Impact of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species on clinical outcomes and hospital costs: a matched cohort study

The burden of antibiotic resistance of the main microorganisms causing infections in humans - review of the literature

One of the biggest threats to human well-being and public health is antibiotic resistance. If allowed to spread unchecked, it might become a major health risk and trigger another pandemic. This proves the need to develop antibiotic resistance-related global health solutions that take into consideration microdata from various global locations. Establishing positive social norms, guiding individual and group behavioral habits that support global human health, and ultimately raising public awareness of the need for such action could all have a positive impact. Antibiotic resistance is not just a growing clinical concern but also complicates therapy, making adherence to current guidelines for managing antibiotic resistance extremely difficult. Numerous genetic components have been connected to the development of resistance; some of these components have intricate paths of transfer between microorganisms. Beyond this, the subject of antibiotic resistance is becoming increasingly significant in medical microbiology as new mechanisms underpinning its development are identified. In addition to genetic factors, behaviors such as misdiagnosis, exposure to broad-spectrum antibiotics, and delayed diagnosis contribute to the development of resistance. However, advancements in bioinformatics and DNA sequencing technology have completely transformed the diagnostic sector, enabling real-time identification of the components and causes of antibiotic resistance. This information is crucial for developing effective control and prevention strategies to counter the threat.

Nano-Emulsified Perfluorooctyl Bromide Can Infiltrate Gram-Negative Bacteria and Sensitize Them to Ultrasound

Gram-negative (G-) bacterial infections remain one of the most urgent global health threats, because the distinctive envelope structure hinders the penetration of therapeutics. Here, we showed that a perfluorooctyl bromide nanoemulsion (PFOB NE) uniquely interacts with G- bacteria. After cell envelope attachment, the PFOB can infiltrate the cell and was diffused throughout. In this process, it impaired the membranes by disintegrating phospholipid molecules, enhancing the consequent ultrasonic cavitation to break the envelope. We identified through ultrasound that the NE had remarkable bactericidal effects against various antibiotic-resistant pathogens. Using in situ sterilization, this approach accelerated the recovery of bacteria-infected murine skin wounds. Thus, combining PFOB and ultrasound might be an alternative tool for conquering the growing threat of G- pathogens.

Extended Spectrum β-Lactamase-Producing Enterobacterales of Shrimp and Salmon Available for Purchase by Consumers in Canada-A Risk Profile Using the Codex Framework

The extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-EB) encompass several important human pathogens and are found on the World Health Organization (WHO) priority pathogens list of antibiotic-resistant bacteria. They are a group of organisms which demonstrate resistance to third-generation cephalosporins (3GC) and their presence has been documented worldwide, including in aquaculture and the aquatic environment. This risk profile was developed following the Codex Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance with the objectives of describing the current state of knowledge of ESBL-EB in relation to retail shrimp and salmon available to consumers in Canada, the primary aquacultured species consumed in Canada. The risk profile found that Enterobacterales and ESBL-EB have been found in multiple aquatic environments, as well as multiple host species and production levels. Although the information available did not permit the conclusion as to whether there is a human health risk related to ESBLs in Enterobacterales in salmon and shrimp available for consumption by Canadians, ESBL-EB in imported seafood available at the retail level in Canada have been found. Surveillance activities to detect ESBL-EB in seafood are needed; salmon and shrimp could be used in initial surveillance activities, representing domestic and imported products.

Criteria Restricting Inappropriate Meropenem Empiricism (CRIME): a quasi-experimental carbapenem restriction pilot at a large academic medical centre

The broad-spectrum activity of carbapenems makes them appealing for empirical use; however, they are associated with development of Clostridioides difficile infection (CDI) and multidrug resistance. Selective carbapenem use is vital in maintaining their effectiveness. We examined the impact of meropenem restriction criteria on utilisation and patient outcomes. This quasi-experimental study was conducted at a single academic medical centre after medication use evaluation found frequent inappropriate meropenem utilisation. Antimicrobial stewardship-led restriction criteria were developed and implemented in February 2022. Investigators aimed to determine how restriction criteria affected meropenem utilisation across 8 weeks in the pre- (February-April 2020) versus post-implementation period (February-April 2022). The primary outcome was inappropriateness of meropenem utilisation. Secondary outcomes included days of therapy per 1000 patient-days (DOT/1000 PD), hospital length of stay (LOS), CDI Standardized Infection Ratio (SIR), and acquisition cost. Across the 8-week timeframes, reductions in inappropriate meropenem use (64.5% vs. 12.8%; P < 0.001), duration of therapy [5.8 (3.2-7.3) vs. 2.4 (1.0-5.5) days; P < 0.001] and utilisation (30.5 vs. 8.3 DOT/1000 PD; P < 0.001) pre- versus post-implementation were observed. Total meropenem orders decreased by 65% (P < 0.001). Median hospital LOS also decreased between periods [11.9 (7.8-20.4) vs. 9.2 (5.4-15.2) days], although not statistically significant (P = 0.051). There was no difference in CDI SIR (0.1 vs. 0.1; P = 0.99). Projected annual cost savings were ∼US$57 300. Implementation of antimicrobial stewardship-initiated restriction criteria can reduce inappropriate meropenem utilisation, overall number of orders, and total duration of therapy.

Healthcare-associated urinary tract infections in urology

The purpose of the present review is to report the incidence and characteristics of healthcare-associated urinary tract infections (HAUTIs) in urology with their microbiological and resistance patterns. Urinary tract infections are the main type of healthcare-associated infection in patients hospitalized in a urology ward. Patients admitted to urology departments report a high prevalence of urinary tract catheterization, up to 75% during the hospitalization period, and up to 20% had a urinary catheter before admission. An endourological surgical procedure is another risk factor for HAUTIs. Other risk factors for HAUTIs are the presence of immunosuppression and previous urinary tract infections.

In urological patients, Enterobacterales are the principal causative agent of HAUTIs, and E. coli is the most frequently isolated microorganism. However, there is also a high rate of microorganisms other than E. coli such as Klebsiella spp. and Enterococcus spp. Non-E. coli microorganisms show a higher prevalence in immunosuppressed patients and those with urinary catheters before admission. High resistance patterns are reported in patients with HAUTIs, and ESBL-producing bacteria are frequently described. Moreover, the isolation of multidrug-resistant microorganisms is more common in immunosuppressed patients, those with previous urinary tract infections, and urinary catheters into the upper urinary tract. Treatment must be tailored according to patient characteristics and patient profiles, bearing in mind the ORENUC classification for risk factors (no risk factors (O), recurrent urinary tract infections risk factors (R), extraurogenital risk factors (E), nephropathic disease (N), urological risk factors (U), permanent urinary catheter and non-resolvable urological risk factors (C)).

Evaluating the economic effects of genomic sequencing of pathogens to prioritise hospital patients competing for isolation beds

Objective This study compared the costs and patient movements of a new hospital protocol to discontinue contact precautions for patients with non-multiresistant methicillin-resistant Staphylococcus aureus (nmMRSA), based on whole-genome sequencing (WGS) of pathogens with current practice. Methods A hybrid simulation model was constructed and analysed over a 12-month time horizon. Six multidrug-resistant organisms and influenza were modelled concurrently where infected patients competed for isolation beds. Model inputs included pathogen incidence, resources for WGS, staff and contact precautions, hospital processes, room allocations and their associated costs. Data were sourced from aggregated records of patient admissions during 2017-18, clinical records and published reports. Results The WGS protocol resulted in 389 patients isolated (44% of current practice), 5223 'isolation bed days' (56%) and 268 closed-bed days (88%). Over 1 year, the mean (±s.d.) total cost for the WGS protocol was A$749243±126667; compared with current practice, the overall cost savings were A$690864±300464. Conclusion Using WGS to inform infection control teams of pathogen transmission averts patients from isolation rooms and reduces significant resources involved in implementing contact precautions. What is known about the topic? There are an estimated 265000 hospital-acquired infections (HAI) in Australia each year. WGS can accurately identify the genetic lineage among HAIs and determine transmission clusters that can help infection control staff manage patients. Economic appraisals are lacking to inform whether pathogen genomics services should be adopted within already-stretched hospital budgets. What does this paper add? An isolation protocol using pathogen genomics to provide additional information on the relatedness of a pathogen between colonised patients showed favourable results for healthcare costs and patient flow. Using WGS, in a confirmatory role, to discontinue certain patients from contact precautions and isolation rooms resulted in cost savings of A$690864 across 1 year for a single major hospital. What are the implications for practitioners? Using pathogen WGS services for infection control potentially curbs hospital spending, averts patient isolations and improves patient flow within hospitals.

Genomic and Chemical Investigation of Bioactive Secondary Metabolites From a Marine-Derived Fungus Penicillium steckii P2648

Marine fungi of the genus Penicillium are rich resources of secondary metabolites, showing a variety of biological activities. Our anti-bacterial screening revealed that the crude extract from a coral-derived fungus Penicillium steckii P2648 showed strong activity against some pathogenic bacteria. Genome sequencing and mining uncovered that there are 28 secondary metabolite gene clusters in P2648, potentially involved in the biosynthesis of antibacterial compounds. Chemical isolation and structural determination suggested citrinin is the dominant component of the crude extracts of P2648, and our further tests confirmed that citrinin showed excellent activities against various pathogenic bacteria. Moreover, the gene cluster containing a homolog of the polyketide synthase CitS was identified as the citrinin biosynthesis gene cluster through genetic analysis. Interestingly, three isoquinoline alkaloids were unexpectedly activated and isolated from the Δcits mutant and structural determination by using high-resolution electron spray ionization mass spectroscopy (HRESIMS), 1D, and 2D NMR. Further antibacterial assays displayed that compounds 1 and 2, but not compound 3, showed moderate activities against two antibiotic-resistant pathogenic bacteria with minimum inhibitory concentration (MIC) of 16–32 μg/ml. In conclusion, our results demonstrated that citrinin and isoquinoline alkaloids represent as the major antibacterial agents in the coral-associated fungus P. steckii P2648, and our genomic and chemical analyses present evidence in support of P. steckii P2648 as a potent natural products source for anti-bacterial drug discovery.

Clinical and Economic Impact of Community-Onset Urinary Tract Infections Caused by ESBL-Producing Klebsiella pneumoniae Requiring Hospitalization in Spain: An Observational Cohort Study

Objective: To analyze the clinical and economic impact of community-onset urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae requiring hospitalization. Methods: A retrospective cohort study that included all adults with a UTI caused by K. pneumoniae that were admitted to a tertiary care hospital in Barcelona, Spain, between 2011 and 2015. Demographic, clinical, and economic data were analyzed. Results: One hundred and seventy-three episodes of UTIs caused by K. pneumoniae were studied; 112 were non-ESBL-producing and 61 were ESBL-producing. Multivariate analysis identified ESBL production, acute confusional state associated with UTI, shock, and the time taken to obtain adequate treatment as risk factors for clinical failure during the first seven days. An economic analysis showed differences between ESBL-producing and non-ESBL-producing K. pneumoniae for the total cost of hospitalization per episode (mean EUR 6718 vs EUR 3688, respectively). Multivariate analysis of the higher costs of UTI episodes found statistically significant differences for ESBL production and the time taken to obtain adequate treatment. Conclusion: UTIs caused by ESBL-producing K. pneumoniae requiring hospitalization and the time taken to obtain adequate antimicrobial therapy are associated with worse clinical and economic outcomes.

Economic Burden of Urinary Tract Infections From Antibiotic-Resistant Escherichia coli Among Hospitalized Adult Patients in Lebanon: A Prospective Cohort Study

OBJECTIVES

The rising incidence of urinary tract infections (UTIs) attributable to Escherichia coli resistant isolates is becoming a serious public health concern. Although global rates of infection vary considerably by region, the growing prevalence of this uropathogen has been associated with a high economic burden and health strain. This study aims: (1) to estimate the differences in clinical and economic outcomes between 2 groups of adult hospitalized patients with UTIs from E. coli resistant and susceptible bacteria and (2) to investigate drivers of this cost from a payer's perspective.

METHODS

A prospective multicenter cohort study was conducted in 10 hospitals in Lebanon. The cost analysis followed a bottom-up microcosting approach; a linear regression was constructed to evaluate the predictors of hospitalization costs and a Cox proportional hazards model was used to estimate the impact of resistance on length of stay (LOS) and in-hospital mortality.

RESULTS

Out of 467 inpatients, 250 cases were because of resistant E. coli isolates. Results showed that patients with resistant uropathogens had 29% higher mean total hospitalization costs ($3429 vs $2651; P = .004), and an extended median LOS (6 days vs 5 days; P = .020) compared with susceptible cohorts. The selection of resistant bacteria and the Charlson comorbidity index predicted higher total hospitalization costs and in-hospital mortality.

CONCLUSION

In an era of increased pressure for cost containment, this study showed the burden of treating UTIs resulting from resistant bacteria. The results can inform cost-effectiveness analyses that intend to evaluate the benefit of a national action plan aimed at decreasing the impact of antibiotic resistance.

Pharmacodynamics of Ceftibuten: An Assessment of an Oral Cephalosporin against Enterobacterales in a Neutropenic Murine Thigh Model

Efforts to develop and pair novel oral β-lactamase inhibitors with existing β-lactam agents to treat extended spectrum β-lactamase (ESBL) and carbapenemase-producing Enterobacterales are gaining ground. Ceftibuten is an oral third-generation cephalosporin capable of achieving high urine concentrations; however, there are no robust data describing its pharmacodynamic profile. This study characterizes ceftibuten pharmacokinetics and pharmacodynamics in a neutropenic murine thigh infection model. Enterobacterales isolates expressing no known clinically-relevant enzymatic resistance (n = 7) or harboring an ESBL (n = 2) were evaluated. The ceftibuten minimum inhibitory concentrations (MICs) were 0.03–4 mg/L. Nine ceftibuten regimens, including a human-simulated regimen (HSR) equivalent to clinical ceftibuten doses of 300 mg taken orally every 8 h, were utilized to achieve various fT > MICs. A sigmoidal E_max model was fitted to fT > MIC vs. change in log₁₀ CFU/thigh to determine the requirements for net stasis and 1-log₁₀ CFU/thigh bacterial burden reduction. The growth of the 0 h and 24 h control groups was 5.97 ± 0.37 and 8.51 ± 0.84 log₁₀ CFU/thigh, respectively. Ceftibuten HSR resulted in a -0.49 to -1.43 log₁₀ CFU/thigh bacterial burden reduction at 24 h across the isolates. Stasis and 1-log₁₀ CFU/thigh reduction were achieved with a fT > MIC of 39% and 67%, respectively. The fT > MIC targets identified can be used to guide ceftibuten dosage selection to optimize the likelihood of clinical efficacy.

Economic Burden of Urinary Tract Infections From Antibiotic-Resistant Escherichia coli Among Hospitalized Adult Patients in Lebanon: A Prospective Cohort Study

OBJECTIVES

The rising incidence of urinary tract infections (UTIs) attributable to Escherichia coli resistant isolates is becoming a serious public health concern. Although global rates of infection vary considerably by region, the growing prevalence of this uropathogen has been associated with a high economic burden and health strain. This study aims: (1) to estimate the differences in clinical and economic outcomes between 2 groups of adult hospitalized patients with UTIs from E. coli resistant and susceptible bacteria and (2) to investigate drivers of this cost from a payer's perspective.

METHODS

A prospective multicenter cohort study was conducted in 10 hospitals in Lebanon. The cost analysis followed a bottom-up microcosting approach; a linear regression was constructed to evaluate the predictors of hospitalization costs and a Cox proportional hazards model was used to estimate the impact of resistance on length of stay (LOS) and in-hospital mortality.

RESULTS

Out of 467 inpatients, 250 cases were because of resistant E. coli isolates. Results showed that patients with resistant uropathogens had 29% higher mean total hospitalization costs ($3429 vs $2651; P = .004), and an extended median LOS (6 days vs 5 days; P = .020) compared with susceptible cohorts. The selection of resistant bacteria and the Charlson comorbidity index predicted higher total hospitalization costs and in-hospital mortality.

CONCLUSION

In an era of increased pressure for cost containment, this study showed the burden of treating UTIs resulting from resistant bacteria. The results can inform cost-effectiveness analyses that intend to evaluate the benefit of a national action plan aimed at decreasing the impact of antibiotic resistance.

Overview: The Ongoing Threat of Antimicrobial Resistance

The effectiveness of antibiotics continues to erode because of the relentless spread of antimicrobial resistance (AMR). Public and private foundations, professional organizations, and international health agencies recognize the threat posed by AMR and have issued calls for action. One of the main drivers of AMR is overprescription of antibiotics, both in human and in veterinary medicine. The One Health concept is a response from a broad group of stakeholders to counter the global health threat posed by AMR. In this article, we discuss current trends in AMR and suggest strategies to mitigate its ongoing dissemination.

Antimicrobial resistance and molecular detection of extended spectrum β-lactamase producing Escherichia coli isolates from raw meat in Greater Accra region, Ghana

BACKGROUND

Typically, raw meat can be contaminated with antibiotic resistant pathogens at unhygienic slaughter and sale points. Consumption of meat contaminated with antibiotic resistant E. coli is associated with grave health care consequences. The aim of this study was to determine the microbial quality of raw meat, the antimicrobial susceptibility and Extended Spectrum Beta Lactamase (ESBL) production in E. coli isolates from raw meat.

RESULTS

Total Plate Counts exceeded the acceptable limit of 5.0 log CFU/ cm² in 60.5% (124/205) of raw meat samples. Total Coliform Counts in 70.7% (145/205) of samples were in excess of the acceptable limit of 2.5 log CFU/cm². E. coli was detected in about half of raw meat samples (48%), ranging from 9.5-79.0% among the slaughter sites. Isolates were susceptible to meropenem (100%), ceftriaxone (99%), cefotaxime (98%), chloramphenicol (97%), gentamycin (97%), ciprofloxacin (92%) and amikacin (92%), but resistant to ampicillin (57%), tetracycline (45%), sulfamethoxazole-trimethoprim (21%) and cefuroxime (17%). Multi-drug resistance (MDR) was identified in 22% of the isolates. The bla_{TEM gene} was detected in 4% (4/98) of E. coli isolates in this study.

CONCLUSION

The levels of microbial contamination of raw meat in this study were unacceptable. Meat handlers and consumers are at risk of foodborne infections from E. coli including ESBL producing E. coli that are resistant to most antibiotics in use. We recommend an enhanced surveillance for antibiotic resistance in food products for the early detection of emerging resistant bacteria species in the food chain.

Quantifying risk of disease due to extended-spectrum β-lactamase producing Enterobacteriaceae in patients who are colonized at ICU admission

BACKGROUND

The prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) has globally increased and spread to the community. No clinical score is available to select carriers in whom these organisms can be empirically targeted at ICU admission.

METHODS

We prospectively assessed between 2009 and 2017 the prevalence of ESBL-PE infection in carriers at ICU admission. A logistic regression was used to determine independent risk factors associated with ESBL-PE infection, and to build a clinical risk score.

RESULTS

Of the 8,061 admissions over the study 7-year period, 745 (9%) patients were ESBL-PE carriers at admission, of whom 395 had infections at ICU admission including 59 (15%) who had culture-proven ESBL-PE related infection. By multivariable analysis, age >60 years, cirrhosis, being on broad-spectrum antibiotics within the past three months, urinary or intra-abdominal source of infection, and the absence of chronic pulmonary disease, were the five independent factors associated with ESBL-PE infection in carriers. A clinical risk score ranging from 0 to 7 was built based on these variables, with an area under the receiver operating characteristic curve (ROC) of 0.82 (95% CI 0.78-0.86); p <0.001. The prevalence of ESBL-PE infection for clinical risk scores of 0-1, 2-3, 4-5, or 6-7 was 0%, 4%, 26%, and 49%, respectively. The negative predictive value when Mondor ESBL risk score is <4 was 97%.

CONCLUSION

ESBL-PE related infection was not common in carriers at ICU admission. A clinical risk score may spare ESBL-PE carriers with lower risk of ESBL-PE infection at ICU admission unnecessary empiric carbapenem therapy.

Bacterial Profiles and Their Associated Factors of Urinary Tract Infection and Detection of Extended Spectrum Beta-Lactamase Producing Gram-Negative Uropathogens Among Patients with Diabetes Mellitus at Dessie Referral Hospital, Northeastern Ethiopia

PURPOSE

To determine the bacterial profile with its associated risk factors and to identify extended spectrum beta-lactamase producing Gram-negative bacterial uropathogens among diabetic patients at Dessie Referral Hospital, Northeastern Ethiopia.

MATERIALS AND METHODS

A hospital-based cross-sectional study was conducted from May to September 2018. A total of 336 diabetic patients were included using a simple random sampling technique. A structured questionnaire was used to collect socio-demographic and risk factor-related data. A 10-mL mid-stream urine specimen was collected and transported to the microbiology laboratory for culture, antimicrobial susceptibility testing, and detection of ESBL-producing bacteria. The data were entered into SPSS version 22, and descriptive statistics, bivariate and multivariate logistic regression analyses were performed. A p-value ≤0.05 with a 95% confidence interval was considered for statistical significance.

RESULTS

Among 336 diabetic patients, the overall prevalence of UTI was 11.6%. The predominant bacterial isolate was Escherichia coli 12/39 (30.8%), followed by Klebsiella pneumoniae 11/39 (28.2%) and coagulase-negative staphylococci 7/39 (17.9%). Gram-negative isolates showed 100% resistance to ampicillin, whereas Gram-positive isolates showed a high level of resistance to penicillin and tetracycline. Moreover, MDR was observed among 18 (46.2%) of the isolates and 2 of the isolated Gram-negative bacteria were ESBL producers. Being illiterate (AOR=7.226, 95% CI: (1.478, 35.340), p<0.015), having current symptoms of UTI (AOR = 2.702, 95% CI: (1.102, 6.624), p=0.030), and blood glucose level ≥126 mg/dl (AOR = 2.940, 95% CI: (1.080, 8.005), p=0.035) were significantly associated with the occurrence of bacterial UTI.

CONCLUSION

The overall prevalence of significant bacteriuria (11.6%) in this study was comparable with some studies in Ethiopia and relatively lower than others. A moderately higher rate of resistance to the commonly used antimicrobial agents was noticed for both Gram-negative and Gram-positive isolates. Health information dissemination should be given about UTI, glycemic control, and habit of drug use for diabetes mellitus patients.

Economic burden of antibiotic resistance in ESKAPE organisms: a systematic review

Background

Antibiotic resistance (ABR) is one of the biggest threats to global health. Infections by ESKAPE (Enterococcus, S. aureus, K. pneumoniae, A. baumannii, P. aeruginosa, and E. coli) organisms are the leading cause of healthcare-acquired infections worldwide. ABR in ESKAPE organisms is usually associated with significant higher morbidity, mortality, as well as economic burden. Directing attention towards the ESKAPE organisms can help us to better combat the wide challenge of ABR, especially multi-drug resistance (MDR).

Objective

This study aims to systematically review and evaluate the evidence of the economic consequences of ABR or MDR ESKAPE organisms compared with susceptible cases or control patients without infection/colonization in order to determine the impact of ABR on economic burden.

Methods

Both English-language databases and Chinese-language databases up to 16 January, 2019 were searched to identify relevant studies assessing the economic burden of ABR. Studies reported hospital costs (charges) or antibiotic cost during the entire hospitalization and during the period before/after culture among patients with ABR or MDR ESKAPE organisms were included. The costs were converted into 2015 United States Dollars. Disagreements were resolved by a third reviewer.

Results

Of 13,693 studies identified, 83 eligible studies were included in our review. The most studied organism was S. aureus, followed by Enterococcus, A. baumannii, E. coli, E. coli or/and K. pneumoniae, P. aeruginosa, and K. pneumoniae. There were 71 studies on total hospital cost or charge, 12 on antibiotic cost, 11 on hospital cost or charge after culture, 4 on ICU cost, 2 on hospital cost or charge before culture, and 2 on total direct and indirect cost. In general, ABR or MDR ESKAPE organisms are significantly associated with higher economic burden than those with susceptible organisms or those without infection or colonization. Nonetheless, there were no differences in a few studies between the two groups on total hospital cost or charge (16 studies), antibiotic cost (one study), hospital cost before culture (one study), hospital cost after culture (one study). Even, one reported that costs associated with MSSA infection were higher than the costs for similar MRSA cases.

Conclusions

ABR in ESKAPE organisms is not always, but usually, associated with significantly higher economic burden. The results without significant differences may lack statistical power to detect a significant association. In addition, study design which controls for severity of illness and same empirical antibiotic therapy in the two groups would be expected to bias the study towards a similar, even negative result. The review also highlights key areas where further research is needed.

Direct medical costs of urinary tract infections by Gram-negative bacilli resistant to beta-lactams in a tertiary care hospital in Medellín, Colombia

Introduction: Urinary tract infections are very frequent in the hospital environment and given the emergence of antimicrobial resistance, they have made care processes more complex and have placed additional pressure on available healthcare resources. Objective: To describe and compare excess direct medical costs of urinary tract infections due to Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa resistant to beta-lactams. Materials and methods: A cohort study was conducted in a third level hospital in Medellín, Colombia, from October, 2014, to September, 2015. It included patients with urinary tract infections caused by beta-lactam-susceptible bacteria, third and fourth generation cephalosporin-resistant, as well as carbapenem-resistant. Costs were analyzed from the perspective of the health system. Clinical-epidemiological information was obtained from medical records and the costs were calculated using standard tariff manuals. Excess costs were estimated with multivariate analyses. Results: We included 141 patients: 55 (39%) were sensitive to beta-lactams, 54 (38.3%) were resistant to cephalosporins and 32 (22.7%) to carbapenems. The excess total adjusted costs of patients with urinary tract infections due to cephalosporin- and carbapenem-resistant bacteria were US$ 193 (95% confidence interval (CI): US$ -347-734) and US$ 633 (95% CI: US$ -50-1316), respectively, compared to the group of patients with beta-lactam sensitive urinary tract infections. The differences were mainly found in the use of broad-spectrum antibiotics such as meropenem, colistin, and fosfomycin. Conclusion: Our results show a substantial increase in the direct medical costs of patients with urinary tract infections caused by beta-lactam-resistant Gram-negative bacilli (cephalosporins and carbapenems). This situation is of particular concern in endemic countries such as Colombia, where the high frequencies of urinary tract infections and the resistance to beta-lactam antibiotics can generate a greater economic impact on the health sector.

Monitoring healthcare-associated infections and antimicrobial use at regional level through repeated point prevalence surveys: what can be learnt?

BACKGROUND

Healthcare-associated infections (HAIs) surveillance is an essential part of any infection prevention and control programme. Repeated point prevalence surveys (PPSs) according to European Centre for Disease Prevention and Control (ECDC) protocol have been implemented in all Friuli Venezia Giulia (FVG) region (Italy) acute hospitals to reduce and control HAIs.

AIM

Using the repeated PPSs within a regional-healthcare system (RHS) to promote and evaluate infection prevention and control (IPC) programmes.

METHODS

The standard versions of the ECDC PPS protocols were used in all four surveys (2011, 2013, 2015, 2017). All RHS public and private accredited hospitals were involved within the 'safe care network' programme.

FINDINGS

The numbers of surveyed patients in the four PPSs were 3172, 3253, 2969 and 3036, respectively. Prevalence of HAIs and antimicrobial use (AU) decreased significantly from 2011: HAIs (P<0.05) 7.1%, 6.3%, 5.5%, 5.8% and AU (P<0.01) 40.4%, 39.2%, 36.0%, 37.2%, respectively. The appropriateness of duration of surgical prophylaxis increased significantly (<24 h increased through surveys related to one in 2011: odds ratio (OR), 95% confidence interval (CI) 1.29, 0.92-1.81; 1.95, 1.31-2.91; 1.78, 1.20-2.64, respectively). The most frequently detected HAIs were: bloodstream, urinary tract, pneumonia and surgical site (more than the 70% of HAIs in each PPS).

CONCLUSION

The FVG regional approach to HAIs and AU surveillance was able to contribute to reduce prevalence over a 7-year period. Furthermore, it was able to keep hospital attention on HAIs and AU through the years and to guarantee a standardized and comparable evaluation of HAIs and AU burden in all RHS hospitals, as well as impacting on HAIs and AU regional programmes.

Disparity of the "screen-and-isolate" policy for multidrug-resistant organisms: A national survey in French adult ICUs

BACKGROUND

The prevalence of multidrug-resistant organisms (MDROs) has dramatically increased. The aim of this survey was to describe and analyze the different screening and isolation policies regarding MDROs in French adult intensive care units (ICUs).

MATERIALS AND METHODS

A multicenter online survey was performed among French ICUs, including 63 questions distributed into 4 parts: characteristics of the unit, MDRO screening policy, policy regarding contact precautions, and ecology of the unit.

RESULTS

From April 2015 to June 2016, 73 of 301 ICUs (24%) participated in the survey. MDRO screening was performed on admission in 96% of ICUs, for at least 1 MDRO (78%). MDRO screening was performed weekly during ICU stay in 83% of ICUs. Preemptive isolation was initiated on admission in 82% of ICUs, mostly in a targeted way (71%). Imported and acquired MDRO rates >10% were reported in 44% and 27% of ICUs, respectively. An MDRO outbreak had occurred within the past 3 years in 48% of cases.

CONCLUSION

French ICUs have variable screening and isolation approaches for MDROs, as up to 10 combinations were met. Discrepancies with the 2009 national guidelines were observed. Very few ICUs practice without some form of screening and isolation of patients upon admission.

Factors associated with bacteraemia due to multidrug-resistant organisms among bacteraemic patients with multidrug-resistant organism carriage: a case control study

Background

Infections caused by multidrug-resistant organisms (MDRO) are emerging worldwide. Physicians are increasingly faced with the question of whether patients need empiric antibiotic treatment covering these pathogens. This question is especially essential among MDRO carriers. We aim to determine the occurrence of MDRO bacteraemia among bacteraemic patients colonized with MDRO, and the associated factors with MDRO bacteraemia among this population.

Methods

We performed a retrospective monocentric study among MDRO carriers hospitalized with bacteraemia between January 2013 and August 2016 in a French hospital. We compared characteristics of patients with MDRO and non-MDRO bacteraemia.

Results

Overall, 368 episodes of bacteraemia were reviewed; 98/368 (26.6%) occurred among MDRO carriers.

Main colonizing bacteria were extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (40/98; 40.8%), ESBL-producing Klebsiella pneumoniae (35/98; 35.7%); methicillin-resistant Staphylococcus aureus (26/98; 26.5%) and multidrug-resistant Pseudomonas aeruginosa (PA) (12/98; 12.2%).

There was no significant difference considering population with MDRO bacteraemia vs. non-MDRO bacteraemia, except for immunosuppression [OR 2.86; p = 0.0207], severity of the episode [OR 3.13; p = 0.0232], carriage of PA [OR 5.24; p = 0.0395], and hospital-acquired infection [OR 2.49; p = 0.034].

In the multivariate analysis, factors significantly associated with MDRO bacteraemia among colonized patient were only immunosuppression [OR = 2.96; p = 0.0354] and the hospital-acquired origin of bacteraemia [OR = 2.62; p = 0.0427].

Conclusions

According to our study, occurrence of bacteraemia due to MDRO among MDRO carriers was high. Factors associated with MDRO bacteraemia were severity of the episode and hospital-acquired origin of the bacteraemia. Thus, during bacteraemia among patients colonized with MDRO, if such characteristics are present, broad-spectrum antimicrobial treatment is recommended.

Risk factors for community-acquired Escherichia coli bacteraemia: a systematic review protocol

Introduction: Rates of community-acquired Escherichia coli bacteraemia (ECB) have been consistently rising. As rates of antimicrobial resistance (AMR), particularly in Gram-negative bacteria, are also increasing, this is of concern both for management of individual patients and healthcare systems. There is currently little data on the risk factors for development of community-acquired ECB: this review aims to identify these risk factors in order to inform community interventions to reduce ECB as well as antibiotic prescribing policy.

Methods and analysis: We will search Medline (Ovid), Embase (Ovid), Web of Science/Scopus and the Cochrane Central Register of Controlled Trials for published reports on observational and experimental primary research studies involving patients admitted to hospital with community-acquired ECB. Two reviewers will independently screen the studies for eligibility, perform data collection and assess study quality and risk of bias. Random effects meta-analyses will be performed if appropriate.

Ethics and dissemination: No primary data will be collected for this study and so formal ethical approval is not required. We will publish the results of our review in relevant peer-reviewed medical journals, and will also seek to present them at relevant medical conferences.

PROSPERO registration number:CRD42018104402

Treatment of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBLs) infections: what have we learned until now?

The spread of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-PE) has dramatically increased worldwide, and this “evolving crisis” is currently regarded as one of the most important public health threats. The growing problem of ESBL-PE antimicrobial resistance seems to have a dual face between “Scylla and Charybdis”: on one hand the potential for rapid spread and dissemination of resistance mechanisms and on the other hand the injudicious overuse of antimicrobial agents and the inadequate infection control measures, especially in the health-care setting. Given the World Health Organization’s warning against a “post antibiotic era”, health-care providers are at a critical standpoint to find a “balance” between safe and effective ESBL-PE treatment and avoidance of inducing further resistance mechanisms. The aim of the review is to summarize the updated published knowledge in an attempt to answer basic everyday clinical questions on how to proceed to effective and the best ESBL-PE treatment options based on the existing published data.

The Role of Cefepime in the Treatment of Extended-Spectrum Beta-Lactamase Infections

OBJECTIVE

To review the efficacy of cefepime for use in infections caused by extended-spectrum beta-lactamase (ESBL)-producing organisms.

DATA SOURCES

A PubMed literature search (May 2000 to June 2017) was performed using the keyword cefepime and the MeSH terms beta-lactamases, cephalosporinases, and Enterobacteriaceae infections.

STUDY SELECTION AND DATA EXTRACTION

All human, English language studies evaluating cefepime use for the treatment of ESBL-producing Escherichia coli and Klebsiella pneumoniae infections were included.

DATA SYNTHESIS

Studies assessing the use of cefepime for ESBL infections are few, and clinical studies are limited by design and sample size. The largest pharmacokinetic/pharmacodynamic study, a Monte Carlo simulation using data from the U.S. SENTRY antimicrobial surveillance program, evaluating cefepime use for infections due to ESBL-producing organisms found a 95% to 100% probability of target attainment with traditional cefepime dosing regimens. Most clinical studies found that patients treated with cefepime empirically and definitively had higher rates of mortality than those treated with carbapenems. However, in concordance with other studies reporting minimum inhibitory concentration (MIC) data, lower MICs were associated with lower mortality.

CONCLUSIONS

Cefepime should be avoided for empiric treatment of suspected ESBL infections and should only be considered for definitive treatment if the MIC ≤1 µg/mL. However, the site and severity of infection, local resistance patterns, and patient-specific risk factors should also help guide antimicrobial selection.

Universal or targeted approach to prevent the transmission of extended-spectrum beta-lactamase-producing Enterobacteriaceae in intensive care units: a cost-effectiveness analysis

OBJECTIVE

Several control strategies have been used to limit the transmission of multidrug-resistant organisms in hospitals. However, their implementation is expensive and effectiveness of interventions for the control of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) spread is controversial. Here, we aim to assess the cost-effectiveness of hospital-based strategies to prevent ESBL-PE transmission and infections.

DESIGN

Cost-effectiveness analysis based on dynamic, stochastic transmission model over a 1-year time horizon.

PATIENTS AND SETTING

Patients hospitalised in a hypothetical 10-bed intensive care unit (ICU) in a high-income country.

INTERVENTIONS

Base case scenario compared with (1) universal strategies (eg, improvement of hand hygiene (HH) among healthcare workers, antibiotic stewardship), (2) targeted strategies (eg, screening of patient for ESBL-PE at ICU admission and contact precautions or cohorting of carriers) and (3) mixed strategies (eg, targeted approaches combined with antibiotic stewardship).

MAIN OUTCOMES AND MEASURES

Cases of ESBL-PE transmission, infections, cost of intervention, cost of infections, incremental cost per infection avoided.

RESULTS

In the base case scenario, 15 transmissions and five infections due to ESBL-PE occurred per 100 ICU admissions, representing a mean cost of €94 792. All control strategies improved health outcomes and reduced costs associated with ESBL-PE infections. The overall costs (cost of intervention and infections) were the lowest for HH compliance improvement from 55%/60% before/after contact with a patient to 80%/80%.

CONCLUSIONS

Improved compliance with HH was the most cost-saving strategy to prevent the transmission of ESBL-PE. Antibiotic stewardship was not cost-effective. However, adding antibiotic restriction strategy to HH or screening and cohorting strategies slightly improved their effectiveness and may be worthy of consideration by decision-makers.

Milk microbiome and bacterial load following dry cow therapy without antibiotics in dairy cows with healthy mammary gland

Preventive infusion of antibiotics in the mammary gland of cows consumes 11 tons/year of medically relevant antimicrobials, yet, this practice might not be critical to prevent new infections in the healthy mammary gland of cows. Here, we used next-generation sequencing and quantitative real-time PCR to determine the impact of dry cow therapy without antibiotics on milk microbiome and bacterial load, respectively. Cows diagnosed as negative for mastitis at dry off were randomly allocated to receive antibiotic (intramammary ceftiofur hydrochloride) and teat sealant or just teat sealant. Firmicutes was the most abundant phylum, and Corynebacterium, Acinetobacter, and Staphylococcus, often involved in mastitis cases, were the most abundant genera across treatments and time. However, there were no effects of antimicrobial on milk microbiome and bacterial load. Bacterial load was greater at seven days postpartum than at dry off. Dry cow therapy based on teat sealant without antibiotics can be used with no detrimental impacts on milk microbiome and bacterial load in cows with a healthy mammary gland.

Overview: Global and Local Impact of Antibiotic Resistance

The rapid and ongoing spread of antibiotic resistance poses a serious threat to global public health. The indiscriminant use of antibiotics in agriculture and human medicine along with increasingly connected societies has fueled the distribution of antibiotic-resistant bacteria. These factors together have led to rising numbers of infections caused by multidrug-resistant and pan-resistant bacteria, with increases in morbidity and mortality. This article summarizes the trends in antibiotic resistance, discusses the impact of antibiotic resistance on society, and reviews the use of antibiotics in agriculture. Feasible ways to tackle antibiotic resistance to avert a post-antibiotic era are suggested.

Universal versus targeted additional contact precautions for multidrug-resistant organism carriage for patients admitted to an intensive care unit

BACKGROUND

Although additional contact precautions (ACPs) are routinely used to reduce cross-transmission of multidrug-resistant organisms (MDROs), the relevance of isolation precautions remains debated. We hypothesized that the collection of recognized risk factors for MDRO carriage on intensive care unit (ICU) admission might be helpful to target ACPs without increasing MDRO acquisition during ICU stays, compared with universal ACPs.

MATERIALS AND METHODS

This is a sequential single-center observational study performed in consecutive patients admitted to a French medical and surgical ICU. During the first 6-month period, screening for MDRO carriage and ACPs were performed in all patients. During the second 6-month period, screening was maintained, but ACP use was guided by the presence of at least 1 defined risk factor for MDRO.

RESULTS

During both periods, 33 (10%) and 30 (10%) among 327 and 297 admissions were, respectively, associated with a positive admission MDRO carriage. During both periods, a second screening was performed in 147 (45%) and 127 (43%) patients. Altogether, the rate of acquired MDRO (positive screening or clinical specimen) was similar during both periods (10% [n = 15] and 11.8% [n = 15], respectively; P = .66).

CONCLUSIONS

The results of our study contribute to support the safety of an isolation-targeted screening policy on ICU admission compared with universal screening and isolation regarding the rate of ICU-acquired MDRO colonization or infection.

Frequency, associated factors and outcome of multi-drug-resistant intensive care unit-acquired pneumonia among patients colonized with extended-spectrum β-lactamase-producing Enterobacteriaceae

Background

We assessed prevalence, associated factors and prognosis of extended-spectrum beta-lactamase-producing Enterobacteriaceae pneumonia acquired in intensive care unit (ESBL-PE pneumonia) among carriers. Variables associated with nosocomial pneumonia caused by carbapenem-resistant bacteria (CRB) were also assessed.

Methods

A 6-year prospective study (May 2009–March 2015) in the medical ICU of an 850-bed university-affiliated hospital was conducted.

Results

Of the 6303 patients admitted, 843 (13.4%) had ESBL-PE carriage detected. Among carriers, 111 (13%) patients developed ICU-acquired pneumonia of whom 48 (43%) had ESBL-PE pneumonia (6% of carriers). By multivariable analysis, SAPS II at admission >43 [OR 2.81 (1.16–6.79)] and colonization with Enterobacter sp. or K. pneumoniae species [OR 10.96 (2.93–41.0)] were independent predictive factors for ESBL-PE pneumonia in colonized patients, whereas receipt of >2 days of amoxicillin/clavulanic acid during the ICU stay [OR 0.24 (0.08–0.71)] was protective. Patients with ESBL-PE pneumonia had a higher SOFA score (p = 0.037) and more frequent septic shock at pneumonia onset (p = 0.047). However, ESBL-PE pneumonia was not an independent predictor of mortality. Twenty-five patients had pneumonia caused by CRB. Chronic renal insufficiency, administration of third-generation cephalosporin within the past 3 months, acute respiratory distress syndrome before pneumonia and prior therapy with a carbapenem or fluoroquinolones were associated with CRB pneumonia in this selected population.

Conclusions

Although few ESBL-PE carriers developed ESBL-PE pneumonia overall, a high proportion of pneumonia were caused by ESBL-PE in carriers developing ICUAP. ESBL-PE pneumonia was not an independent predictor of mortality. As pneumonia caused by CRB is increasing, knowledge of factors associated with ESBL-PE or CRB pneumonia may help empiric therapy of pneumonia among ESBL-PE carriers.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-017-0283-4) contains supplementary material, which is available to authorized users.

Increased Costs Associated with Bloodstream Infections Caused by Multidrug-Resistant Gram-Negative Bacteria Are Due Primarily to Patients with Hospital-Acquired Infections

The clinical and economic impacts of bloodstream infections (BSI) due to multidrug-resistant (MDR) Gram-negative bacteria are incompletely understood. From 2009 to 2015, all adult inpatients with Gram-negative BSI at our institution were prospectively enrolled. MDR status was defined as resistance to ≥3 antibiotic classes. Clinical outcomes and inpatient costs associated with the MDR phenotype were identified. Among 891 unique patients with Gram-negative BSI, 292 (33%) were infected with MDR bacteria. In an adjusted analysis, only history of Gram-negative infection was associated with MDR BSI versus non-MDR BSI (odds ratio, 1.60; 95% confidence interval [CI], 1.19 to 2.16; P = 0.002). Patients with MDR BSI had increased BSI recurrence (1.7% [5/292] versus 0.2% [1/599]; P = 0.02) and longer hospital stay (median, 10.0 versus 8.0 days; P = 0.0005). Unadjusted rates of in-hospital mortality did not significantly differ between MDR (26.4% [77/292]) and non-MDR (21.7% [130/599]) groups (P = 0.12). Unadjusted mean costs were 1.62 times higher in MDR than in non-MDR BSI ($59,266 versus $36,452; P = 0.003). This finding persisted after adjustment for patient factors and appropriate empirical antibiotic therapy (means ratio, 1.18; 95% CI, 1.03 to 1.36; P = 0.01). Adjusted analysis of patient subpopulations revealed that the increased cost of MDR BSI occurred primarily among patients with hospital-acquired infections (MDR means ratio, 1.41; 95% CI, 1.10 to 1.82; P = 0.008). MDR Gram-negative BSI are associated with recurrent BSI, longer hospital stays, and increased mean inpatient costs. MDR BSI in patients with hospital-acquired infections primarily account for the increased cost.

Healthcare costs doubled when children had urinary tract infections caused by extended-spectrum β-lactamase-producing bacteria

AIM

The impact of the emergence of antimicrobial resistant organisms has rarely been studied in children, including the healthcare costs of urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing bacteria. We evaluated the effect of ESBL on UTI healthcare costs and risk factors for paediatric UTIs.

METHODS

This retrospective case-control study covered 2005-2014 and focused on children below 16 years of age treated in a University hospital: 22 children with UTIs caused by ESBL-producing bacteria and 56 ESBL-negative UTI controls.

RESULTS

The median healthcare costs were 3929 Euros for the 22 ESBL patients and 1705 Euros for the 56 controls (p = 0.015). The mean and standard deviation length of hospital stay was 7.4 (5.9) days for the ESBL group and 3.6 (2.3) days for the controls (p = 0.007), and the figures for antibiotic treatment were 12.3 (5.5) days versus 5.8 (3.0) days (p < 0.001), respectively. The odd ratios for ESBL were underlying disease (6.63, p = 0.013), previous hospitalisation (6.07, p = 0.009) and antibiotic prophylaxis (5.20, p = 0.035).

CONCLUSION

Healthcare costs more than doubled when children had ESBL-related UTIs, mainly due to their increased length of stay. Effective oral antibiotics are urgently needed to treat paediatric infections caused by ESBL-producing bacteria.

Prospective study analyzing risk factors and characteristics of healthcare-associated infections in a Urology ward

PURPOSE

Healthcare-associated infections (HAIs) in urological patients have special features due to specific risk factors. Our objective was to evaluate the characteristics and risk factors for HAIs in patients hospitalized in a Urology ward.

MATERIALS AND METHODS

We evaluated prospectively, from 2012 to 2015, the incidence, types and risk factor for HAIs, microbiological and resistance patterns.

RESULTS

The incidence of HAIs was 6.3%. The most common types were urinary infections (70.5%) and surgical site infections (22.1%). Univariate analysis showed an increased risk of HAIs among patients with American Society of Anesthesiologists physical status classification system III-IV (odds ratio [OR], 1.39; p<0.001), immunosuppression (OR, 1.80; p=0.013), previous urinary infection (OR, 4.46; p<0,001), and urinary catheter before admission (OR, 1.74; p<0.001). The surgical procedures with the highest incidence of HAIs were radical cystectomy (54.2%) and renal surgery (8.7%). The most frequently isolated microorganisms were Escherichia coli (25.1%), Enterococcus spp. (17.5%), Klebsiella spp. (13.5%) and Pseudomonas aeruginosa (12.3%). Enterococcus sp was the most common microorganism after radical cystectomy and in surgical site infections, E. coli showed resistance rates of 53.5% for fluoroquinolones, 9.3% for amikacin. The percentage of extended-spectrum betalactamase producing E. coli was 24.7%. Klebsiella spp. showed resistance rates of 47.8% for fluoroquinolones, 7.1% for amikacin and 4.3% for carbapenems. Enterococcus spp showed resistance rates of 1.7% for vancomycin and; P. aeruginosa of 33.3% for carbapenems and 26.2% for amikacin.

CONCLUSIONS

Comorbidities, previous urinary infections, and urinary catheter are risk factors for HAIs. The microorganisms most commonly isolated were E. coli, Enterococcus and P. aeruginosa. Prospective monitoring may decrease the incidence of infections.

Clinical research in febrile neutropenia in cancer patients: Past achievements and perspectives for the future

Febrile neutropenia (FN) is responsible for significant morbidity and mortality. It can also be the reason for delaying or changing potentially effective treatments and generates substantial costs. It has been recognized for more than 50 years that empirical administration of broad spectrum antibiotics to patients with FN was associated with much improved outcomes; that has become a paradigm of management. Increase in the incidence of microorganisms resistant to many antibiotics represents a challenge for the empirical antimicrobial treatment and is a reason why antibiotics should not be used for the prevention of neutropenia. Prevention of neutropenia is best performed with the use of granulocyte colony-stimulating factors (G-CSFs). Prophylactic administration of G-CSFs significantly reduces the risk of developing FN and consequently the complications linked to that condition; moreover, the administration of G-CSF is associated with few complications, most of which are not severe. The most common reason for not using G-CSF as a prophylaxis of FN is the relatively high cost. If FN occurs, in spite of prophylaxis, empirical therapy with broad spectrum antibiotics is mandatory. However it should be adjusted to the risk of complications as established by reliable predictive instruments such as the Multinational Association for Supportive Care in Cancer. Patients predicted at a low level of risk of serious complications, can generally be treated with orally administered antibiotics and as out-patients. Patients with a high risk of complications should be hospitalized and treated intravenously. A short period of time between the onset of FN and beginning of empirical therapy is crucial in those patients. Persisting fever in spite of antimicrobial therapy in neutropenic patients requires a special diagnostic attention, since invasive fungal infection is a possible cause for it and might require the use of empirical antifungal therapy.

Intestinal Carriage of Carbapenemase-Producing Organisms: Current Status of Surveillance Methods

Carbapenemases have become a significant mechanism for broad-spectrum β-lactam resistance in Enterobacteriaceae and other Gram-negative bacteria such as Pseudomonas and Acinetobacter spp. Intestinal carriage of carbapenemase-producing organisms (CPOs) is an important source of transmission. Isolation of carriers is one strategy that can be used to limit the spread of these bacteria. In this review, we critically examine the clinical performance, advantages, and disadvantages of methods available for the detection of intestinal carriage of CPOs. Culture-based methods (Centers for Disease Control and Prevention [CDC] protocols, chromogenic media, specialized agars, and double-disk synergy tests) for detecting carriage of CPOs are convenient due to their ready availability and low cost, but their limited sensitivity and long turnaround time may not always be optimal for infection control practices. Contemporary nucleic acid amplification techniques (NAATs) such as real-time PCR, hybridization assays, loop-mediated isothermal amplification (LAMP), or a combined culture and NAAT approach may provide fast results and/or added sensitivity and specificity compared with culture-based methods. Infection control practitioners and clinical microbiologists should be aware of the strengths and limitations of available methods to determine the most suitable approach for their medical facility to fit their infection control needs.

Management of severe head injury with brain exposure in three loggerhead sea turtles Caretta caretta

The loggerhead Caretta caretta is the most common sea turtle in the Mediterranean. Currently, sea turtles are considered endangered, mainly due to the impact of human activities. Among traumatic lesions, those involving the skull, if complicated by brain exposure, are often life-threatening. In these cases, death could be the outcome of direct trauma of the cerebral tissue or of secondary meningoencephalitis. This uncontrolled study aims to evaluate the use of a plant-derived dressing (1 Primary Wound Dressing®) in 3 sea turtles with severe lesions of the skull exposing the brain. Following surgical curettage, the treatment protocol involved exclusive use of the plant-derived dressing applied on the wound surface as the primary dressing, daily for the first month and then every other day until the end of treatment. The wound and peri-wound skin were covered with a simple secondary dressing without any active compound (non-woven gauze with petroleum jelly). Data presented herein show an excellent healing process in all 3 cases and no side effects due to contact of the medication with the cerebral tissue.

Infections caused by extended-spectrum beta-lactamases producing Enterobacteriaceae: clinical and economic impact in patients hospitalized in 2 teaching hospitals in Dakar, Senegal

BACKGROUND

Infections caused by extended-spectrum beta-lactamases producing Enterobacteriaceae (ESBL-E) are of major concern in clinical practice because of limited therapeutic options effective to treat them. Published studies showed that ESBL-E, widely spread in Europe, United States or Asia; are also frequent in Africa. However, the impact of ESBL-E infections is yet to be adequately determined in Sub-Saharan African countries, particularly in Senegal. The aim of our study was to estimate the incidence rate of ESBL-E infections and to assess their clinical and economic impact in Senegal.

METHODS

Two retrospective cohort studies were conducted in patients hospitalized from April to October 2012. A classic retrospective cohort study comparing patients infected by an Enterobacteriaceae producer of ESBL (ESBL+) and patients infected by an Enterobacteriaceae non-producer of ESBL (ESBL-) was carried out for fatal outcomes. Besides, a retrospective parallel cohort study comparing infected patients by an ESBL+ and ESBL- versus uninfected patients was carried out for the excess LOS analyses. Multivariable regression analysis was performed to identify risk factors for fatal outcomes. A multistate model and a cost-of-illness analysis were used to estimate respectively the excess length of stay (LOS) attributable to ESBL production and costs associated. Cox proportional hazards models were used to assess the independent effect of ESBL+ and ESBL- infections on LOS.

RESULTS

The incidence rate of ESBL-E infections was 3 cases/1000 patient-days (95 % CI: 2.4-3.5 cases/1000 patient-days). Case fatality rate was higher in ESBL+ than in ESBL- infections (47.3 % versus 22.4 %, p = 0.0006). Multivariable analysis indicated that risk factors for fatal outcomes were the production of ESBL (OR = 5.7, 95 % CI: 3.2-29.6, p = 0.015) or being under mechanical ventilation (OR = 5.6, 95 % CI: 2.9-57.5, p = 0.030). Newborns and patients suffering from meningitidis or cancer were patients at-risk for fatal outcomes. ESBL production increased hospital LOS (+4 days) and reduced significantly the hazard of discharge after controlling for confounders (HR = 0.3, 95 % CI:0.2-0.4). The additional cost associated with ESBL-production of €100 is substantial given the lower-middle-income status of Senegal.

CONCLUSION

Our findings show an important clinical and economic impact of ESBL-E infections in Senegal and emphasize the need to implement adequate infection control measures to reduce their incidence rate. An antibiotic stewardship program is also crucial to preserve the effectiveness of our last-resort antibiotic drugs.

Cost Attributable to Nosocomial Bacteremia. Analysis According to Microorganism and Antimicrobial Sensitivity in a University Hospital in Barcelona

AIM

To calculate the incremental cost of nosocomial bacteremia caused by the most common organisms, classified by their antimicrobial susceptibility.

METHODS

We selected patients who developed nosocomial bacteremia caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa. These microorganisms were analyzed because of their high prevalence and they frequently present multidrug resistance. A control group consisted of patients classified within the same all-patient refined-diagnosis related group without bacteremia. Our hospital has an established cost accounting system (full-costing) that uses activity-based criteria to analyze cost distribution. A logistic regression model was fitted to estimate the probability of developing bacteremia for each admission (propensity score) and was used for propensity score matching adjustment. Subsequently, the propensity score was included in an econometric model to adjust the incremental cost of patients who developed bacteremia, as well as differences in this cost, depending on whether the microorganism was multidrug-resistant or multidrug-sensitive.

RESULTS

A total of 571 admissions with bacteremia matched the inclusion criteria and 82,022 were included in the control group. The mean cost was € 25,891 for admissions with bacteremia and € 6,750 for those without bacteremia. The mean incremental cost was estimated at € 15,151 (CI, € 11,570 to € 18,733). Multidrug-resistant P. aeruginosa bacteremia had the highest mean incremental cost, € 44,709 (CI, € 34,559 to € 54,859). Antimicrobial-susceptible E. coli nosocomial bacteremia had the lowest mean incremental cost, € 10,481 (CI, € 8,752 to € 12,210). Despite their lower cost, episodes of antimicrobial-susceptible E. coli nosocomial bacteremia had a major impact due to their high frequency.

CONCLUSIONS

Adjustment of hospital cost according to the organism causing bacteremia and antibiotic sensitivity could improve prevention strategies and allow their prioritization according to their overall impact and costs. Infection reduction is a strategy to reduce resistance.

Unique Risks and Clinical Outcomes Associated With Extended-Spectrum β-Lactamase Enterobacteriaceae in Veterans With Spinal Cord Injury or Disorder: A Case-Case-Control Study

OBJECTIVES To describe the burden of extended-spectrum β-lactamase (ESBL) Enterobacteriaceae in veterans with spinal cord injury or disorder (SCI/D), to identify risk factors for ESBL acquisition, and to assess impact on clinical outcomes DESIGN Retrospective case-case-control study PATIENTS AND SETTING Veterans with SCI/D and utilization at a Veterans' Affairs medical center from January 1, 2012, to December 31, 2013. METHODS Patients with a positive culture for ESBL Klebsiella pneumoniae, Escherichia coli, or Proteus mirabilis were matched with patients with non-ESBL organisms by organism, facility, and level of care and to uninfected controls by facility and level of care. Inpatients were also matched by time at risk. Univariate and multivariate matched models were assessed for differences in risk factors and outcomes. RESULTS A total of 492 cases (62.6% outpatients) were matched 1:1 with each comparison group. Recent prior use of fluoroquinolones and prior use of third- and fourth-generation cephalosporins were independently associated with ESBL compared to the non-ESBL group (adjusted odds ratio [aOR], 2.61; 95% confidence interval [CI], 1.77-3.84; P<.001 for fluoroquinolones and aOR, 3.86; 95% CI, 2.06-7.25; P<.001 for third- and fourth-generation cephalosporins) and the control group (aOR, 2.10; 95% CI, 1.29-3.43; P = .003 for fluoroquinolones; and aOR, 3.31; 95% CI, 1.56-7.06; P=.002 for third- and fourth-generation cephalosporins). Although there were no differences in mortality rate, the ESBL group had a longer post-culture length of stay (LOS) than the non-ESBL group (incidence rate ratio, 1.36; 95% CI, 1.13-1.63; P=.001). CONCLUSIONS All SCI/D patients with ESBL were more likely to have had recent exposure to fluoroquinolones or third- and fourth-generation cephalosporins, and hospitalized patients were more likely to have increased post-culture LOS. Programs targeted toward reduced antibiotic use in SCI/D patients may prevent subsequent ESBL acquisition. Infect Control Hosp Epidemiol 2016;37:768-776.

Epidemiology and Burden of Bloodstream Infections Caused by Extended-Spectrum Beta-Lactamase Producing Enterobacteriaceae in a Pediatric Hospital in Senegal

Context

Severe bacterial infections are not considered as a leading cause of death in young children in sub-Saharan Africa. The worldwide emergence of extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) could change the paradigm, especially in neonates who are at high risk of developing healthcare-associated infections.

Objective

To evaluate the epidemiology and the burden of ESBL-E bloodstream infections (BSI).

Methods

A case-case-control study was conducted in patients admitted in a pediatric hospital during two consecutive years. Cases were patients with Enterobacteriaceae BSI and included ESBL-positive (cases 1) and ESBL-negative BSI (cases 2). Controls were patients with no BSI. Multivariate analysis using a stepwise logistic regression was performed to identify risk factors for ESBL acquisition and for fatal outcomes. A multistate model was used to estimate the excess length of hospital stay (LOS) attributable to ESBL production while accounting for time of infection. Cox proportional hazards models were performed to assess the independent effect of ESBL-positive and negative BSI on LOS.

Results

The incidence rate of ESBL-E BSI was of 1.52 cases/1000 patient-days (95% CI: 1.2–5.6 cases per 1000 patient-days). Multivariate analysis showed that independent risk factors for ESBL-BSI acquisition were related to underlying comorbidities (sickle cell disease OR = 3.1 (95%CI: 2.3–4.9), malnutrition OR = 2.0 (95%CI: 1.7–2.6)) and invasive procedures (mechanical ventilation OR = 3.5 (95%CI: 2.7–5.3)). Neonates were also identified to be at risk for ESBL-E BSI. Inadequate initial antibiotic therapy was more frequent in ESBL-positive BSI than ESBL-negative BSI (94.2% versus 5.7%, p<0.0001). ESBL-positive BSI was associated with higher case-fatality rate than ESBL-negative BSI (54.8% versus 15.4%, p<0.001). Multistate modelling indicated an excess LOS attributable to ESBL production of 4.3 days. The adjusted end-of-LOS hazard ratio for ESBL-positive BSI was 0.07 (95%CI, 0.04–0.12).

Conclusion

Control of ESBL-E spread is an emergency in pediatric populations and could be achieved with simple cost-effective measures such as hand hygiene, proper management of excreta and better stewardship of antibiotic use, especially for empirical therapy.

Epidemiology and economics of adult patients hospitalized with urinary tract infections

BACKGROUND

Urinary tract infections (UTI) are among the most common bacterial diseases worldwide, with significant clinical and economic burden. Surveillance of pathogen epidemiology and risk factors for resistant pathogens in the hospital setting may improve the management of UTI.

OBJECTIVE

To evaluate microbiology and antimicrobial susceptibility of UTI pathogens, with associated costs, in hospitalized patients.

METHODS

Patients diagnosed with UTI between July and September 2013 were retrospectively screened for clinical symptoms and treatment within 24 hours of admission, then categorized into groups: community acquired (Group 1); recent healthcare exposure (Group 2); or a history of identification of an extended-spectrum beta lactamase (ESBL)-producing organism (Group 3). Clinical, epidemiological, and financial data were compared between groups.

RESULTS

From 308 included patients, a total of 216 pathogens were identified. Escherichia coli was most commonly identified pathogen, but frequencies differed between groups (p = 0.002), as did those of ESBL-producing pathogens (p < 0.001) and Pseudomonas aeruginosa (p = 0.005). Appropriate empirical therapy also differed between groups (p = 0.003). Length of stay was longer for healthcare associated UTI with inappropriate empirical therapy (5.2 versus 6.3 days, p = 0.016). Increased cost was associated with factors other than antimicrobial costs. Intensive care unit (ICU) stay (p < 0.001), care facility at discharge (p = 0.001), Foley catheter (FC) present on admission (p = 0.002), and Charlson comorbidity index (CCI) (p = 0.017) predicted increased cost overall, while ICU stay (p < 0.001), time to appropriate therapy (p < 0.001), and CCI (p = 0.015) predicted higher cost in patients with pathogens identified.

CONCLUSIONS

Changes in antimicrobial susceptibility are evident with exposure to healthcare, the presence of a FC, and a history of resistant pathogens. Risk-based empirical prescribing and rapid de-escalation may improve care and reduce costs.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Impact of infection with extended-spectrum β-lactamase-producing Escherichia coli or Klebsiella species on outcome and hospitalization costs

BACKGROUND

Extended-spectrum β-lactamase (ESBL)-producing bacteria are important sources of infection; however, Canadian data evaluating the impact of ESBL-associated infection are lacking.

AIM

To determine whether patients infected with ESBL-producing Escherichia coli or Klebsiella species (ESBL-EcKs) exhibit differences in clinical outcome, microbiological outcome, mortality, and/or hospital resource use compared to patients infected with non-ESBL-producing strains.

METHODS

A retrospective case-control study of 75 case patients with ESBL-EcKs matched to controls infected with non-ESBL-EcKs who were hospitalized from June 2010 to April 2013 was conducted. Patient-level cost data were provided by the institution's business office. Clinical data were collected using the electronic databases and paper charts.

FINDINGS

Median infection-related hospitalization costs per patient were greater for cases than controls (C$10,507 vs C$7,882; median difference: C$3,416; P = 0.04). The primary driver of increased costs was prolonged infection-related hospital length of stay (8 vs 6 days; P = 0.02) with patient location (ward, ICU) and indirect care costs (including costs associated with infection prevention and control) as the leading cost categories. Cases were more likely to experience clinical failure (25% vs 11%; P = 0.03), with a higher all-cause mortality (17% vs 5%; P = 0.04). Less than half of case patients were prescribed appropriate empiric antimicrobial therapy, whereas controls received adequate initial treatment in nearly all circumstances (48% vs 96%; P < 0.01).

CONCLUSION

Patients with infection caused by ESBL-EcKs are at increased risk for clinical failure and mortality, with additional cost to the Canadian healthcare system of C$3,416 per patient.

Trends in Expanded-Spectrum Cephalosporin-Resistant Escherichia coli and Klebsiella pneumoniae among Dutch Clinical Isolates, from 2008 to 2012

We investigated time trends in extended-spectrum cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae isolates from different patient settings in The Netherlands from 2008–2012. E. coli and K. pneumoniae isolates from blood and urine samples of patients > = 18 years were selected from the Dutch Infectious Disease Surveillance System-Antimicrobial Resistance (ISIS-AR) database. We used multivariable Poisson regression to study the rate per year of blood stream infections by susceptible and resistant isolates, and generalized estimating equation (GEE) log-binomial regression for trends in the proportion of extended-spectrum cephalosporin-resistant isolates. Susceptibility data of 197,513 E. coli and 38,244 K. pneumoniae isolates were included. The proportion of extended-spectrum cephalosporin-resistant E. coli and K. pneumoniae isolates from urine and blood samples increased in all patient settings, except for K. pneumoniae isolates from patients admitted to intensive care units. For K. pneumoniae, there was a different time trend between various patient groups (p<0.01), with a significantly higher increase in extended-spectrum cephalosporin-resistant isolates from patients attending a general practitioner than in isolates from hospitalized patients. For E. coli, the increasing time trends did not differ among different patient groups. This nationwide study shows a general increase in extended-spectrum cephalosporin-resistant E. coli and K. pneumoniae isolates. However, differences in trends between E. coli en K. pneumoniae underline the importance of E. coli as a community-pathogen and its subsequent influence on hospital resistance level, while for K. pneumoniae the level of resistance within the hospital seems less influenced by the resistance trends in the community.

Clinical and economic impact of urinary tract infections caused by ESBL-producing Escherichia coli requiring hospitalization: A matched cohort study

OBJECTIVE

To analyze the clinical and economic impact of urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli requiring hospitalization.

METHODS

Matched cohort study including adults with UTI caused by ESBL-producing E. coli admitted to a tertiary care hospital in Barcelona, Spain, between August 2010 and July 2013. Demographic, clinical and economic data were analyzed.

RESULTS

One hundred and twenty episodes of UTI were studied: 60 due to ESBL-producing E. coli and 60 due to non-ESBL-producing E. coli. Bivariate analysis showed that prior antimicrobial treatment (p = 0.007) and ESBL production (p < 0.001) were related to clinical failure during the first 7 days. Multivariate analysis selected ESBL as the sole risk factor for clinical failure (p = 0.002). Regarding the economic impact of infections caused by ESBL-producing E. coli, an ESBL-producing infection cost more than a non-ESBL-producing E. coli infection (mean €4980 vs. €2612). Looking at hospital expenses separately, the total pharmacy costs and antibiotic costs of ESBL infections were considerably higher than for non-ESBL infections (p < 0.001), as was the need for outpatient parenteral antibiotic therapy (OPAT) and its related costs. Multivariate analysis performed for the higher costs of UTI episodes found statistically significant differences for males (p = 0.004), chronic renal failure (p = 0.025), ESBL production (p = 0.008) and OPAT (p = 0.009).

CONCLUSION

UTIs caused by EBSL-producing E. coli requiring hospital admission are associated with worse clinical and economic outcomes.

Antimicrobial stewardship - can we afford to do without it?

Antimicrobial resistance (AMR) is a rapidly developing and alarming global threat which has been highlighted by national governments and public health bodies including the World Health Organization. The spectre of a 'post-antibiotic era' is a real possibility unless curtailing the development and spread of these organisms is given high priority. Numerous studies have shown that AMR is associated with worse outcomes for patients and higher healthcare costs. While clinical data from low and middle income countries is lacking, there is increasing evidence that the problem in these areas is as great, or even greater, than in high income nations. Of the many drivers behind the development of AMR, the most significant is selection pressure caused by antibiotic use. Antimicrobial stewardship programmes are a set of interventions that aim to ensure the judicious use of antimicrobials by preventing their unnecessary use, and by providing targeted and limited therapy in situations where they are warranted. The ultimate goal of these programmes is to provide effective antimicrobial therapy whilst safeguarding their effectiveness for future generations. Whilst they do require an initial investment, they have been shown to be an effective way of controlling antimicrobial use, and have been associated with improved patient outcomes and reduced healthcare costs.