristics, and factors associated with mortality in critically-ill patients after implementation of bundle care.

METHODS

Prospective surveillance was performed on patients admitted to ICUs at the National Taiwan University Hospital, Taipei, Taiwan from January 2012 to June 2013. The demographic, microbiological, and clinical data of patients who developed CLABSI according to the National Healthcare Safety Network definition were reviewed. A total of 181 episodes of CLABSI were assessed in 156 patients over 46,020 central-catheter days.

RESULTS

The incidence of CLABSI was 3.93 per 1000 central-catheter days. The predominant causative microorganisms isolated from CLABSI episodes were Gram-negative bacteria (39.2%), followed by Gram-positive bacteria (33.2%) and Candida spp. (27.6%). Median time from insertion of a central catheter to occurrence of CLABSI was 8 days. In multivariate analysis, the independent factors associated with mortality were higher Pitt bacteremia score [odds ratio (OR) 1.41; 95% confidence interval (CI) 1.18-1.68] and longer interval between onset of CLABSIs and catheter removal (OR 1.10; 95% CI 1.02-1.20), respectively.

CONCLUSION

In institutions with a high proportion of CLABSI caused by Gram-negative bacteria, severity of bacteremia and delay in catheter removal were significant factors associated with mortality.

Antimicrobial resistance in hospital-acquired gram-negative bacterial infections

Aerobic gram-negative bacilli, including the family of Enterobacteriaceae and non-lactose fermenting bacteria such as Pseudomonas and Acinetobacter species, are major causes of hospital-acquired infections. The rate of antibiotic resistance among these pathogens has accelerated dramatically in recent years and has reached pandemic scale. It is no longer uncommon to encounter gram-negative infections that are untreatable using conventional antibiotics in hospitalized patients. In this review, we provide a summary of the major classes of gram-negative bacilli and their key mechanisms of antimicrobial resistance, discuss approaches to the treatment of these difficult infections, and outline methods to slow the further spread of resistance mechanisms.

Nosocomial infection in trauma intensive care

This editorial examines the epidemiology of nosocomial infection in trauma intensive care. Specifically, ventilator-associated pneumonia, central line-associated blood stream infection, and catheter-associated urinary tract infection rates are described. Two important trends are observed. Firstly, nosocomial infection rates have fallen with time. This trend is evident in all intensive care populations and is thought to be principally due to the adoption of preventative bundle strategies. Secondly, rates remain consistently higher in trauma patients than in other intensive care populations. The reasons for this are likely to be multifactorial. Recognizing the particular vulnerability of this patient group should prompt especially rigorous efforts at prevention, early diagnosis, and management.