Mortality and hospital stay associated with resistant Staphylococcus aureus and Escherichia coli bacteremia: estimating the burden of antibiotic resistance in Europe

Characteristics of hospital-acquired and community-onset blood stream infections, South-East Austria

Purpose

The objective of this study was to compare epidemiology, causative pathogens, outcome, and levels of laboratory markers of inflammation of community-onset (i.e. community-acquired and healthcare-associated) and hospital-acquired bloodstream infection (BSI) in South-East Austria.

Methods

In this prospective cohort study, 672 patients fulfilling criteria of systemic inflammatory response syndrome with positive peripheral blood cultures (277 community-onset [192 community-acquired, 85 healthcare-associated BSI], 395 hospital-acquired) were enrolled at the Medical University of Graz, Austria from 2011 throughout 2012. Clinical, microbiological, demographic as well as outcome and laboratory data was collected.

Results

Escherichia coli followed by Staphylococcus aureus were the most frequently isolated pathogens. While Streptococcus spp. and Escherichia coli were isolated more frequently in patients with community-onset BSI, Enterococcus spp., Candida spp., Pseudomonas spp., Enterobacter spp., and coagulase-negative staphylococci were isolated more frequently among those with hospital-acquired BSI. With regard to the outcome, 30-day (82/395 vs. 31/277; p = 0.001) and 90-day mortality (106/395 vs. 35/277; p<0.001) was significantly higher among patients with hospital-acquired BSI even though these patients were significantly younger. Also, hospital-acquired BSI remained a significant predictor of mortality in multivariable analysis. At the time the blood cultures were drawn, patients with community-onset BSI had significantly higher leukocyte counts, neutrophil-leucocyte ratios as well as C-reactive protein, procalcitonin, interleukin-6 and serum creatinine levels when compared to those with hospital-acquired BSI. Patients with healthcare-associated BSI presented with significantly higher PCT and creatinine levels than those with community-acquired BSI.

Conclusions

Hospital-acquired BSI was associated with significantly higher 30- and 90-day mortality rates. Hospital-acquired BSI therefore poses an important target for the most aggressive strategies for prevention and infection control.

Cycling empirical antibiotic therapy in hospitals: meta-analysis and models

The rise of resistance together with the shortage of new broad-spectrum antibiotics underlines the urgency of optimizing the use of available drugs to minimize disease burden. Theoretical studies suggest that coordinating empirical usage of antibiotics in a hospital ward can contain the spread of resistance. However, theoretical and clinical studies came to different conclusions regarding the usefulness of rotating first-line therapy (cycling). Here, we performed a quantitative pathogen-specific meta-analysis of clinical studies comparing cycling to standard practice. We searched PubMed and Google Scholar and identified 46 clinical studies addressing the effect of cycling on nosocomial infections, of which 11 met our selection criteria. We employed a method for multivariate meta-analysis using incidence rates as endpoints and find that cycling reduced the incidence rate/1000 patient days of both total infections by 4.95 [9.43–0.48] and resistant infections by 7.2 [14.00–0.44]. This positive effect was observed in most pathogens despite a large variance between individual species. Our findings remain robust in uni- and multivariate metaregressions. We used theoretical models that reflect various infections and hospital settings to compare cycling to random assignment to different drugs (mixing). We make the realistic assumption that therapy is changed when first line treatment is ineffective, which we call “adjustable cycling/mixing”. In concordance with earlier theoretical studies, we find that in strict regimens, cycling is detrimental. However, in adjustable regimens single resistance is suppressed and cycling is successful in most settings. Both a meta-regression and our theoretical model indicate that “adjustable cycling” is especially useful to suppress emergence of multiple resistance. While our model predicts that cycling periods of one month perform well, we expect that too long cycling periods are detrimental. Our results suggest that “adjustable cycling” suppresses multiple resistance and warrants further investigations that allow comparing various diseases and hospital settings.

The rise of antibiotic resistance is a major concern for public health. In hospitals, frequent usage of antibiotics leads to high resistance levels; at the same time the patients are especially vulnerable. We therefore urgently need treatment strategies that limit resistance without compromising patient care. Here, we investigate two strategies that coordinate the usage of different antibiotics in a hospital ward: “cycling”, i.e. scheduled changes in antibiotic treatment for all patients, and “mixing”, i.e. random assignment of patients to antibiotics. Previously, theoretical and clinical studies came to different conclusions regarding the usefulness of these strategies. We combine meta-analyses of clinical studies and epidemiological modeling to address this question. Our meta-analyses suggest that cycling is beneficial in reducing the total incidence rate of hospital-acquired infections as well as the incidence rate of resistant infections, and that this is most pronounced at low baseline levels of resistance. We corroborate our findings with theoretical epidemiological models. When incorporating treatment adjustment upon deterioration of a patient's condition (“adjustable cycling”), we find that our theoretical model is in excellent accordance with the clinical data. With this combined approach we present substantial evidence that adjustable cycling can be beneficial for suppressing the emergence of multiple resistance.

Horizontal gene transfer in the human gastrointestinal tract: potential spread of antibiotic resistance genes

Bacterial infections are becoming increasingly difficult to treat due to widespread antibiotic resistance among pathogens. This review aims to give an overview of the major horizontal transfer mechanisms and their evolution and then demonstrate the human lower gastrointestinal tract as an environment in which horizontal gene transfer of resistance determinants occurs. Finally, implications for antibiotic usage and the development of resistant infections and persistence of antibiotic resistance genes in populations as a result of horizontal gene transfer in the large intestine will be discussed.

Human health impacts of antibiotic use in agriculture: A push for improved causal inference

Resistant bacterial infections in humans continue to pose a significant challenge globally. Antibiotic use in agriculture contributes to this problem, but failing to appreciate the relative importance of diverse potential causes represents a significant barrier to effective intervention. Standard epidemiologic methods alone are often insufficient to accurately describe the relationships between agricultural antibiotic use and resistance. The integration of diverse methodologies from multiple disciplines will be essential, including causal network modeling and population dynamics approaches. Because intuition can be a poor guide in directing investigative efforts of these non-linear and interconnected systems, integration of modeling efforts with empirical epidemiology and microbiology in an iterative process may result in more valuable information than either in isolation.

Transmissibility of livestock-associated methicillin-resistant Staphylococcus aureus

Previous findings have suggested that the nosocomial transmission capacity of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is lower than that of other MRSA genotypes. We therefore performed a 6-month (June 1–November 30, 2011) nationwide study to quantify the single-admission reproduction number, R_A, for LA-MRSA in 62 hospitals in the Netherlands and to compare this transmission capacity to previous estimates. We used spa typing for genotyping. Quantification of R_A was based on a mathematical model incorporating outbreak sizes, detection rates, and length of hospital stay. There were 141 index cases, 40 (28%) of which were LA-MRSA. Contact screening of 2,101 patients and 7,260 health care workers identified 18 outbreaks (2 LA-MRSA) and 47 secondary cases (3 LA-MRSA). R_A values indicated that transmissibility of LA-MRSA is 4.4 times lower than that of other MRSA (not associated with livestock).

Prevention of meticillin-resistant Staphylococcus aureus bloodstream infections in European hospitals: moving beyond policies

BACKGROUND

There is evidence that meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia can be reduced with improved infection control and antibiotic stewardship.

AIM

To survey infection control and antibiotic stewardship practices within European hospitals and to identify initiatives that correlate with reduced MRSA prevalence.

METHODS

Online questionnaires were sent to European hospitals about their surveillance, hand hygiene, intravenous device management, admission screening, isolation, antibiotic prescribing, hospital demographics and MRSA blood culture isolates during 2010.

FINDINGS

In all, 269 replies were received from hospitals in 29 European countries. Lower MRSA prevalence showed significant association with presence of incidence surveillance, performance of root cause analysis, mandatory training requirements for hand hygiene, accountability measures for persistent non-compliance, and multi-stakeholder teamwork in antibiotic prescribing. Presence of policies on intravenous catheter insertion and management showed no variation between different MRSA prevalence groups. However, low-prevalence hospitals reported more competency assessment programmes in insertion and maintenance of peripheral and central venous catheters. Hospitals from the UK and Ireland reported the highest uptake of infection control and antibiotic stewardship practices that were significantly associated with low MRSA prevalence, whereas Southern European hospitals exhibited the lowest. In multiple regression analysis, isolation of high-risk patients, performance of root cause analysis, obligatory training for nurses in hand hygiene, and undertaking joint ward rounds including microbiologists and infectious disease physicians remained significantly associated with lower MRSA prevalence.

CONCLUSION

Proactive infection control and antibiotic stewardship initiatives that instilled accountability, ownership, teamwork, and validated competence among healthcare workers were associated with improved MRSA outcomes.

Analysis of MRSA-attributed costs of hospitalized patients in Germany

Infections with methicillin-resistant Staphylococcus aureus (MRSA) are assumed to have a high economic impact due to increased hygienic measures and prolonged hospital length of stay. However, surveys on the real expenditure for the prevention and treatment of MRSA are scarce, in particular with regard to the German Diagnosis-Related Groups (G-DRG) payment system. The aim of our study is to empirically assess the additional cost for MRSA management measures and to identify the main cost drivers in the whole process from the hospital's point of view. We conducted a one-year retrospective analysis of MRSA-positive cases in a German university hospital and determined the cost of hygienic measures, laboratory costs, and opportunity costs due to isolation time and extended lengths of stay. A total of 182 cases were included in the analysis. The mean length of hospital stay was 22.75 days and the mean time in isolation was 17.08 days, respectively. Overall, the calculated MRSA-attributable costs were <euro> 8,673.04 per case, with opportunity costs making up, by far, the largest share (77.45 %). Our study provides a detailed up-to-date analysis of MRSA-attributed costs in a hospital. It allows a current comparison to previous studies worldwide. Moreover, it offers the prerequisites to investigate the adequate reimbursement of MRSA burden in the DRG payment system and to assess the efficiency of targeted hygienic measures in the prevention of MRSA.

Prevalence and genotypes of extended spectrum beta-lactamases in Enterobacteriaceae isolated from human stool and chicken meat in Hamburg, Germany

Chicken meat has been proposed to constitute a source for extended spectrum beta-lactamase (ESBL)-carrying Enterobacteriaceae that colonize and infect humans. In this study the prevalence of ESBL-producing Enterobacteriaceae in stool samples from ambulatory patients who presented in the emergency department of the University Medical Centre Hamburg-Eppendorf with gastrointestinal complains and in chicken meat samples from the Hamburg region were analysed and compared with respect to ESBL-genotypes, sequence types and antibiotic resistance profiles. Twenty-nine (4.1%) of 707 stool samples and 72 (60%) of 120 chicken meat samples were positive for ESBL-producing Enterobacteriaceae. The distribution of ESBL genes in the stool vs. chicken meat isolates (given as % of total isolates from stool vs. chicken meat) was as follows: CTX-M-15 (38% vs. 0%), CTX-M-14 (17% vs. 6%), CTX-M-1 (17% vs. 69%), SHV-12 (3% vs. 18%) and TEM-52 (3% each). Comparison of ESBL- and multilocus sequence type revealed no correlation between isolates of human and chicken. Furthermore, ESBL-producing E. coli from stool samples were significantly more resistant to fluoroquinolones, aminoglycosides and/or trimethoprim-sulfamethoxazole than chicken isolates. The differences in ESBL-genotypes, sequence types and antibiotic resistance patterns indicate that in our clinical setting chicken meat is not a major contributor to human colonization with ESBL-carrying Enterobacteriaceae.

Antibiotic consumption and antibiotic stewardship in Swedish hospitals

BACKGROUND

The aim of this paper was to describe and analyze the effect of antibiotic policy changes on antibiotic consumption in Swedish hospitals and to review antibiotic stewardship in Swedish hospitals.

RESULTS

The main findings were: 1) Antibiotic consumption has significantly increased in Swedish hospitals over the last decade. The consumption of cephalosporins has decreased, whereas that of most other drugs including piperacillin-tazobactam, carbapenems, and penicillinase-sensitive and -resistant penicillins has increased and replaced cephalosporins. 2) Invasive infections caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae have increased, but the proportion of pathogens resistant to third-generation cephalosporins causing invasive infections is still very low in a European and international perspective. Furthermore, the following gaps in knowledge were identified: 1) lack of national, regional, and local data on the incidence of antibiotic resistance among bacteria causing hospital-acquired infections e.g. bloodstream infections and hospital-acquired pneumonia-data on which standard treatment guidelines should be based; 2) lack of data on the incidence of Clostridium difficile infections and the effect of change of antibiotic policies on the incidence of C. difficile infections and infections caused by antibiotic-resistant pathogens; and 3) lack of prospective surveillance programs regarding appropriate antibiotic treatment, including selection of optimal antimicrobial drug regimens, dosage, duration of therapy, and adverse ecological effects such as increases in C. difficile infections and emergence of antibiotic-resistant pathogens.

CONCLUSIONS

Evidence-based actions to improve antibiotic use and to slow down the problem of antibiotic resistance need to be strengthened. The effect of such actions should be analyzed, and standard treatment guidelines should be continuously updated at national, regional, and local levels.

A review article on the benefits of early mobilization following spinal surgery and other medical/surgical procedures

Background:

The impact of early mobilization on perioperative comorbidities and length of stay (LOS) has shown benefits in other medical/surgical subspecialties. However, few spinal series have specifically focused on the “pros” of early mobilization for spinal surgery, other than in acute spinal cord injury. Here we reviewed how early mobilization and other adjunctive measures reduced morbidity and LOS in both medical and/or surgical series, and focused on how their treatment strategies could be applied to spinal patients.

Methods:

We reviewed studies citing protocols for early mobilization of hospitalized patients (day of surgery, first postoperative day/other) in various subspecialties, and correlated these with patients’ perioperative morbidity and LOS. As anticipated, multiple comorbid factors (e.g. hypertension, high cholesterol, diabetes, hypothyroidism, obesity/elevated body mass index hypothyroidism, osteoporosis, chronic obstructive pulmonary disease, coronary artery disease and other factors) contribute to the risks and complications of immobilization for any medical/surgical patient, including those undergoing spinal procedures. Some studies additionally offered useful suggestions specific for spinal patients, including prehabilitation (e.g. rehabilitation that starts prior to surgery), preoperative and postoperative high protein supplements/drinks, better preoperative pain control, and early tracheostomy, while others cited more generalized recommendations.

Results:

In many studies, early mobilization protocols reduced the rate of complications/morbidity (e.g. respiratory decompensation/pneumonias, deep venous thrombosis/pulmonary embolism, urinary tract infections, sepsis or infection), along with the average LOS.

Conclusions:

A review of multiple medical/surgical protocols promoting early mobilization of hospitalized patients including those undergoing spinal surgery reduced morbidity and LOS.

High-throughput screening of metal-N-heterocyclic carbene complexes against biofilm formation by pathogenic bacteria

A set of molecules including a majority of metal-N-heterocyclic carbene (NHC) complexes (metal=Ag, Cu, and Au) and azolium salts were evaluated by high-throughput screening of their activity against biofilm formation associated with pathogenic bacteria. The anti-planktonic effects were compared in parallel. Representative biofilm-forming strains of various genera were selected (Listeria, Pseudomonas, Staphylococcus, and Escherichia). All the compounds were tested at 1 mg L(-1) by using the BioFilm Ring Test. An information score (IS, sum of the activities) and an activity score (AS, difference between anti-biofilm and anti-planktonic activity) were determined from normalized experimental values to classify the most active molecules against the panel of bacterial strains. With this method we identified lipophilic Ag(I) and Cu(I) complexes possessing aromatic groups on the NHC ligand as the most efficient at inhibiting biofilm formation.

Evaluation of a pulsed-xenon ultraviolet room disinfection device for impact on contamination levels of methicillin-resistant Staphylococcus aureus

BACKGROUND

Healthcare-acquired infections with methicillin-resistant Staphylococcus aureus (MRSA) are a significant cause of increased mortality, morbidity and additional health care costs in United States. Surface decontamination technologies that utilize pulsed xenon ultraviolet light (PPX-UV) may be effective at reducing microbial burden. The purpose of this study was to compare standard manual room-cleaning to PPX-UV disinfection technology for MRSA and bacterial heterotrophic plate counts (HPC) on high-touch surfaces in patient rooms.

METHODS

Rooms vacated by patients that had a MRSA-positive polymerase chain reaction or culture during the current hospitalization and at least a 2-day stay were studied. 20 rooms were then treated according to one of two protocols: standard manual cleaning or PPX-UV. This study evaluated the reduction of MRSA and HPC taken from five high-touch surfaces in rooms vacated by MRSA-positive patients, as a function of cleaning by standard manual methods vs a PPX-UV area disinfection device.

RESULTS

Colony counts in 20 rooms (10 per arm) prior to cleaning varied by cleaning protocol: for HPC, manual (mean = 255, median = 278, q1-q3 132-304) vs PPX-UV (mean = 449, median = 365, q1-q3 332-530), and for MRSA, manual (mean = 127; median = 28.5; q1-q3 8-143) vs PPX-UV (mean = 108; median = 123; q1-q3 14-183). PPX-UV was superior to manual cleaning for MRSA (adjusted incident rate ratio [IRR] = 7; 95% CI <1-41) and for HPC (IRR = 13; 95% CI 4-48).

CONCLUSION

PPX-UV technology appears to be superior to manual cleaning alone for MRSA and HPC. Incorporating 15 minutes of PPX-UV exposure time to current hospital room cleaning practice can improve the overall cleanliness of patient rooms with respect to selected micro-organisms.

Nonculture techniques for the detection of bacteremia and fungemia

ABSTRACT: 

Bacteremia and fungemia account for a substantial proportion of all cases of severe sepsis. Antibiotic resistance is a contributing factor in many hospital-acquired infection deaths. Traditional phenotypic methods for the identification of bacteria and yeasts from positive blood cultures and determining antimicrobial susceptibility require 48–72 h, delaying optimal therapy and negatively impacting patient outcomes. Molecular methods, including nonamplified DNA probe panels and peptide nucleic acid probes, and nucleic acid amplification methods such as PCR, proteomic methods (matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry) and direct biochemical tests provide more rapid identification of bacteria and fungi, and in some cases antimicrobial resistance markers, from positive blood cultures, as well as directly from whole blood. These methods vary in the breadth of organisms that they detect, and equally important, their ease of use. This article examines the principles, performance and practicality of the various rapid, nonculture techniques for the detection of bacteremia and fungemia.

Characterization of third-generation cephalosporin-resistant Escherichia coli from bloodstream infections in Denmark

The aim of the study was to investigate the molecular epidemiology of 87 third-generation cephalosporin-resistant Escherichia coli (3GC-R Ec) from bloodstream infections in Denmark from 2009. Sixty-eight of the 87 isolates were extended-spectrum beta-lactamase (ESBL) producers, whereas 17 isolates featured AmpC mutations only (without a coexpressed ESBL enzyme) and 2 isolates were producing CMY-22. The majority (82%) of the ESBL-producing isolates in our study were CTX-M-15 producers and primarily belonged to phylogroup B2 (54.4%) or D (23.5%). Further, one of the two CMY-22-producing isolates belonged to B2, whereas only few of the other AmpCs isolates belonged to B2 and D. Pulsed-field gel electrophoresis revealed that both clonal and nonclonal spread of 3GC-R Ec occurred. ST131 was detected in 50% of ESBL-producing isolates. The remaining ESBL-producing isolates belonged to 17 other sequence types (STs), including several other internationally spreading STs (e.g., ST10, ST69, and ST405). The majority (93%) of the ESBL-producing isolates and one of the CMY-22-producing isolates were multiresistant. In conclusion, 3GC-R in bacteriaemic E. coli in Denmark was mostly due to ESBL production, overexpression of AmpC, and to a lesser extent to plasmid-mediated AmpC. The worldwide disseminated CTX-M-15-ST131 was strongly represented in this collection of Danish, bacteriaemic E. coli isolates.

Exposure assessment of extended-spectrum beta-lactamases/AmpC beta-lactamases-producing Escherichia coli in meat in Denmark

Introduction

Extended-spectrum beta-lactamases (ESBL) and AmpC beta-lactamases (AmpC) are of concern for veterinary and public health because of their ability to cause treatment failure due to antimicrobial resistance in Enterobacteriaceae. The main objective was to assess the relative contribution (RC) of different types of meat to the exposure of consumers to ESBL/AmpC and their potential importance for human infections in Denmark.

Material and methods

The prevalence of each genotype of ESBL/AmpC-producing E. coli in imported and nationally produced broiler meat, pork and beef was weighted by the meat consumption patterns. Data originated from the Danish surveillance program for antibiotic use and antibiotic resistance (DANMAP) from 2009 to 2011. DANMAP also provided data about human ESBL/AmpC cases in 2011, which were used to assess a possible genotype overlap. Uncertainty about the occurrence of ESBL/AmpC-producing E. coli in meat was assessed by inspecting beta distributions given the available data of the genotypes in each type of meat.

Results and discussion

Broiler meat represented the largest part (83.8%) of the estimated ESBL/AmpC-contaminated pool of meat compared to pork (12.5%) and beef (3.7%). CMY-2 was the genotype with the highest RC to human exposure (58.3%). However, this genotype is rarely found in human infections in Denmark.

Conclusion

The overlap between ESBL/AmpC genotypes in meat and human E. coli infections was limited. This suggests that meat might constitute a less important source of ESBL/AmpC exposure to humans in Denmark than previously thought – maybe because the use of cephalosporins is restricted in cattle and banned in poultry and pigs. Nonetheless, more detailed surveillance data are required to determine the contribution of meat compared to other sources, such as travelling, pets, water resources, community and hospitals in the pursuit of a full source attribution model.

Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran

Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

Epidemiology of extended-spectrum β-lactamase-producing Escherichia coli in Sweden 2007-2011

Extended-spectrum β-lactamase (ESBL) -producing Enterobacteriaceae have been notifiable according to the Swedish Communicable Disease Act since 2007. A major increase in the number of cases has been observed, with 2099 cases in 2007 and 7225 cases in 2012. The majority of the isolates are Escherichia coli. Additionally, Swedish data on the prevalence of ESBL-producing invasive isolates of E. coli are available through EARS-Net, and through biannual point prevalence studies, where molecular characterization of isolates from the entire country is carried out. This paper describes major trends in the Swedish epidemiology of ESBL-producing E. coli in the period 2007-2012. Isolates from the point prevalence studies were subjected to antimicrobial susceptibility testing, ESBL genotyping, pulsed-field gel electrophoresis, multi-locus sequence typing and phylogenetic grouping with PCR. The distribution of sequence types, resistance genes and susceptibility levels were all stable over the three study periods. The dominating resistance gene conferring ESBL was blaCTX -M-15 , found in 54-58% of the isolates. ST131 represented 34-38% of the isolates. Other major sequence types were ST38, ST69, ST405, ST617 and ST648, each representing 2-6% of the isolates. Phylogenetic group B2 was the most common, and was observed in 41-47% of the isolates. However, among ST131 isolates the B2 phylogenetic group represented 90-98% of the isolates. The most important epidemiological difference seen over time was that the median age of infected women decreased from 62 to 52 years (p <0.0001) and infected men from 67 to 64 years. A potential explanation might be the shift towards a higher proportion of community-acquired infections in individuals lacking comorbidities.

Antibiotic resistance-the need for global solutions

The causes of antibiotic resistance are complex and include human behaviour at many levels of society; the consequences affect everybody in the world. Similarities with climate change are evident. Many efforts have been made to describe the many different facets of antibiotic resistance and the interventions needed to meet the challenge. However, coordinated action is largely absent, especially at the political level, both nationally and internationally. Antibiotics paved the way for unprecedented medical and societal developments, and are today indispensible in all health systems. Achievements in modern medicine, such as major surgery, organ transplantation, treatment of preterm babies, and cancer chemotherapy, which we today take for granted, would not be possible without access to effective treatment for bacterial infections. Within just a few years, we might be faced with dire setbacks, medically, socially, and economically, unless real and unprecedented global coordinated actions are immediately taken. Here, we describe the global situation of antibiotic resistance, its major causes and consequences, and identify key areas in which action is urgently needed.

Staphylococcus aureus bloodstream infection: a pooled analysis of five prospective, observational studies

OBJECTIVES

Staphylococcus aureus bacteraemia is a common, often fatal infection. Our aim was to describe how its clinical presentation varies between populations and to identify common determinants of outcome.

METHODS

We conducted a pooled analysis on 3395 consecutive adult patients with S. aureus bacteraemia. Patients were enrolled between 2006 and 2011 in five prospective studies in 20 tertiary care centres in Germany, Spain, United Kingdom, and United States.

RESULTS

The median age of participants was 64 years (interquartile range 50-75 years) and 63.8% were male. 25.4% of infections were associated with diabetes mellitus, 40.7% were nosocomial, 20.6% were caused by methicillin-resistant S. aureus (MRSA), although these proportions varied significantly across studies. Intravenous catheters were the commonest identified infective focus (27.7%); 8.3% had endocarditis. Crude 14 and 90-day mortality was 14.6% and 29.2%, respectively. Age, MRSA bacteraemia, nosocomial acquisition, endocarditis, and pneumonia were independently associated with death, but a strong association was with an unidentified infective focus (adjusted hazard ratio for 90-day mortality 2.92; 95% confidence interval 2.33 to 3.67, p < 0.0001).

CONCLUSION

The baseline demographic and clinical features of S. aureus bacteraemia vary significantly between populations. Mortality could be reduced by assiduous MRSA control and early identification of the infective focus.

Withdrawal of Staphylococcus aureus from intensive care units in Turkey

BACKGROUND

In the past, Staphylococcus aureus infections have displayed various patterns of epidemiologic curves in hospitals, particularly in intensive care units (ICUs). This study aimed to characterize the current trend in a nationwide survey of ICUs in Turkey.

METHODS

A total of 88 ICUs from 36 Turkish tertiary hospitals were included in this retrospective study, which was performed during the first 3 months of both 2008 (period [P] 1) and 2011 (P2). A P value ≤.01 was considered significant.

RESULTS

Although overall rates of hospital-acquired infection (HAI) and device-associated infection densities were similar in P1 and P2, the densities of HAIs due to S aureus and methicillin-resistant S aureus (MRSA) were significantly lower in P2 (P < .0001). However, the proportion of HAIs due to Acinetobacter was significantly higher in P2 (P < .0001).

CONCLUSIONS

The incidence of S aureus infections is declining rapidly in Turkish ICUs, with potential impacts on empirical treatment strategies in these ICUs.

A survey of resident physicians' knowledge regarding urine testing and subsequent antimicrobial treatment

BACKGROUND

Asymptomatic bacteriuria is often treated with antimicrobials despite no benefit to patients, contributing to antimicrobial resistance and costs. Identifying knowledge deficits may improve physician training and antimicrobial stewardship efforts. We surveyed internal medicine and medicine-pediatrics resident physicians about their knowledge and attitudes regarding urine testing and subsequent management.

METHODS

We surveyed 280 resident physicians at Jackson Memorial Hospital/University of Miami Miller School of Medicine and the University of Minnesota Medical School, using patient management questions based on clinical vignettes. Overall knowledge, assessed by calculating the percentage of correct answers, was assessed for correlation with demographic information, training, and experience.

RESULTS

Of 100 responses (36% response rate), the mean percentage of correct answers was 48% (range for individual questions, 19%-85%). Experience and demographic factors demonstrated no association with overall knowledge. Training appeared to be associated with overall knowledge, with third-year residents having significantly higher percentages of correct answers compared with first-year residents (53% vs 40%; P = .03), but this was nonsignificant when adjusted for multiple comparisons (P = .18). Knowledge was significantly better for questions regarding surgical versus nonsurgical scenarios (63% vs 37%; P < .001), and for questions for which the correct answer was to start antimicrobials, versus withholding antimicrobials/limiting further testing (83% vs 39%; P < .001).

CONCLUSIONS

Knowledge deficits may contribute to unnecessary detection and treatment of asymptomatic bacteriuria.

Feasibility and effectiveness of a low cost campaign on antibiotic prescribing in Italy: community level, controlled, non-randomised trial

OBJECTIVES

To test the hypothesis that a multifaceted, local public campaign could be feasible and influence antibiotic prescribing for outpatients.

DESIGN

Community level, controlled, non-randomised trial.

SETTING

Provinces of Modena and Parma in Emilia-Romagna, northern Italy, November 2011 to February 2012.

POPULATION

1,150,000 residents of Modena and Parma (intervention group) and 3,250,000 residents in provinces in the same region but where no campaign had been implemented (control group).

INTERVENTIONS

Campaign materials (mainly posters, brochures, and advertisements on local media, plus a newsletter on local antibiotic resistance targeted at doctors and pharmacists). General practitioners and paediatricians in the intervention area participated in designing the campaign messages.

MAIN OUTCOMES MEASURES

Primary outcome was the average change in prescribing rates of antibiotics for outpatient in five months, measured as defined daily doses per 1000 inhabitants/day, using health districts as the unit of analysis.

RESULTS

Antibiotic prescribing was reduced in the intervention area compared with control area (-4.3%, 95% confidence interval -7.1% to -1.5%). This result was robust to "sensitivity analysis" modifying the baseline period from two months (main analysis) to one month. A higher decrease was observed for penicillins resistant to β lactamase and a lower decrease for penicillins susceptible to β lactamase, consistent with the content of the newsletter on antibiotic resistance directed at health professionals. The decrease in expenditure on antibiotics was not statistically significant in a district level analysis with a two month baseline period (main analysis), but was statistically significant in sensitivity analyses using either a one month baseline period or a more powered doctor level analysis. Knowledge and attitudes of the target population about the correct use of antibiotics did not differ between the intervention and control areas.

CONCLUSIONS

A local low cost information campaign targeted at citizens, combined with a newsletter on local antibiotic resistance targeted at doctors and pharmacists, was associated with significantly decreased total rates of antibiotic prescribing but did not affect the population's knowledge and attitudes about antibiotic resistance.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01604096.

On the use of capillary cytometry for assessing the bactericidal effect of TiO2. Identification and involvement of reactive oxygen species

The photocatalytic antimicrobial properties of TiO2 were studied on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa bacterial strains taken as model strains for pathogenic species mainly implied in nosocomial infections. Capillary cytometry, coupled to a double-staining method for visualizing membrane integrity as a cell viability indicator, was highlighted as a rapid, easy-to-use, and automated numeration technique for quantitative and reproducible determination of cellular viability and thus, was able to give an accurate evaluation of the bactericidal effect of UV-A photocatalysis. Cytometry also enabled the study of TiO2-bacteria interactions and aggregation in the dark as well as TiO2 cytotoxicity. Compared with the traditional agar plate cultivation method, a significatively weaker reduction in cell viability was recorded by cytometry whatever the bacteria, TiO2 concentration, and duration of the photocatalytic treatment. The mismatch between both numeration methods was attributed to: (i) the presence of mixed bacteria-TiO2 aggregates that could interfere with bacteria measurement on plates, (ii) prolonged contact of the bacteria with TiO2 during incubation, which could cause additional cytotoxic damage to the bacterial wall, and (iii) the counting of viable but non-culturable bacteria as live bacteria in cytometry, whereas they cannot grow on solid media. A more pronounced difference was observed for P. aeruginosa and S. aureus bacteria, for which 2.9 and 1.9 log10 survival reduction overestimations were measured by plate counting, respectively. Using chemiluminescence, full restoration of cell viability by controlled addition of the O2˙(-) scavenger superoxide dismutase enzyme suggests that O2˙(-) acts, in our conditions, as the main reactive oxygen species responsible for the photocatalytic attack towards the targeted bacteria.

Utility of prior screening for methicillin-resistant Staphylococcus aureus in predicting resistance of S. aureus infections

BACKGROUND

Screening for methicillin-resistant Staphylococcus aureus (MRSA) is intended to reduce nosocomial spread by identifying patients colonized by MRSA. Given the widespread use of this screening, we evaluated its potential clinical utility in predicting the resistance of clinical isolates of S. aureus.

METHODS

We conducted a 2-year retrospective cohort study that included patients with documented clinical infection with S. aureus and prior screening for MRSA. We determined test characteristics, including sensitivity and specificity, of screening for predicting the resistance of subsequent S. aureus isolates.

RESULTS

Of 510 patients included in the study, 53 (10%) had positive results from MRSA screening, and 79 (15%) of infecting isolates were resistant to methicillin. Screening for MRSA predicted methicillin resistance of the infecting isolate with 99% (95% confidence interval [CI] 98%-100%) specificity and 63% (95% CI 52%-74%) sensitivity. When screening swabs were obtained within 48 hours before isolate collection, sensitivity increased to 91% (95% CI 71%-99%) and specificity was 100% (95% CI 97%-100%), yielding a negative likelihood ratio of 0.09 (95% CI 0.01-0.3) and a negative predictive value of 98% (95% CI 95%-100%). The time between swab and isolate collection was a significant predictor of concordance of methicillin resistance in swabs and isolates (odds ratio 6.6, 95% CI 1.6-28.2).

INTERPRETATION

A positive result from MRSA screening predicted methicillin resistance in a culture-positive clinical infection with S. aureus. Negative results on MRSA screening were most useful for excluding methicillin resistance of a subsequent infection with S. aureus when the screening swab was obtained within 48 hours before collection of the clinical isolate.

Reduction of the nosocomial meticillin-resistant Staphylococcus aureus incidence density by a region-wide search and follow-strategy in forty German hospitals of the EUREGIO, 2009 to 2011

Meticillin-resistant Staphylococcus aureus (MRSA) disseminates between hospitals serving one patient catchment area. Successful prevention and control requires concerted efforts and regional surveillance. Forty hospitals located in the German EUREGIO have established a network for combating MRSA. In 2007 they agreed upon a synchronised strategy for screening of risk patients and a standard for transmissionbased precautions (search and follow). The same year, the hospitals started synchronised MRSA prevention and annually reporting MRSA-data to the public health authorities. The median rate of screening cultures per 100 patients admitted increased from 4.38 in 2007 to 34.4 in 2011 (p<0.0001). Between 2007 and 2011, the overall incidence density of MRSA (0.87 MRSA cases/1,000 patient days vs 1.54; p<0.0001) increased significantly. In contrast, both the incidence density of nosocomial MRSA cases (0.13 nosocomial MRSA cases/1,000 patient days in 2009 vs 0.08 in 2011; p=0.0084) and the MRSA-days-associated nosocomial MRSA rate (5.51 nosocomial MRSA cases/1,000 MRSA days in 2009 vs 3.80 in 2011; p=0.0437) decreased significantly after the second year of the project. We documented adherence to the regional screening strategy resulting in improved detection of MRSA carriers at admission. Subsequently, after two years the nosocomial MRSA-incidence density was reduced. Regional surveillance data, annually provided as benchmarking to the regional hospitals and public health authorities, indicated successful prevention.

Human Health Risk Assessment (HHRA) for environmental development and transfer of antibiotic resistance

BACKGROUND

Only recently has the environment been clearly implicated in the risk of antibiotic resistance to clinical outcome, but to date there have been few documented approaches to formally assess these risks.

OBJECTIVE

We examined possible approaches and sought to identify research needs to enable human health risk assessments (HHRA) that focus on the role of the environment in the failure of antibiotic treatment caused by antibiotic-resistant pathogens.

METHODS

The authors participated in a workshop held 4-8 March 2012 in Québec, Canada, to define the scope and objectives of an environmental assessment of antibiotic-resistance risks to human health. We focused on key elements of environmental-resistance-development "hot spots," exposure assessment (unrelated to food), and dose response to characterize risks that may improve antibiotic-resistance management options.

DISCUSSION

Various novel aspects to traditional risk assessments were identified to enable an assessment of environmental antibiotic resistance. These include a) accounting for an added selective pressure on the environmental resistome that, over time, allows for development of antibiotic-resistant bacteria (ARB); b) identifying and describing rates of horizontal gene transfer (HGT) in the relevant environmental "hot spot" compartments; and c) modifying traditional dose-response approaches to address doses of ARB for various health outcomes and pathways.

CONCLUSIONS

We propose that environmental aspects of antibiotic-resistance development be included in the processes of any HHRA addressing ARB. Because of limited available data, a multicriteria decision analysis approach would be a useful way to undertake an HHRA of environmental antibiotic resistance that informs risk managers.

Human and avian extraintestinal pathogenic Escherichia coli: infections, zoonotic risks, and antibiotic resistance trends

Extraintestinal pathogenic Escherichia coli (ExPEC) constitutes ongoing health concerns for women, newborns, elderly, and immunocompromised individuals due to increased numbers of urinary tract infections (UTIs), newborn meningitis, abdominal sepsis, and septicemia. E. coli remains the leading cause of UTIs, with recent investigations reporting the emergence of E. coli as the predominant cause of nosocomial and neonatal sepsis infections. This shift from the traditional Gram-positive bacterial causes of nosocomial and neonatal sepsis infections could be attributed to the use of intrapartum chemoprophylaxis against Gram-positive bacteria and the appearance of antibiotic (ATB) resistance in E. coli. While ExPEC strains cause significant healthcare concerns, these bacteria also infect chickens and cause the poultry industry economic losses due to costs of containment, mortality, and disposal of carcasses. To circumvent ExPEC-related costs, ATBs are commonly used in the poultry industry to prevent/treat microbial infections and promote growth and performance. In an unfortunate linkage, chicken products are suspected to be a source of foodborne ExPEC infections and ATB resistance in humans. Therefore, the emergence of multidrug resistance (MDR) (resistance to three or more classes of antimicrobial agents) among avian E. coli has created major economic and health concerns, affecting both human healthcare and poultry industries. Increased numbers of immunocompromised individuals, including the elderly, coupled with MDR among ExPEC strains, will continue to challenge the treatment of ExPEC infections and likely lead to increased treatment costs. With ongoing complications due to emerging ATB resistance, novel treatment strategies are necessary to control ExPEC infections. Recognizing and treating the zoonotic risk posed by ExPEC would greatly enhance food safety and positively impact human health.

Targeted versus universal screening and decolonization to reduce healthcare-associated meticillin-resistant Staphylococcus aureus infection

BACKGROUND

The benefits of universal meticillin-resistant Staphylococcus aureus (MRSA) admission screening, compared with screening targeted patient groups and the additional impact of discharge screening, are uncertain.

AIMS

To quantify the impact of MRSA screening plus decolonization treatment on MRSA infection rates. To compare universal with targeted screening policies, and to evaluate the additional impact of screening and decolonization on discharge.

METHODS

A stochastic, individual-based model of MRSA transmission was developed that included patient movements between general medical and intensive care unit (ICU) wards, and between the hospital and community, informed by 18 months of individual patient data from a 900-bed tertiary care hospital. We simulated the impact of universal and targeted [for ICU, acute care of the elderly (ACE) or readmitted patients] MRSA screening and decolonization policies, both on admission and discharge.

FINDINGS

Universal admission screening plus decolonization resulted in 77% (95% confidence interval: 76-78) reduction in MRSA infections over 10 years. Screening only ACE specialty or ICU patients yielded 62% (61-63) and 66% (65-67) reductions, respectively. Targeted policies reduced the number of screens by up to 95% and courses of decolonization by 96%. In addition to screening on admission, screening on discharge had little impact, with a maximum 7% additional reduction in infection.

CONCLUSIONS

Compared with universal screening, targeted screening substantially reduced the amount of screening and decolonization required to achieve only 12% lower reduction in infection. Targeted screening and decolonization could lower the risk of resistance emerging as well as offer a more efficient use of resources.

Hospital cross-transmission of extended-spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae

OBJECTIVES

We had for objective to measure the incidence and the clonal diversity of Escherichia coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases (ESBL) in order to assess the role of patient stay in amplification of the phenomenon, in our teaching hospital.

MATERIAL AND METHODS

We measured the quarterly incidence rates of E. coli and K. pneumoniae producing or not producing ESBL in clinical samples between 1999 and 2010. The incidence of ESBL-producing isolates was season-adjusted. We determined the pulsotype of and identified the ESBL in all non-redundant strains isolated between 2009 and 2010.

RESULTS

The incidence for 1000 hospitalization days increased from 0.00 to 0.44 for ESBL-producing E. coli, from 0.012 to 0.24 for ESBL-producing K. pneumoniae, from 1999 to 2010. Fifty-three different clones of E. coli were identified among the 61 genotyped isolates. The 28 K. pneumoniae isolates genotyped clustered into 11 different clones, among which one major epidemic clone that included 18 isolates. Respectively 66 and 75% of E. coli and K. pneumoniae isolates produced a CTX-M group 1 ESBL.

CONCLUSION

The hospital seems to play a different role in the amplification of ESBL according to the producing species (K. pneumoniae or E. coli). ESBL-producing E. coli seem to have a limited cross-transmission within the hospital and seem to be added to non-producers. Conversely, ESBL-producing K. pneumoniae seem to be cross-transmitted within the hospital and to replace non-producers.

Predictors and molecular epidemiology of community-onset extended-spectrum β-lactamase-producing Escherichia coli infection in a Midwestern community

OBJECTIVE

To identify predictors of community-onset extended-spectrum β-lactamase (ESBL)-producing Escherichia coli infection.

DESIGN

Prospective case-control study.

SETTING

Acute care hospitals and ambulatory clinics in the Chicago, Illinois, region.

PATIENTS

Adults with E. coli clinical isolates cultured in ambulatory settings or within 48 hours of hospital admission.

METHODS

Cases were patients with ESBL-producing E. coli clinical isolates cultured in ambulatory settings or within 48 hours of admission, and controls were patients with non-ESBL-producing E. coli isolates, matched to cases by specimen, location, and date. Clinical variables were ascertained through interviews and medical record review. Molecular methods were used to identify ESBL types, sequence type ST131, and aac(6')-Ib-cr.

RESULTS

We enrolled 94 cases and 158 controls. Multivariate risk factors for ESBL-producing E. coli infection included travel to India in the past year (odds ratio [OR], 14.40 [95% confidence interval (CI), 2.92-70.95]), ciprofloxacin use (OR, 3.92 [95% CI, 1.90-8.1]), and age (OR, 1.04 [95% CI, 1.02-1.06]). Case isolates exhibited high prevalence of CTX-M-15 (78%), ST131 (50%), and aac(6')-Ib-cr (66% of isolates with CTX-M-15).

CONCLUSIONS

Providers should be aware of the increased risk of ESBL-producing E. coli infection among returned travelers, especially those from India.

Modelling the transmission of healthcare associated infections: a systematic review

Background

Dynamic transmission models are increasingly being used to improve our understanding of the epidemiology of healthcare-associated infections (HCAI). However, there has been no recent comprehensive review of this emerging field. This paper summarises how mathematical models have informed the field of HCAI and how methods have developed over time.

Methods

MEDLINE, EMBASE, Scopus, CINAHL plus and Global Health databases were systematically searched for dynamic mathematical models of HCAI transmission and/or the dynamics of antimicrobial resistance in healthcare settings.

Results

In total, 96 papers met the eligibility criteria. The main research themes considered were evaluation of infection control effectiveness (64%), variability in transmission routes (7%), the impact of movement patterns between healthcare institutes (5%), the development of antimicrobial resistance (3%), and strain competitiveness or co-colonisation with different strains (3%). Methicillin-resistant Staphylococcus aureus was the most commonly modelled HCAI (34%), followed by vancomycin resistant enterococci (16%). Other common HCAIs, e.g. Clostridum difficile, were rarely investigated (3%). Very few models have been published on HCAI from low or middle-income countries.

The first HCAI model has looked at antimicrobial resistance in hospital settings using compartmental deterministic approaches. Stochastic models (which include the role of chance in the transmission process) are becoming increasingly common. Model calibration (inference of unknown parameters by fitting models to data) and sensitivity analysis are comparatively uncommon, occurring in 35% and 36% of studies respectively, but their application is increasing. Only 5% of models compared their predictions to external data.

Conclusions

Transmission models have been used to understand complex systems and to predict the impact of control policies. Methods have generally improved, with an increased use of stochastic models, and more advanced methods for formal model fitting and sensitivity analyses. Insights gained from these models could be broadened to a wider range of pathogens and settings. Improvements in the availability of data and statistical methods could enhance the predictive ability of models.

Will there ever be a universal Staphylococcus aureus vaccine?

Developing a universal vaccine for S. aureus is a top priority but to date we have only had failures in human clinical trials. Given the plethora of bacterial virulence factors, broad range of the health of humans at-risk for infections, lack of any information regarding immune effectors mediating protection for any manifestation of S. aureus infection and overall competence of this organism as a colonizer, commensal and pathogen, we may just simply have to accept the fact that we will not get a universal vaccine. Antigenic variation is a major challenge for some vaccine targets and for many conserved targets the organism can easily decrease or even eliminate expression to avoid immune effectors without compromise to infectivity and ability to cause disease. Studies of human immune responses similarly have been unable to identify any clear mediators of immunity and data from such studies can only eliminate those found not to be associated with protection or that might serve as a marker for individuals with a higher level of resistance to infection. Animal studies are not predictive of success in humans and unlikely will be except in hindsight if and when we develop an efficacious vaccine. Successful vaccines for other bacteria based on capsular polysaccharides have not worked to date for S. aureus, and laboratory studies combining antibody to the major capsular serotypes and the other S. aureus surface polysaccharide, poly-N-acetyl glucosamine, unexpectedly showed interference not augmentation of immunity. Potential pathways toward vaccine development do exist but for the foreseeable future will be based on empiric approaches derived from laboratory-based in vitro and animal tests and not on inducing a known immune effector that predicts human resistance to infection.

The scourge of antibiotic resistance: the important role of the environment

Antibiotic resistance and associated genes are ubiquitous and ancient, with most genes that encode resistance in human pathogens having originated in bacteria from the natural environment (eg, β-lactamases and fluoroquinolones resistance genes, such as qnr). The rapid evolution and spread of "new" antibiotic resistance genes has been enhanced by modern human activity and its influence on the environmental resistome. This highlights the importance of including the role of the environmental vectors, such as bacterial genetic diversity within soil and water, in resistance risk management. We need to take more steps to decrease the spread of resistance genes in environmental bacteria into human pathogens, to decrease the spread of resistant bacteria to people and animals via foodstuffs, wastes and water, and to minimize the levels of antibiotics and antibiotic-resistant bacteria introduced into the environment. Reducing this risk must include improved management of waste containing antibiotic residues and antibiotic-resistant microorganisms.

Inpatient treatment of community-acquired pneumonias with integrative medicine

Introduction. The aim of the presented observational case series was to evaluate the experience in treating patients with community-acquired pneumonia (CAP) within integrative medicine, particularly anthroposophic medicine in a well-experienced and specialized unit. Patients and Methods. Patients with proven CAP were evaluated (CAP-study group) based on a retrospective chart review. To estimate the severity of pneumonia, the pneumonia severity index (PSI) was applied. Treatment efficacy was evaluated regarding body temperature, CRP level, leukocytes blood count, the need to be treated on ICU, and mortality. Results were compared with the inpatient data of the Pneumonia PORT Validation Cohort. Results. 15/18 patients of the CAP-study group belonged to risk class groups I–III (low and moderate risk), 2 patients to risk class IV, and one patient to risk class V (severe pneumonia). 16/18 patients were treated with anthroposophic medicine only and 2/18 got additionally antibiotic therapy (both of risk class IV). A significant reduction of body temperature, CRP level, and leukocytes blood count has been obtained by applying anthroposophic medicine, while neither complications nor pneumonia-related death occurred. Compared with the control group there was no significant difference in mortality rate, whereby no patient had to be treated on the ICU, but the duration of hospital stay was significantly longer in the presented series. Conclusion. Inpatient treatment of CAP with anthroposophic medicine without the use of antibiotics may achieve reasonable results in selected cases. Additional larger sized prospective controlled trials should further clarify the role of AM in the treatment of CAP.

Prevention of methicillin-resistant Staphylococcus aureus infections in spinal cord injury units

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) health care-associated infections (HAIs) are a concern in the 22 acute care Veterans Affairs (VA) spinal cord injury units where patients with unique rehabilitation and medical needs and a high risk of infection are treated.

METHODS

A bundle was implemented in VA spinal cord injury units consisting of nasal surveillance for MRSA on admission/in-hospital transfer/discharge, contact precautions for patients colonized or infected with MRSA, an emphasis on hand hygiene, and an institutional culture change where infection control became everyone's responsibility.

RESULTS

From October 2007, through June 2011, there were 51,627 admissions/transfers/discharges and 816,254 patient-days of care in VA spinal cord injury units. The percentage of patients screened increased to >95.0%. The mean admission MRSA prevalence was 38.6% ± 19.1%. Monthly HAI rates declined 81% from 1.217 per 1,000 patient-days to 0.237 per 1,000 patient-days (P < .001). Bloodstream infections declined by 100% (P = .002), skin and soft-tissue infections by 60% (P = .007), and urinary tract infections by 33% (P = .07).

CONCLUSION

Universal surveillance, contact precautions, hand hygiene, and an institutional culture change was associated with significant declines in MRSA HAIs in a setting with a high prevalence of MRSA colonization and a high risk for infection.