Efficacy of carbapenem vs non carbapenem β-lactam therapy as empiric antimicrobial therapy in patients with extended-spectrum β-lactamase-producing Enterobacterales urinary septic shock: a propensity-weighted multicenter cohort study

BACKGROUND

The rise in antimicrobial resistance is a global threat responsible for about 33,000 deaths in 2015 with a particular concern for extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) and has led to a major increase in the use of carbapenems, last-resort antibiotics.

METHODS

In this retrospective propensity-weighted multicenter observational study conducted in 11 ICUs, the purpose was to assess the efficacy of non carbapenem regimen (piperacillin-tazobactam (PTZ) + aminoglycosides or 3rd-generation cephalosporin (3GC) + aminoglycosides) as empiric therapy in comparison with carbapenem in extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) urinary septic shock. The primary outcome was Day-30 mortality.

RESULTS

Among 156 patients included in this study, 69 received a carbapenem and 87 received non carbapenem antibiotics as empiric treatment. Baseline clinical characteristics were similar between the two groups. Patients who received carbapenem had similar Day-30 mortality (10/69 (15%) vs 6/87 (7%), OR = 1.99 [0.55; 5.34] p = 0.16), illness severity, resolution of septic shock, and ESBL-E infection recurrence rates than patients who received an empiric non carbapenem therapy. The rates of secondary infection with C. difficile were comparable.

CONCLUSIONS

In ESBL-E urinary septic shock, empiric treatment with a non carbapenem regimen, including systematically aminoglycosides, was not associated with higher mortality, compared to a carbapenem regimen.

Dynamics of carbapenemase-producing Enterobacterales intestinal colonisation in the elderly population after hospital discharge, Italy, 2018-2020

Carbapenemase-producing Enterobacterales (CPE) represent a serious threat to public health worldwide. Elderly patients are at increased risk of colonisation/infection with CPE. This study aimed to evaluate the persistence of CPE colonisation and the genotypic characteristics of persistent strains in elderly people discharged from Italian hospitals. A longitudinal study was conducted in two Italian cities (March 2018 to September 2020) enrolling 137 patients aged ≥65 years with CPE intestinal colonisation at hospital discharge. CPE colonisation was evaluated after 4, 8 and 12 months. Competing risk analysis was used to explore the association between baseline characteristics and persistence at 4 months. For all isolates, carbapenemase typing and multilocus sequence typing were performed. Persistent isolates underwent whole-genome sequencing. Of 137 patients, 91% carried carbapenemase-producing Klebsiella pneumoniae (CP-KP) and 8.8% carried carbapenemase-producing Escherichia coli. Although a large number of patients were lost to follow-up owing to death or withdrawal, 28/65 patients (43.1%) remained colonised at Month 4; 16/42 (38.1%) and 5/28 (17.9%) were found colonised up to Months 8 and 12, respectively. Colonisation persistence was more frequent in patients with bacteraemia or complicated urinary tract infection while in hospital and in those staying in long-term care facilities (LTCFs). Clonal characteristics of CP-KP isolates did not appear to influence persistence. Isolates obtained from each persistent carrier were identical or highly related by SNP phylogenetic analysis. Identification of patients at higher risk of persistent intestinal carriage after hospital discharge can prompt control measures to limit the transmission of CPE in the community, especially in LTCF settings.

The Effect of Infection Precautions on Extended-Spectrum Beta-Lactamase Enterobacteriaceae Colonization Among Nurses in Three Beirut Hospitals

Background and objective

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) are rapidly emerging worldwide. This study aimed to assess the effect of contact precaution (CP) on ESBL-PE-colonization rates among nurses in three hospitals in Beirut, Lebanon, where ESBL is endemic, in order to define the risk factors for colonization. Accordingly, the ongoing use of CP to prevent ESBL-PE transmission to healthy nurses was evaluated.

Methods

This cross-sectional study was conducted in three hospitals. Hospital 1 required CP, Hospital 2 had recently stopped CP, and Hospital 3 had stopped it three years previously. Questionnaires and stool-collection containers were distributed to all patient care nurses in those three hospitals. The Returned samples were tested using the agar dilution technique.

Results

A total of 269 out of 733 nurses volunteered to participate; 140 met the inclusion criteria (no recent hospitalization, antibiotic use, or known ESBL-PE colonization) and provided samples. Among them, 15% were ESBL-positive. Compared to nurses from Hospital 3, nurses from Hospital 1 were 59% less likely to be colonized, while nurses from Hospital 2 were 62% more likely to be colonized.

Conclusion

In hospitals where CP is in place for ESBL-positive patients, ESBL-PE prevalence in nursing staff was significantly lower. Additionally, a work experience of two to four years increased the odds of ESBL-PE colonization in comparison with longer nursing experience. CP may be a justifiable means of protection against ESBL-PE transmission to healthy nurses. The risk factors for colonization were discontinuation of CP and a shorter clinical work experience.

Guidelines on Implementing Antimicrobial Stewardship Programs in Korea

These guidelines were developed as a part of the 2021 Academic R&D Service Project of the Korea Disease Control and Prevention Agency in response to requests from healthcare professionals in clinical practice for guidance on developing antimicrobial stewardship programs (ASPs). These guidelines were developed by means of a systematic literature review and a summary of recent literature, in which evidence-based intervention methods were used to address key questions about the appropriate use of antimicrobial agents and ASP expansion. These guidelines also provide evidence of the effectiveness of ASPs and describe intervention methods applicable in Korea.

Escalating antimicrobial resistance among Enterobacteriaceae: focus on carbapenemases

Introduction: Over the past few decades, antimicrobial resistance (AMR) has skyrocketed globally among bacteria within the Family Enterobacteriaceae (i.e. Enterobacter spp, Klebsiella spp, Escherichia coli, Proteus spp, Serratia marcescens, Citrobacter spp, and others). Enterobacteriaceae are intestinal flora and are important pathogens in nosocomial and community settings. Enterobacteriaceae spread easily between humans and may acquire AMR via plasmids or other mobile resistance elements. The emergence and spread of multidrug resistant (MDR) clones have greatly limited therapeutic options. Some infections are untreatable with existing antimicrobials.Areas covered: The authors discuss the escalation of CRE globally, the epidemiology and outcomes of CRE infections, the optimal therapy, and the potential role of several new antimicrobials to combat MDR organisms. An exhaustive search for literature related to Enterobacteriaceae was performed using PubMed, using the following key words: antimicrobial resistance; carbapenemases; Enterobacterales; Enterobacteriaceae; Klebsiella pneumoniae; Escherichia coli; global epidemiology; metallo-β-lactamases; multidrug resistance; New Delhi Metalloproteinase-1 (NDM-1); plasmidsExpert opinion: Innovation and development of new classes of antibacterial agents are critical to expand effective therapeutic options. The authors encourage the judicious use of antibiotics and aggressive infection-control measures are essential to minimize the spread of AMR.

Populations of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae are different in human-polluted environment and food items: a multicentre European study

OBJECTIVES

To assess the extent to which food items are a source of extended-spectrum β-lactamase (ESBL) -producing Escherichia coli (ESBL-Ec) and ESBL-producing Klebsiella pneumoniae (ESBL-Kp) for humans in five European cities.

METHODS

We sampled 122 human polluted (hp)-environments (sewers and polluted rivers, as a proxy of human contamination) and 714 food items in Besançon (France), Geneva (Switzerland), Sevilla (Spain), Tübingen (Germany) and Utrecht (The Netherlands). A total of 254 ESBL-Ec and 39 ESBL-Kp isolates were cultured. All genomes were fully sequenced to compare their sequence types (ST) and core genomes, along with the distribution of bla_ESBL genes and their genetic supports (i.e. chromosome or plasmid).

RESULTS

Sequence data revealed that ESBL-Ec and ESBL-Kp isolates from hp-environments were genetically different from those contaminating food items. ESBL-Ec ST131 was widespread in the hp-environment (21.5% of the isolates) but absent from the food items tested. ESBL-Ec ST10 was in similar proportions in hp-environments and food items (15 and 10 isolates, respectively) but mostly carried reservoir-specific bla_ESBL. bla_CTX-M-1 and bla_SHV-12 predominated in food-related E. coli isolates (32% and 34% of the isolates, respectively), whereas bla_CTX-M-15 and bla_CTX-M-27 predominated in isolates from hp-environments (52% and 15% of the isolates, respectively).

CONCLUSIONS

We found a very limited connection between ESBL-Ec and ESBL-Kp populations retrieved in food items and from hp-environments and bla_ESBL. This suggests that human-to-human contamination, rather than the food chain, is possibly the most frequent route of ESBL-Ec and ESBL-Kp transmission in high-income countries.

Prevention of the spread of multidrug-resistant organisms in nursing homes

The increase in the aged population led to a global rise in the demand for elderly healthcare services, such as long-term care facilities (LTCFs), nursing homes, residential homes. Unfortunately, the spread of multidrug-resistant organisms (MDROs) in these structures represent an urgent public health threat requiring immediate action. The aim of this review is to provide a practice guide for the prevention of infections in European LTCFs. A team of experts identify specific problems and proposed practical solutions for the management of colonized and infected patients residing in LTCFs. The heterogeneity of LTCF represents one of the main problems for the implementation of standardized surveillance and infection control programs. Crucial steps involved in the spread of infections among LTCF residents are represented by patient's accommodation, MDRO screening on admission, management of patients with rectal colonization by MDROs, management of patients at high risk of MDRO infections, MDRO transmission by staff and implementation of antimicrobial stewardship. Efforts to implement specific actions in each of these fields are required to reduce the infections in this setting.

Impact of the beta-lacta test on the management of urinary tract infections at the emergency department

INTRODUCTION

Rapid detection of extended-spectrum β-lactamases is essential. In this study, we evaluated the potential impact of β-lacta test on both the times to appropriate antibiotic therapy and to the implementation of patient isolation measures.

PATIENTS AND METHODS

We included prospectively all the patients admitted to the emergency department for clinical suspicion of urinary tract infection. Compared with physician's decision, we analysed the potential impact of β-lacta test on the initial antibiotic therapy and on the implementation of hygiene measures. This study has been registered under number NCT02897609.

RESULTS

We included 203 patients, 43% with acute pyelonephritis and 21% with acute prostatitis. The β-lacta test had a 95.2% sensitivity and a 99.5% specificity to detect extended-spectrum β-lactamases. Taking the β-lacta test results into account would have decreased significantly both the times to appropriate therapy and to isolation measures from 54 to 2.7 h and from 55.2 to 2.6 h, respectively.

CONCLUSION

The β-lacta test could reduce significantly the times to appropriate therapy and implementation of isolations measures.

Recommendations for the surveillance of multidrug-resistant bacteria in Italian long-term care facilities by the GLISTer working group of the Italian Association of Clinical Microbiologists (AMCLI)

Long-term care facilities (LTCFs) are an important reservoir of multidrug-resistant organisms (MDROs). Colonization of LTCF residents by MDROs is generally higher in Italy compared to other European countries. The present review by the working group for the study of infections in LTCFs (GLISTer) of the Italian Association of Clinical Microbiologists (AMCLI) aims to propose criteria for a laboratory-based surveillance of MDROs in Italian LTCFs.We recommend the adhesion to three levels of laboratory-based MDROs surveillance in LTCFs: i) mandatory MDRO surveillance by cumulative retrospective analysis of antimicrobial susceptibility data, obtained as part of routine care of clinical specimens. ii) strongly recommended surveillance by active rectal swab cultures or molecular screening to determine colonization with carbapenemase-producing Enterobacterales, should a resident be proven infected. iii) voluntary surveillance by prospective MDRO surveys, mainly based on point prevalence colonization studies, allowing to determine the MDROs baseline prevalence in the facility.Laboratory-based surveillance of MDROs in LTCFs is aimed at providing useful epidemiological information to healthcare providers operating in the facility, but it is only effective if the collected data are used for infection prevention and control purposes, targeting the peculiar aspects of LTCFs.

Elevated urine IL-10 concentrations associate with Escherichia coli persistence in older patients susceptible to recurrent urinary tract infections

Background

Age is a significant risk factor for recurrent urinary tract (rUTI) infections, but the clinical picture is often confused in older patients who also present with asymptomatic bacteriuria (ASB). Yet, how bacteriuria establishes in such patients and the factors underpinning and/or driving symptomatic UTI episodes are still not understood. To explore this further a pilot study was completed in which 30 male and female community based older patients (mean age 75y) presenting clinically with ASB / rUTIs and 15 control volunteers (72y) were recruited and monitored for up to 6 months. During this period symptomatic UTI episodes were recorded and urines collected for urinary cytokine and uropathogenic Escherichia coli (UPEC) analyses.

Results

Eighty-six per cent of patients carried E. coli (10² ≥ 10⁵ CFU/ml urine) at some point throughout the study and molecular typing identified 26 different E. coli strains in total. Analyses of urine samples for ten different cytokines identified substantial patient variability. However, when examined longitudinally the pro-inflammatory markers, IL-1 and IL-8, and the anti-inflammatory markers, IL-5 and IL-10, were significantly different in the patient urines compared to those of the controls (P < 0.0001). Furthermore, analysing the cytokine data of the rUTI susceptible cohort in relation to E. coli carriage, showed the mean IL-10 concentration to be significantly elevated (P = 0.04), in patients displaying E. coli numbers ≥10⁵ CFU/ml.

Conclusions

These pilot study data suggest that bacteriuria, characteristic of older rUTI patients, is associated with an immune homeostasis in the urinary tract involving the synthesis and activities of the pro and anti-inflammatory cytokines IL-1, IL-5, IL-8 and IL-10. Data also suggests a role for IL-10 in regulating bacterial persistence.

Multidrug-resistant infections in long-term care facilities: extended-spectrum β-lactamase-producing Enterobacteriaceae and hypervirulent antibiotic resistant Clostridium difficile

Infections due to multidrug-resistant (MDR) organisms in long-term care facilities (LTCFs) residents constitute a public health concern. This multicenter study investigated the frequency of ESBL-producing pathogens and MDR Clostridium difficile in clinical specimens from LTCF residents in Italy. During October 2014-March 2015, all urine and diarrheic fecal samples from LTCF residents (≥65 years) with suspected urinary tract infection or C. difficile infection, respectively, received for diagnosis by 4 hospital laboratories located in different cities were analyzed. Antibiotic susceptibility testing, characterization of resistance genes, and molecular typing of pathogens were performed. Of 806 urine cultures collected from 626 residents at 44 different LTCFs, 492 were positive for microbial infection. Of these, 158 were positive for at least an ESBL-producing Enterobacteriaceae species (32.1%), with Escherichia coli as the most frequent ESBL pathogen (23.4%) followed by Klebsiella pneumoniae (4.5%). Furthermore, 4 carbapenemase producers (0.8%) (1 E. coli with VIM-1and 3 K. pneumoniae with KPC-3) were detected. The CTX-M-15 type ESBL predominated in both E. coli (71.3%) and K. pneumoniae (77.3%). Most E. coli isolates (82.6%) belonged to the ST131/H30 clone/subclone. For K. pneumoniae, ST307 and ST15 were frequent (31.8% and 22.7%, respectively), but isolates harboring bla_KPC-3 belonged to CC258. Of 136 diarrheic fecal samples collected from 111 residents at 26 different LTCFs, 21 (15.4%) were positive for toxigenic C. difficile; of these, 13 (62%) were MDR (resistant to 3 or more antimicrobial agents of different classes). The predominant C. difficile polymerase chain reaction ribotype was 356/607 (42.9%), followed by 018, 449, and 078 (14% each). Public health efforts are needed to contain the diffusion of CTX-M-producing Enterobacteriaceae and MDR C. difficile in LTCF settings.

Frequency of Multidrug-Resistant Organisms Cultured From Urine of Children Undergoing Clean Intermittent Catheterization

BACKGROUND

Children undergoing CIC frequently have positive urine culture results and receive many antimicrobial agents. Subsequently, this population is at high risk for infections caused by antimicrobial-resistant bacteria. Resistant pathogens, such as vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Enterobacteriaceae (CRE), and organisms that produce extended-spectrum β-lactamases (ESBLs), which are third-generation cephalosporin resistant (3GCR), are of particular concern.

METHODS

In this retrospective study, all urine culture results and antimicrobial-susceptibility testing results were obtained between January 2008 and December 2014 from the electronic health record of children ≤18 years of age who were undergoing CIC (n = 14 832). Isolates were identified as VRE, CRE, or 3GCR. Organisms of the same type that were obtained in the same year and with identical antibiotic susceptibilities from the same patient were excluded. Simple linear regression was used to determine the association between year and rates of resistance.

RESULTS

A total of 3997 positive culture results were included in this analysis. Of all Enterococcus isolates for which susceptibility results were available, 4.6% were VRE, 11.1% of all isolates that belonged to the Enterobacteriaceae family were 3GCR, and 0.4% of eligible isolates were CRE. There were significantly higher rates of resistance to third-generation cephalosporins and CRE in 2014 than in 2008 (P < .01). Simple linear regression revealed a significant association between year and rate for resistance to third-generation cephalosporins but not for CRE or VRE. The rate of increase in resistance to third-generation cephalosporins in patients who required CIC was higher than that in patients who did not need CIC.

CONCLUSIONS

The rate of resistance to third-generation cephalosporins has increased significantly in the past 7 years in children undergoing CIC, which indicates that careful monitoring is warranted for continued increases in antimicrobial-resistant organisms in this unique patient population.

Antibacterial Prophylaxis for Surgical Site Infection in the Elderly: Practical Application

Surgical site infections are among the most common healthcare-associated infections and are linked with increased length of hospitalization, re-admission, mortality and significant financial burden. Risk factors for the occurrence of surgical site infections include variables related to the surgical procedure as well as host factors. Increasing age is associated with the occurrence of surgical site infections. The aim of this review is to give an update on the antibiotic prophylaxis for surgical site infection in elderly people. We focused on specific issues and practical applications, such as the importance of targeting the antimicrobial agent to the susceptibility pattern of colonizing flora in selected cases and the need for dosage modifications.

Comparison of rates of fecal colonization with extended-spectrum beta-lactamase-producing enterobacteria among patients in different wards, outpatients and medical students

Because asymptomatic carriage of extended-spectrum beta-lactamase (ESBL) producers is a risk factor for infection, data on colonization dynamics are important when planning infection control. This study investigated fecal colonization with ESBL producers among inpatients, outpatients and medical students and compares the characteristics of ESBL producers among these groups. Carriage rates were investigated in 5581 fecal samples; 4343 from inpatients (330, 1397, 619 and 1864 from adult ICUs [intensive care units], adult non-ICUs, pediatric ICUs and pediatric non-ICUs, respectively), 814 from outpatients and 424 from screening of medical students. ESBL producers were characterized by co-resistance, integrons carried, and aminoglycoside resistance and ESBL genes. Dynamic regression models were built to identify relationships between combinations of time series of monthly antibiotic consumption, prevalence of carriers and infected subjects. Inpatients, ICU patients and adults showed higher prevalence than outpatients, non-ICU patients or children (7.4%, 9.3% and 12.0% vs. 3.1%, 6.1% and 4.1%, respectively). Klebsiella pneumoniae was more frequent in ICU patients; dominance of CTX-M-15 producers was more marked in adult than in pediatric inpatients. ESBL carriage was shown to be a consequence of infection in adults in the time-series analysis; antibiotic consumption had little effect. The epidemiology of colonization with ESBL producers differed between pediatric ICU, adult ICU and adult non-ICU patients. In adults, carriage of ESBL producers seems to be the consequence of infection, especially in ICU patients; the main source of colonization is nosocomial acquisition. In contrast, children are less likely to acquire colonizer strains in hospitals; importation of ESBL producers by colonized children seems to be significant.

Review on colonization of residents and staff in Italian long-term care facilities by multidrug-resistant bacteria compared with other European countries

BACKGROUND

Rates of colonization and infection with multidrug-resistant (MDR) bacteria are increasing worldwide, in both acute care hospitals and long-term care facilities (LTCFs). Italy has one of the highest prevalence of MDR bacteria in European countries, especially with regard to methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL) or carbapenemase producing Enterobacteriaceae (CPE).

METHOD

Review of studies on colonization by MDR bacteria from Italian LTCFs, risk factors for colonization and molecular characteristics of surveillance and clinical isolates, compared with other European countries.

RESULTS

High variability of MDR colonization has been reported within and especially between European countries. Only a few surveillance studies have been performed in Italian LTCFs; these show MRSA colonization prevalence of 7.8-38.7 % for residents and 5.2-7.0 % for staff members, ESBL prevalence of 49.0-64.0 % for residents and 5.2-14.5 % for staff and prevalence of CPE of 1.0-6.3 % for residents and 0.0-1.5 % for staff. In Italian LTCFs, as well as in other European countries, the most prevalent ESBLs from surveillance or clinical Escherichia coli isolates were found to be CTX-M-type enzymes, particularly CTX-M-15, expressed by the pandemic ST131 clonal group; this lineage also expresses carbapenemase genes of the blaVIM and blaKPC types. Various risk factors for colonization of residents by MDR bacteria were identified.

CONCLUSIONS

The limited data from Italian LTCFs confirms these settings as important reservoirs for MDR organisms, allowing important considerations regarding the infection risk by these organisms. Nevertheless, more extended and countrywide screening studies for MDR colonization in Italian LTCFs are required. To promote further studies of various microbiological aspects related to LTCFs, the Association of Italian Clinical Microbiologists (Associazione Microbiologi Clinici Italiani; AMCLI) in 2016 has set up a new Working Group for the Study of Infections in LTCFs (Gruppo di Lavoro per lo Studio delle Infezioni nelle Residenze Sanitarie Assistite e Strutture Territoriali assimilabili; GLISTer), consisting of Clinical Microbiologists represented by the authors of this review article.

Clinical Characteristics, Diagnostic Evaluation, and Antibiotic Prescribing Patterns for Skin Infections in Nursing Homes

BACKGROUND

The epidemiology and management of skin infections in nursing homes has not been adequately described. We reviewed the characteristics, diagnosis, and treatment of skin infections among residents of nursing homes to identify opportunities to improve antibiotic use.

METHODS

This was a retrospective study involving 12 nursing homes in the Denver metropolitan area. For residents at participating nursing homes diagnosed with a skin infection between July 1, 2013 and June 30, 2014, clinical and demographic information was collected through manual chart review.

RESULTS

Of 100 cases included in the study, the most common infections were non-purulent cellulitis (n = 55), wound infection (n = 27), infected ulcer (n = 8), and cutaneous abscess (n = 7). In 26 cases, previously published minimum clinical criteria for initiating antibiotics (Loeb criteria) were not met. Most antibiotics (n = 52) were initiated as a telephone order following a call from a nurse, and 41 patients were not evaluated by a provider within 48 h after initiation of antibiotics. Nearly all patients (n = 95) were treated with oral antibiotics alone. The median treatment duration was 7 days (interquartile range 7-10); 43 patients received treatment courses of ≥10 days.

CONCLUSION

Most newly diagnosed skin infections in nursing homes were non-purulent infections treated with oral antibiotics. Antibiotics were initiated by telephone in over half of cases, and lack of a clinical evaluation within 48 h after starting antibiotics was common. Improved diagnosis through more timely clinical evaluations and decreasing length of therapy are important opportunities for antibiotic stewardship in nursing homes.

Cleaning, resistant bacteria, and antibiotic prescribing in residential aged care facilities

Residents of residential aged care facilities (RACFs) are at risk of colonization and infection with multidrug-resistant bacteria, and antibiotic prescribing is often inappropriate and not based on culture-proven infection. We describe low levels of resident colonization and environmental contamination with resistant gram-negative bacteria in RACFs, but high levels of empirical antibiotic use not guided by microbiologic culture. This research highlights the importance of antimicrobial stewardship and environmental cleaning in aged care facilities.

STROBE-AMS: recommendations to optimise reporting of epidemiological studies on antimicrobial resistance and informing improvement in antimicrobial stewardship

OBJECTIVES

To explore the accuracy of application of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) tool in epidemiological studies focused on the evaluation of the role of antibiotics in selecting resistance, and to derive and test an extension of STROBE to improve the suitability of the tool in evaluating the quality of reporting in these area.

METHODS

A three-step study was performed. First, a systematic review of the literature analysing the association between antimicrobial exposure and acquisition of methicillin-resistant Staphylococcus aureus and/or multidrug-resistant Acinetobacter baumannii was performed. Second, articles were reviewed according to the STROBE checklist for epidemiological studies. Third, a set of potential new items focused on antimicrobial-resistance quality indicators was derived through an expert two-round RAND-modified Delphi procedure and tested on the articles selected through the literature review.

RESULTS

The literature search identified 78 studies. Overall, the quality of reporting appeared to be poor in most areas. Five STROBE items, comprising statistical analysis and study objectives, were satisfactory in <25% of the studies. Informative abstract, reporting of bias, control of confounding, generalisability and description of study size were missing in more than half the articles. A set of 21 new items was developed and tested. The new items focused particularly on the study setting, antimicrobial usage indicators, and patients epidemiological and clinical characteristics. The performance of the new items in included studies was very low (<25%).

CONCLUSIONS

Our paper reveals that reporting in epidemiological papers analysing the association between antimicrobial usage and development of resistance is poor. The implementation of the newly developed STROBE for antimicrobial stewardship (AMS) tool should enhance appropriate study design and reporting, and therefore contribute to the improvement of evidence to be used for AMS programme development and assessment.

Epidemiology of CTX-M-type extended-spectrum β-lactamase-producing Escherichia coli among older adults

To identify independent predictors for isolation of CTX-M-type extended-spectrum β-lactamase-producing Escherichia coli (CTX-M E coli) in older adults (>65 years old), 87 cases with CTX-M E coli isolation were compared with matched controls without E coli isolation. Institutionalized residence, multiple comorbidities, and urinary catheter were independent predictors of CTX-M E coli among older adults.

Antibiotic resistance patterns of bacteria causing urinary tract infections in the elderly living in nursing homes versus the elderly living at home: an observational study

Background

Antibiotic resistance is a problem in nursing homes. Presumed urinary tract infections (UTI) are the most common infection. This study examines urine culture results from elderly patients to see if specific guidelines based on gender or whether the patient resides in a nursing home (NH) are warranted.

Methods

This is a cross sectional observation study comparing urine cultures from NH patients with urine cultures from patients in the same age group living in the community.

Results

There were 232 positive urine cultures in the NH group and 3554 in the community group. Escherichia coli was isolated in 145 urines in the NH group (64 %) and 2275 (64 %) in the community group. There were no clinically significant differences in resistance.

Combined, there were 3016 positive urine cultures from females and 770 from males. Escherichia coli was significantly more common in females 2120 (70 %) than in males 303 (39 %)(p < 0.05). Enterococcus faecalis was significantly less common in females 223(7 %) than males 137 (18 %) (p < 0.05). For females, there were lower resistance rates to ciprofloxacin among Escherichia coli (7 % vs 12 %; p < 0.05) and to mecillinam among Proteus mirabilis (3 % vs 12 %; p < 0.05).

Conclusions

Differences in resistance rates for patients in the nursing home do not warrant separate recommendations for empiric antibiotic therapy, but recommendations based on gender seem warranted.

Biofilm-based infections in long-term care facilities

The recent trend in the early admittance to long-term care facilities (LTCFs) of severely injured patients transferred from general hospitals has given a new dynamic to the incidence of healthcare-associated infections, including biofilm-based infections related to the implant of urinary and intravascular catheters, and the onset of pressure ulcers. Catheter-associated urinary tract infections lead in most of the surveys on LTCFs, approximately 80% of urinary tract infections in these settings being due to the short- or long-term insertion of a urinary catheter. Furthermore, the implantation of intravascular catheters is often responsible for catheter-related bloodstream infections caused by the development of an intraluminal biofilm. Pressure ulcers, frequently occurring in bedridden patients admitted to LTCFs, are also susceptible to infection by biofilm-growing aerobic and anaerobic bacteria, the biofilm formation on the wound being the main reason for its delayed healing.

Strategies and challenges of antimicrobial stewardship in long-term care facilities

As people are living longer the demand for long-term care facilities (LTCFs) continues to rise. For many reasons, antimicrobials are used intensively in LTCFs, with up to a half of this use considered inappropriate or unnecessary. Over-use of antimicrobials can have direct adverse consequences for LTCF residents and promotes the development and spread of resistant bacteria. It is therefore critical that LTCFs are able to engage in antimicrobial stewardship programmes, which have the potential to minimize the antibiotic selective pressure, while improving the quality of care received by LTCF residents. To date, no antimicrobial stewardship guidelines specific to LTCF settings have been published. Here we outline the scale of antimicrobial use in LTCFs and the underlying drivers for antibiotic over-use. We further describe the particular challenges of antimicrobial stewardship in LTCFs, and review the interventional studies that have aimed to improve antibiotic use in these settings. Practical recommendations are then drawn from this research to help guide the development and implementation of antimicrobial stewardship programmes.

Catheter-related urinary tract infection: practical management in the elderly

From 5-10% of elderly residents of long-term care facilities require chronic indwelling catheters for management of urine voiding. These residents are always bacteriuric, because of biofilm formation along the catheter, and experience increased morbidity associated with urinary tract infection. A wide variety of bacteria or yeast species are isolated. Occasional episodes of symptomatic infection may be accompanied by localizing genitourinary findings. However, when fever is present and there are no localizing findings, symptomatic infection is a diagnosis of exclusion. Many of these episodes are not from a urinary source, so critical clinical evaluation is always necessary. A urine specimen for culture should be obtained from patients with symptomatic infection prior to institution of antimicrobial therapy. When the catheter has been present for 2 weeks or longer, it should be replaced and the urine specimen collected through the new catheter. This provides a specimen of bladder urine without biofilm contamination, and catheter replacement also improves clinical outcomes. Treatment algorithms with a goal of limiting inappropriate treatment of asymptomatic bacteriuria have been developed. Empiric antimicrobial therapy should be avoided when possible. Guidelines for prevention of catheter-acquired urinary infection should be followed. The most important of these is to avoid use of a urinary catheter whenever possible and, when there is no longer an indication for the catheter, to remove it promptly.

Inguinal skin colonization with multidrug-resistant bacteria among residents of elderly care facilities: frequency, persistence, molecular analysis and clinical impact

Frequency, persistence and molecular characteristics of multidrug resistant bacteria colonizing inhabitants of long term care facilities are topics of current concern. We performed a point-prevalence survey of 402 residents in 7 elderly care facilities in Berlin, Germany. Inguinal swabs were analyzed for the presence of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), and multidrug-resistant gram-negative bacteria. Three and six months following the initial investigation, all colonized residents were sampled again and the occurrence of intercurrent infections, hospital admissions and use of antimicrobials were registered. Genetic relatedness of the bacteria was investigated using multi-locus sequence typing (MLST), spa-typing and SmaI/XbaI-macrorestriction analysis. 33 (8.2%) residents were skin-colonized with multidrug-resistant bacteria. MRSA were found in 19 (4.7%) and ESBL-producing Enterobacteriaceae in 16 residents (3.98%). Independent risk factors for colonization with multidrug-resistant bacteria were a high level of care and the presence of chronic wounds. A large proportion of the observed bacteria persisted up to six months and showed a high degree of inter-individual diversity. Outcome analysis revealed that infections tend to occur slightly more often in residents colonized by multiresistant pathogens. We assume that a perceptible population of residents in nursing homes is at risk for individual colonization with multidrug-resistant bacteria as well as healthcare associated infections.

Distribution and antimicrobial susceptibility profile of extended-spectrum β-lactamase-producing Proteus mirabilis strains recently isolated in Japan

Here we report on the prevalence of extended-spectrum β-lactamase (ESBL)-producing Proteus mirabilis from a nationwide antimicrobial resistance survey in different geographical regions of Japan. A total of 799 P. mirabilis isolates recovered between July 2009 and June 2010 from 314 healthcare facilities were characterised according to ESBL production, source, location and antimicrobial susceptibility pattern. ESBL production was found in 364 (45.6%) of the isolates, among which 354 (97.3%) produced CTX-M-2 group β-lactamases. Of the 349 ESBL-producing isolates in which the inpatient or outpatient status of the source was known, 324 (92.8%) were from inpatients and 25 (7.2%) were from outpatients (P<0.05). Results of pulsed-field gel electrophoresis (PFGE) analysis performed on 66 of the ESBL-producers generated a distribution of PFGE patterns into 21 groups. Genetic relatedness was seen among isolates within a region, which is consistent with horizontal transmission. With respect to the frequency of ESBL-producers by specimen source, 12/14 (85.7%) central venous catheter specimens yielded ESBL-producing P. mirabilis compared with 159/405 (39.3%), 119/209 (56.9%), 42/77 (54.5%) and 20/49 (40.8%), respectively, for isolates from urine, sputum, decubitus ulcer and wound specimens. Among the ESBL-producers, non-susceptibility to ciprofloxacin was found in 74.2% of the ESBL-producing isolates compared with 17.7% of the ESBL-non-producing isolates. These results show that approximately one-half of the P. mirabilis isolates from clinical specimens in Japan are ESBL-producers and that the potential for concomitant fluoroquinolone resistance must also be considered.

Antimicrobial stewardship in residential aged care facilities: need and readiness assessment

Background

Information about the feasibility, barriers and facilitators of antimicrobial stewardship (AMS) in residential aged care facilities (RACFs) has been scant. Exploring the prevailing perceptions and attitudes of key healthcare providers towards antibiotic prescribing behaviour, antibiotic resistance and AMS in the RACF setting is imperative to guide AMS interventions.

Methods

Semi-structured interviews and focus groups were conducted with key RACF healthcare providers until saturation of themes occurred. Participants were recruited using purposive and snowball sampling. The framework approach was applied for data analysis.

Results

A total of 40 nurses, 15 general practitioners (GPs) and 6 pharmacists from 12 RACFs were recruited. Five major themes emerged; perceptions of current antibiotic prescribing behaviour, perceptions of antibiotic resistance, attitude towards and understanding of AMS, perceived barriers to and facilitators of AMS implementation, and feasible AMS interventions. A higher proportion of GPs and pharmacists compared with nurses felt there was over-prescribing of antibiotics in the RACF setting. Antibiotic resistance was generally perceived as an issue for infection control rather than impacting clinical decisions. All key stakeholders were supportive of AMS implementation in RACFs; however, they recognized barriers related to workload and logistical issues. A range of practical AMS interventions were identified, with nursing-based education, aged-care specific antibiotic guidelines and regular antibiotic surveillance deemed most useful and feasible.

Conclusions

Areas of antibiotic over-prescribing have been identified from different healthcare providers’ perspectives. However, concern about the clinical impact of antibiotic resistance was generally lacking. Importantly, information gathered about feasibility, barriers and facilitators of various AMS interventions will provide important insights to guide development of AMS programs in the RACF setting.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-410) contains supplementary material, which is available to authorized users.

Point prevalence survey of urinary catheterisation in care homes and where they were inserted, 2012

The extent to which the use of catheter care bundles and other interventions has led to a reduction in urinary catheterisation rates is unknown. We aimed to determine current urinary catheterisation rates in care homes with residents over 65 years old, and determine the extent to which residents are discharged from the hospital setting with urinary catheters. A point prevalence questionnaire survey was used in care homes that looked after residents over 65 years in six UK health boards or primary care trusts, to determine urinary catheterisation rates, and where these catheters were inserted. Questionnaires for 445 of 461 care homes (96.5%) were completed, 425 of 445 care homes cared for residents over 65 years; 888 (6.9%) of 12,827 residents had a urethral (82.5%) or supra-pubic (17.5%) urinary catheter. Over half of all catheters (both urethral and suprapubic, 57.4%, 509 of 888 catheters), and 3.1% of all residents had a catheter inserted while the residents were hospital inpatients, and then discharged back to the care home still catheterised. There was a significant variation in urinary catheterisation rates in the care homes surveyed, and rates remain similar to previous English surveys in 2003 and 2009. More still needs to be done to understand the variation in urinary catheterisation rates in care homes and reduce these rates, including the numbers of residents that are discharged from hospital with a urinary catheter.

Guidelines for the diagnosis and antimicrobial therapy of canine superficial bacterial folliculitis (Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases)

BACKGROUND

Superficial bacterial folliculitis (SBF) is usually caused by Staphylococcus pseudintermedius and routinely treated with systemic antimicrobial agents. Infection is a consequence of reduced immunity associated with alterations of the skin barrier and underlying diseases that may be difficult to diagnose and resolve; thus, SBF is frequently recurrent and repeated treatment is necessary. The emergence of multiresistant bacteria, particularly meticillin-resistant S. pseudintermedius (MRSP), has focused attention on the need for optimal management of SBF.

OBJECTIVES

Provision of an internationally available resource guiding practitioners in the diagnosis, treatment and prevention of SBF.

DEVELOPMENT OF THE GUIDELINES

The guidelines were developed by the Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases, with consultation and advice from diplomates of the American and European Colleges of Veterinary Dermatology. They describe optimal methods for the diagnosis and management of SBF, including isolation of the causative organism, antimicrobial susceptibility testing, selection of antimicrobial drugs, therapeutic protocols and advice on infection control. Guidance is given for topical and systemic modalities, including approaches suitable for MRSP. Systemic drugs are classified in three tiers. Tier one drugs are used when diagnosis is clear cut and risk factors for antimicrobial drug resistance are not present. Otherwise, tier two drugs are used and antimicrobial susceptibility tests are mandatory. Tier three includes drugs reserved for highly resistant infections; their use is strongly discouraged and, when necessary, they should be used in consultation with specialists.

CONCLUSIONS AND CLINICAL IMPORTANCE

Optimal management of SBF will improve antimicrobial use and reduce selection of MRSP and other multidrug-resistant bacteria affecting animal and human health.

Impact of extended-spectrum β-lactamase-producing organisms on clinical and economic outcomes in patients with urinary tract infection

OBJECTIVE

To compare clinical and economic outcomes between patients with urinary tract infection (UTI) due to extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella species (ESBL-EK) versus patients with non-ESBL-EK UTI.

PATIENTS AND METHODS

Eighty-four (3.6%) of 2345 patients admitted between September 1, 2011 and August 31, 2012 with UTI were positive for ESBL-EK. Fifty-five ESBL-EK UTI (cases) and matched controls (non-ESBL-EK UTI) were included in the analysis. Clinical and economic outcomes were compared between cases and controls for statistical significance.

RESULTS

Cases were more likely to have diabetes mellitus, a history of recurrent UTIs, recently received antibiotics, recently been hospitalized, and had previous isolation of an ESBL-producing organism compared with controls. Failure of initial antibiotic regimen (62% vs 6%; P < 0.001) and time to appropriate antibiotic therapy (51 vs 2.5 hours; P < 0.001) were greater in cases. The median cost of care was greater (additional $3658; P = 0.02) and the median length of stay (LOS) prolonged for cases (6 vs 4 days; P = 0.02) despite similar hospital reimbursement (additional $469; P = 0.56). Although not significant, infection-related mortality (7.2% vs 1.8%) and 30-day UTI readmission (7.2% vs 3.6%) were higher in ESBL-EK cases.

CONCLUSIONS

UTI caused by ESBL-EK is associated with significant clinical and economic burden. The cost of care and LOS of patients with ESBL-EK UTI were 1.5 times those caused by non-ESBL-EK. Importantly, the additional cost of care is a liability to the hospital, as this is not offset by reimbursement. Appropriate and timely initial antibiotics may minimize the ESBL-EK impact on outcomes of patients with UTI.

Changing epidemiology of infections due to extended spectrum beta-lactamase producing bacteria

Background

Community-associated infections caused by extended-spectrum beta-lactamase (ESBL) producing bacteria are a growing concern.

Methods

Retrospective cohort study of clinical infections due to ESBL-producing bacteria requiring admission from 2006-2011 at a tertiary care academic medical center in Providence, RI.

Results

A total of 321 infections due to ESBL-producing bacteria occurred during the study period. Fifty-eight cases (18%) were community-acquired, 170 (53%) were healthcare–associated, and 93 (29%) were hospital-acquired. The incidence of ESBL infections per 10,000 discharges increased during the study period for both healthcare-associated infections, 1.9 per year (95% CI 1-2.8), and for community-acquired infections, 0.85 per year (95% CI 0.3-1.4) but the rate remained unchanged for hospital-acquired infections. For ESBL-producing E. coli isolates, resistance to both ciprofloxacin and trimethoprim-sulfamethoxazole was 95% and 65%, respectively but 94% of isolates were susceptible to nitrofurantoin.

Conclusions

Community-acquired and healthcare-associated infections due to ESBL-producing bacteria are increasing in our community, particularly urinary tract infections due to ESBL-producing E. coli. Most isolates are resistant to oral antibiotics commonly used to treat urinary tract infections. Thus, our findings have important implications for outpatient management of such infections.

Emergence of extended-spectrum β-lactamase-producing Escherichia coli in catheter-associated urinary tract infection in neurogenic bladder patients

BACKGROUND

Catheter-associated urinary tract infection (CAUTI) is a common clinic problem. The purpose of this study was to investigate recent trends in CAUTI in neurogenic bladder patients focusing on extended-spectrum β-lactamase (ESBL)-producing Escherichia coli.

METHODS

Isolates from the urine of neurogenic bladder patients with UTI were investigated. Nine strains of ESBL-producing E coli were assayed by molecular strain typing using the Diversilab system for repetitive-sequence-based polymerase chain reaction (rep-PCR).

RESULTS

E coli accounted for most of the bacteria (74.1% to 81.0%) that produced ESBLs. Rep-PCR data showed that 7 out of 9 ESBL-producing E coli belonged to the same typing group with high similarity (more than 97% similarity) and that this distribution corresponded with antibiotic resistance patterns.

CONCLUSION

ESBL producing E coli strains isolated from CAUTI patients could be discriminated by rep-PCR typing using the Diversilab system in consistent with antibiotic resistance patterns.

Reducing inappropriate antibiotic prescribing in the residential care setting: current perspectives

Residential aged care facilities are increasingly identified as having a high burden of infection, resulting in subsequent antibiotic use, compounded by the complexity of patient demographics and medical care. Of particular concern is the recent emergence of multidrug-resistant organisms among this vulnerable population. Accordingly, antimicrobial stewardship (AMS) programs have started to be introduced into the residential aged care facilities setting to promote judicious antimicrobial use. However, to successfully implement AMS programs, there are unique challenges pertaining to this resource-limited setting that need to be addressed. In this review, we summarize the epidemiology of infections in this population and review studies that explore antibiotic use and prescribing patterns. Specific attention is paid to issues relating to inappropriate or suboptimal antibiotic prescribing to guide future AMS interventions.

Outcome of Antimicrobial Therapy of Pediatric Urinary Tract Infections Caused by Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae

Background

The purpose of this study was to compare the outcome of carbapenem versus non-carbapenem antimicrobial therapy for pediatric urinary tract infections (UTIs) caused by extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae.

Materials and Methods

From 2006 to 2011, 42 episodes of UTI caused by ESBL-producing Enterobacteriaceae were diagnosed at Seoul National University Children's Hospital. Patients were grouped according to the antimicrobials they received into a carbapenem group and a non-carbapenem group. Medical records were retrospectively reviewed to assess treatment outcome, time to defervescence after initiation of treatment, and relapse rate.

Results

There were 36 children with 42 episodes of UTI caused by ESBL-producing Enterobacteriaceae. Twenty-seven cases (64%) had an underlying urologic disease, 28 (67%) cases were caused by Escherichia coli, and 14 (33%) cases were caused by Klebsiella pneumoniae. Four (10%) cases were treated with carbapenem, 23 cases (55%) were treated with non-carbapenem, and 15 (36%) cases were treated by switching from a carbapenem to a non-carbapenem and vice versa. There was no treatment failure at the time of antimicrobial discontinuation. Between the carbapenem and the non-carbapenem treatment groups, there were no significant differences in bacterial etiology (P = 0.59), time to defervescence after the initiation of antimicrobials (P = 0.28), and relapse rate (P = 0.50). In vitro susceptibility to non-carbapenem antimicrobials did not affect the time to defervescence after the initiation of antimicrobial treatment, and the relapse rate in the non-carbapenem group.

Conclusions

This study found no significant difference in the treatment outcome between pediatric patients treated with carbapenem and those treated with non-carbapenem antimicrobials for UTI caused by ESBL-producing Enterobacteriaceae. Therefore, the initially administered non-carbapenem can be maintained in UTI patients showing clinical improvement.

Changes in colonization of residents and staff of a long-term care facility and an adjacent acute-care hospital geriatric unit by multidrug-resistant bacteria over a four-year period

BACKGROUND

In 2012 we undertook a screening study for Enterobacteriaceae with extended-spectrum β-lactamases (ESBLs), derepressed or acquired high-level AmpC cephalosporinases, and metallo-β-lactamases (MBLs), and also methicillin-resistant Staphylococcus aureus (MRSA), in a long-term care facility (LTCF1) and the associated acute care hospital geriatric ward in Bolzano, northern Italy. The study followed up an initial survey carried out in LTCF1 in 2008. For comparison, screening in 2012 was extended to a second LTCF.

METHODS

Urine samples and rectal, inguinal, oropharyngeal, and nasal swabs were plated on selective agars. Isolates were typed by pulsed-field gel electrophoresis. Resistance genes and Escherichia coli belonging to ST131 were sought by PCR. Demographic data were collected.

RESULTS

Fewer residents of LTCF1 were colonized with multidrug-resistant (MDR) bacteria in 2012: all MDR organisms, 53.8% vs 74.8% in 2008; ESBL producers, 49.0% vs 64.0% in 2008; MRSA, 13.2% vs 38.7% in 2008; only 2 MBL-producers were isolated in 2012 vs 8 in 2008. Colonization of staff in LTCF1 by MDR bacteria had also decreased (overall 10.5% in 2012 vs 27.5% in 2008). Changed case mixes and risk factors, together with strengthened hygiene measures probably underlie the changes. Colonization proportions in 2012 in LTCF2 were similar to those in LTCF1. By contrast there was no significant change in the proportion of patients colonized by MDR bacteria in the geriatric ward (22.2% in 2008 vs 22.7% in 2012).

CONCLUSIONS

A significant decrease in the proportions of staff and residents of an LTCF colonized by MDR bacteria was observed over a 4-y interval.