Diagnosis and antimicrobial treatment of invasive infections due to multidrug-resistant Enterobacteriaceae. Guidelines of the Spanish Society of Infectious Diseases and Clinical Microbiology

Temocillin versus meropenem for the targeted treatment of bacteraemia due to third-generation cephalosporin-resistant Enterobacterales (ASTARTÉ): protocol for a randomised, pragmatic trial

INTRODUCTION

Alternatives to carbapenems are needed in the treatment of third-generation cephalosporin-resistant Enterobacterales (3GCR-E). Temocillin is a suitable candidate, but comparative randomised studies are lacking. The objective is to investigate if temocillin is non-inferior to carbapenems in the targeted treatment of bacteraemia due to 3GCR-E.

METHODS AND ANALYSIS

Multicentre, open-label, randomised, controlled, pragmatic phase 3 trial. Patients with bacteraemia due to 3GCR-E will be randomised to receive intravenously temocillin (2 g three times a day) or carbapenem (meropenem 1 g three times a day or ertapenem 1 g once daily). The primary endpoint will be clinical success 7-10 days after end of treatment with no recurrence or death at day 28. Adverse events will be collected; serum levels of temocillin will be investigated in a subset of patients. For a 10% non-inferiority margin, 334 patients will be included (167 in each study arm). For the primary analysis, the absolute difference with one-sided 95% CI in the proportion of patients reaching the primary endpoint will be compared in the modified intention-to-treat population.

ETHICS AND DISSEMINATION

The study started after approval of the Spanish Regulatory Agency and the reference institutional review board. Data will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04478721.

Quasiexperimental intervention study protocol to optimise the use of new antibiotics in Spain: the NEW_SAFE project

INTRODUCTION

Ceftaroline, tedizolid, dalbavancin, ceftazidime-avibactam and ceftolozane-tazobactam are novel antibiotics used to treat infections caused by multidrug-resistant pathogens (MDR). Their use should be supervised and monitored as part of an antimicrobial stewardship programme (ASP). Appropriate use of the new antibiotics will be improved by including consensual indications for their use in local antibiotic guidelines, together with educational interventions providing advice to prescribers to ensure that the recommendations are clearly understood.

METHODS AND ANALYSIS

This study will be implemented in two phases. First, a preliminary historical cohort (2017-2019) of patients from 13 Andalusian hospitals treated with novel antibiotics will be analysed. Second, a quasiexperimental intervention study will be developed with an interrupted time-series analysis (2020-2021). The intervention will consist of an educational interview between prescribers and ASP leaders at each hospital to reinforce the proper use of novel antibiotics. The educational intervention will be based on a consensus guideline designed and disseminated by leaders after the retrospective cohort data have been analysed. The outcomes will be acceptance of the intervention and appropriateness of prescription. Incidence of infection and colonisation with MDR organisms as well as incidence of Clostridioides difficile infection will also be analysed. Changes in prescription quality between periods and the safety profile of the antibiotics in terms of mortality rate and readmissions will also be measured.

ETHICS AND DISSEMINATION

Ethical approval will be obtained from the Andalusian Coordinating Institutional Review Board. The study is being conducted in compliance with the protocol and regulatory requirements consistent with International Council of Harmonisation E6 Good Clinical Practice and the ethical principles of the latest version of the Declaration of Helsinki. The results will be published in peer-reviewed journals and disseminated at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT03941951; Pre-results.

[Risk factors and clinical evolution of carbapenemase-producing Klebsiella pneumoniae infections in a university hospital in Spain. Case-control study]

OBJECTIVE

Carbapenemase-producing Enterobacterias is a global health hazard due to their ease of transmission, difficulty of treatment, and their personal and economic impact. We analyze the factors associated with an increased risk of infection by Klebsiella pneumoniae carbapenemase-producing bacteria (KPC) and factors related to poor prognosis.

METHODS

We designed a case-control study. KPC isolates were taken during an outbreak in a hospital in Madrid. A logistic regression was performed with the main variables.

RESULTS

Sixteen cases of clinically documented infections were isolated. Overall mortality rates in the cases group was 25%. The most frequent location was blood (37.5%) followed by urine (25%). All but one were OXA-48. Regarding factors related to an increased risk of developing infection, only previous exposure to antibiotics presented statistical significance difference OR 13 (2.40-70.46). With respect to the overall mortality, the presence of pneumonia OR 25 (1.93-323.55) or the use of invasive mechanical ventilation was associated with greater risk 15 OR 33 (1.92-122.8) For attributable mortality only invasive ventilation had a significant association OR 18 (1.48-218.95).

CONCLUSIONS

Exposure to previous antibiotics is an independent risk factor for developing KPC infection, adjusted for all other clinical and demographic variables. Risk factors such as the presence of pneumonia or the use of invasive mechanical ventilation were associated with a worse prognosis in terms of overall and attributable mortality.

Phenotypic and molecular identification of carbapenemase-producing Enterobacteriaceae - challenges in diagnosis and treatment

Introduction: Infections due to carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CPCRE) are an emerging global public health threat. The purpose of this study was to investigate phenotypic and genotypic features of CP-CRE strains isolated from hospitalized patients. Material and methods: Between 1st of January - 1st of July 2017, in the Department of Microbiology, “Dr. Constantin Opriş” County Emergency Hospital Baia Mare, Romania, 1110 strains of Enterobacteriaceae were isolated from bronchial secretions, urine, wounds and blood cultures. Bacterial identification and antimicrobial susceptibility tests were performed by conventional methods, Vitek 2 Compact and M.I.C.E. strips. We analysed all Enterobacteriaceae strains non-susceptible to carbapenems according to CLSI 2017 criteria. The modified Hodge test (MHT), the modified carbapenem inactivation method (mCIM) and the combination disks test (KPC, MBL, OXA-48 Confirm kit, Rosco Diagnostica) were used for phenotypic confirmation, whereas a multiplex PCR assay for genes blaKPC, blaNDM and blaOXA-48 was used for genetic confirmation. Results: 19 non-duplicate strains isolated from 16 patients were phenotypically identified as CP-CRE: Klebsiella pneumoniae (n=14), Escherichia coli (n=2), Providencia stuartii (n=2) and Serratia marcescens (n=1). Most strains were isolated from bronchial secretions (n=9). The carbapenem-hydrolizing enzymes were identified by the combination disks test as: KPC (n=9), OXA-48-like (n=5) and MBL (n=5). Molecular confirmation was performed in 18 phenotypically positive isolates with 100% concordant results with mCIM and combination disks test. Discrepant results were noticed with the MHT in case of 4 NDM-producers confirmed by PCR. All CP-CRE strains were resistant to all tested cephems. Three out of 9 K. pneumoniae strains tested against colistin were found resistant. Conclusions: The most common carbapenemase detected was KPC. Therapeutic options were limited in all positive cases. Rapid and reliable detection of CP-CRE is critical for preventing the spread of these pathogens

The management of multidrug-resistant Enterobacteriaceae

PURPOSE OF REVIEW

Multidrug-resistant (MDR) Enterobacteriaceae are often related to the production of extended-spectrum b-lactamases (ESBLs) and carbapenemase-producing Enterobacteriaceae (CRE), and represent an increasing global threat. Recommendations for the therapeutic management of MDR-related infections, however, are mainly derived from retrospective and nonrandomized prospective studies. The aim of this review is to discuss the challenges in the treatment of patients with infections because of MDR Enterobacteriaceae and provide an expert opinion while awaiting for more definitive data.

RECENT FINDINGS

To avoid the selection of carbapenemase-producing Enterobacteriaceae, carbapenem-sparing strategies should be considered. B-lactams/b-lactamase inhibitors, mainly piperacillin-tazobactam, minimum inhibitory concentration (MIC) 16/4mg/ml or less represents the best alternative to carbapenems for the treatment of ESBL-producing strains. Overall, combination therapy may be preferred over monotherapy for CRE. The combination of a carbapenem-containing regimen with colistin or high-dose tigecycline or aminoglycoside can be administered at high-dose prolonged infusion with therapeutic drug monitoring for the treatment of CRE with MIC for meropenem 8-16 mg/l or less. For MIC higher than 8-16 mg/l, the use of meropenem should be avoided and various combination therapies based on the in-vitro susceptibility of antimicrobials (e.g., colistin, high-dose tigecycline, fosfomycin, and aminoglycosides) should be selected.

SUMMARY

Carbapenem-sparing strategies should be used, when feasible, for ESBL infections. The majority of available nonrandomized studies highlight that combination for CRE seem to offer some therapeutic advantage over monotherapy. Strict infection control measures toward MDR Gram-negative pathogens remain necessary while awaiting for new treatment options.

Is It Time to Rethink the Notion of Carbapenem-Sparing Therapy Against Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae Bloodstream Infections? A Critical Review

OBJECTIVE

To present systematic recommendations for carbapenem-sparing therapy against extended-spectrum β-lactamases (ESBLs) Enterobacteriaceae bloodstream infections (BSIs) derived from a critical review of clinical data.

DATA SOURCES

A systematic literature search using PubMed and MEDLINE databases (January 1, 2012, to June 30, 2017) was performed using key MESH terms: ESBL or extended-spectrum β-lactamases and bacteremia or bloodstream infection with piperacillin/tazobactam, ciprofloxacin, levofloxacin, cefepime, cephamycins, carbapenem, doripenem, meropenem, and ertapenem. References within articles of interest were also evaluated.

STUDY SELECTION AND DATA EXTRACTION

All English language trials were considered, and results were limited to clinical efficacy trials. Articles were screened by title and abstract for inclusion.

DATA SYNTHESIS

Studies comparing noncarbapenem versus carbapenem therapy for ESBL BSIs were critically analyzed to identify heterogeneity among studies. Data abstracted included empirical or definitive therapy, patient population, dosing, source of infection and severity, infectious etiology, and outcome.

CONCLUSIONS

Completely sparing carbapenem therapy cannot be justified among patients with ESBL BSIs. Determining the source of infection is critical to identify patients for whom carbapenem-sparing therapy is appropriate.

Extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae from urinary tract infections: Evolution of antimicrobial resistance and treatment options

BACKGROUND AND OBJECTIVES

A study of the susceptibility to antimicrobials of the extended spectrum beta-lactamase phenotypes (ESBL) in Escherichia coli and Klebsiella spp. was performed to discover the evolution of this type of resistance from urinary tract infections.

MATERIAL AND METHOD

A retrospective study was carried out between 2012 and 2016. Susceptibility to ciprofloxacin, tobramycin, cefoxitin, fosfomycin, nitrofurantoin, co-trimoxazole, and carbapenems was analyzed using MicroScan^® system.

RESULTS

A total of 95,399 samples were processed and 9,772 E. coli, 1,784 Klebsiella pneumoniae and 248 Klebsiella oxytoca were isolated. ESBL strains were more frequent in women, although they decreased during 2015 and 2016 (65.7-67.2%). The prevalence of K. pneumoniae ESBL increased annually (28.1% in 2016). The average prevalence of E. coli ESBL was 10.5% with few oscillations. Higher resistance occurred to ciprofloxacin and cotrimoxazole, 89.5 and 94.7% in 2015, respectively, and there was lesser resistance to imipenem. Fosfomycin and nitrofurantoin were very active on E. coli ESBL.

CONCLUSIONS

ESBL producing E. coli and K. pneumoniae were prevalent, especially the latter, with a significant resistance to ciprofloxacin and cotrimoxazole. Susceptibility to imipenem was high.

Mortality Associated with Bacteremia Due to Colistin-Resistant Klebsiella pneumoniae with High-Level Meropenem Resistance: Importance of Combination Therapy without Colistin and Carbapenems

Combination therapy including colistin and a carbapenem has been found to be associated with lower mortality in the treatment of bloodstream infections (BSI) due to KPC-producing Klebsiella pneumoniae when the isolates show a meropenem or imipenem MIC of <16 mg/liter. However, the optimal treatment of BSI caused by colistin- and high-level carbapenem-resistant KPC-producing K. pneumoniae is unknown. A prospective cohort study including episodes of bacteremia caused by colistin-resistant and high-level meropenem-resistant (MIC ≥ 64 mg/liter) KPC-producing K. pneumoniae diagnosed from July 2012 to February 2016 was performed. The impact of combination therapy on crude 30-day mortality was analyzed by Cox regression using a propensity score as a covariate to control for indication bias and in an inverse probability of treatment weighting (IPTW) cohort. The study sample comprised 104 patients, of which 32 (30.8%) received targeted monotherapy and 72 (69.2%) received targeted combination therapy; none of them received either colistin or a carbapenem. The 30-day crude mortality rate was 30.8% (43.8% in patients treated with monotherapy and 25% in patients receiving combination therapy). In the Cox regression analysis, 30-day mortality was independently associated with septic shock at BSI onset (hazard ratio [HR], 6.03; 95% confidence interval [CI], 1.65 to 21.9; P = 0.006) and admission to the critical care unit (HR, 2.87; 95% CI, 0.99 to 8.27; P = 0.05). Targeted combination therapy was associated with lower mortality only in patients with septic shock (HR, 0.14; 95% CI, 0.03 to 0.67; P = 0.01). These results were confirmed in the Cox regression analysis of the IPTW cohort. Combination therapy is associated with reduced mortality in patients with bacteremia due to colistin-resistant KPC-producing K. pneumoniae with high-level carbapenem resistance in patients with septic shock.

Effect of appropriate combination therapy on mortality of patients with bloodstream infections due to carbapenemase-producing Enterobacteriaceae (INCREMENT): a retrospective cohort study

BACKGROUND

The best available treatment against carbapenemase-producing Enterobacteriaceae (CPE) is unknown. The objective of this study was to investigate the effect of appropriate therapy and of appropriate combination therapy on mortality of patients with bloodstream infections (BSIs) due to CPE.

METHODS

In this retrospective cohort study, we included patients with clinically significant monomicrobial BSIs due to CPE from the INCREMENT cohort, recruited from 26 tertiary hospitals in ten countries. Exclusion criteria were missing key data, death sooner than 24 h after the index date, therapy with an active antibiotic for at least 2 days when blood cultures were taken, and subsequent episodes in the same patient. We compared 30 day all-cause mortality between patients receiving appropriate (including an active drug against the blood isolate and started in the first 5 days after infection) or inappropriate therapy, and for patients receiving appropriate therapy, between those receiving active monotherapy (only one active drug) or combination therapy (more than one). We used a propensity score for receiving combination therapy and a validated mortality score (INCREMENT-CPE mortality score) to control for confounders in Cox regression analyses. We stratified analyses of combination therapy according to INCREMENT-CPE mortality score (0-7 [low mortality score] vs 8-15 [high mortality score]). INCREMENT is registered with ClinicalTrials.gov, number NCT01764490.

FINDINGS

Between Jan 1, 2004, and Dec 31, 2013, 480 patients with BSIs due to CPE were enrolled in the INCREMENT cohort, of whom we included 437 (91%) in this study. 343 (78%) patients received appropriate therapy compared with 94 (22%) who received inappropriate therapy. The most frequent organism was Klebsiella pneumoniae (375 [86%] of 437; 291 [85%] of 343 patients receiving appropriate therapy vs 84 [89%] of 94 receiving inappropriate therapy) and the most frequent carbapenemase was K pneumoniae carbapenemase (329 [75%]; 253 [74%] vs 76 [81%]). Appropriate therapy was associated with lower mortality than was inappropriate therapy (132 [38·5%] of 343 patients died vs 57 [60·6%] of 94; absolute difference 22·1% [95% CI 11·0-33·3]; adjusted hazard ratio [HR] 0·45 [95% CI 0·33-0·62]; p<0·0001). Among those receiving appropriate therapy, 135 (39%) received combination therapy and 208 (61%) received monotherapy. Overall mortality was not different between those receiving combination therapy or monotherapy (47 [35%] of 135 vs 85 [41%] of 208; adjusted HR 1·63 [95% CI 0·67-3·91]; p=0·28). However, combination therapy was associated with lower mortality than was monotherapy in the high-mortality-score stratum (30 [48%] of 63 vs 64 [62%] of 103; adjusted HR 0·56 [0·34-0·91]; p=0·02), but not in the low-mortality-score stratum (17 [24%] of 72 vs 21 [20%] of 105; adjusted odds ratio 1·21 [0·56-2·56]; p=0·62).

INTERPRETATION

Appropriate therapy was associated with a protective effect on mortality among patients with BSIs due to CPE. Combination therapy was associated with improved survival only in patients with a high mortality score. Patients with BSIs due to CPE should receive active therapy as soon as they are diagnosed, and monotherapy should be considered for those in the low-mortality-score stratum.

FUNDING

Spanish Network for Research in Infectious Diseases, European Development Regional Fund, Instituto de Salud Carlos III, and Innovative Medicines Initiative.

EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA): a protocol of a European multicentre observational study

INTRODUCTION

The rapid worldwide spread of carbapenem-resistant Enterobacteriaceae (CRE) constitutes a major challenge. The aim of the EUropean prospective cohort study on Enterobacteriaceae showing REsistance to CArbapenems (EURECA), which is part of the Innovative Medicines Initiative Joint Undertaking (IMI JU) funded COMBACTE-CARE project, is to investigate risk factors for and outcome determinants of CRE infections to inform randomised clinical trial designs and to provide a historical cohort that could eventually be used for future comparisons with new drugs targeting CRE.

METHODS

A multicentre (50 sites), multinational (11 European countries), analytical observational project was designed, comprising 3 studies. The aims of study 1 (a prospective cohort study) include characterising the features, clinical management and outcomes of hospitalised patients with intra-abdominal infection, pneumonia, complicated urinary tract infections and bloodstream infections caused by CRE (202 patients in each group). The main outcomes will be 30-day all-cause mortality and clinical response. Study 2 (a nested case-control study) will identify the risk factors for target infections caused by CRE; 248 selected patients from study 1 will be matched with patients with carbapenem-susceptible Enterobacteriaceae (1:1) and with hospitalised patients (1:3) and will provide a historical cohort of patients with CRE infections. Study 3 (a matched cohort study) will follow patients in study 2 in order to assess mortality, length of stay and hospital costs associated with CRE. All patients will be followed for 30 days. Different, up-to-date statistical methods will be applied to come to unbiased estimates for all 3 studies.

ETHICS AND DISSEMINATION

Before-study sites will be initiated, approval will be sought from appropriate regulatory agencies and local Ethics Committees of Research or Institutional Review Boards (IRBs) to conduct the study in accordance with regulatory requirements. This is an observational study and therefore no intervention in the diagnosis, management or treatment of the patients will be required on behalf of the investigation. Any formal presentation or publication of data collected from this study will be considered as a joint publication by the participating physician(s) and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE) for authorship.

TRIAL REGISTRATION NUMBER

NCT02709408.

Patient specific risk stratification for antimicrobial resistance and possible treatment strategies in gram-negative bacterial infections

INTRODUCTION

The isolation of multi-drug-resistant gram-negative (MDRGN) pathogens has progressively increased worldwide and has been associated with important delays in the prescription of an adequate antibiotic treatment, resulting in increased mortality rates. Patient's stratification for MDRGN infections to optimize the prescription of an adequate empiric antimicrobial regimen is crucial. Areas covered: This article covers MDRGN epidemiology, with a specific focus on risk factors for harbouring infections sustained by extended-spectrum-Beta-lactamase (ESBL), carbapenem resistant Enterobacteriacae (CRE), MDR Pseudomonas aeruginosa and MDR Acinetobacter baumanii. Moreover, we will propose an algorithm for the choice of empiric treatment when a MDRGN infection is suspected. Expert commentary: Although in clinical practice, a patient's stratification represents a challenge, whenever a MDRGN pathogen is suspected broad-spectrum, combination empiric treatment should be promptly started, looking for a balance between the prescription of an adequate empiric treatment and the risk of resistance selection.

A Predictive Model of Mortality in Patients With Bloodstream Infections due to Carbapenemase-Producing Enterobacteriaceae

OBJECTIVE

To develop a score to predict mortality in patients with bloodstream infections (BSIs) due to carbapenemase-producing Enterobacteriaceae (CPE).

PATIENTS AND METHODS

A multinational retrospective cohort study (INCREMENT project) was performed from January 1, 2004, through December 31, 2013. Patients with clinically relevant monomicrobial BSIs due to CPE were included and randomly assigned to either a derivation cohort (DC) or a validation cohort (VC). The variables were assessed on the day the susceptibility results were available, and the predictive score was developed using hierarchical logistic regression. The main outcome variable was 14-day all-cause mortality. The predictive ability of the model and scores were measured by calculating the area under the receiver operating characteristic curve. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for different cutoffs of the score.

RESULTS

The DC and VC included 314 and 154 patients, respectively. The final logistic regression model of the DC included the following variables: severe sepsis or shock at presentation (5 points); Pitt score of 6 or more (4 points); Charlson comorbidity index of 2 or more (3 points); source of BSI other than urinary or biliary tract (3 points); inappropriate empirical therapy and inappropriate early targeted therapy (2 points). The score exhibited an area under the receiver operating characteristic curve of 0.80 (95% CI, 0.74-0.85) in the DC and 0.80 (95% CI, 0.73-0.88) in the VC. The results for 30-day all-cause mortality were similar.

CONCLUSION

A validated score predictive of early mortality in patients with BSIs due to CPE was developed.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01 764490.

Community-Onset Bloodstream and Other Infections, Caused by Carbapenemase-Producing Enterobacteriaceae: Epidemiological, Microbiological, and Clinical Features

Background. Because most infections caused by carbapenemase-producing Enterobacteriaceae (CPE) begin during hospitalization, there are limited data about community-onset (CO) infections caused by CPE. Our aim is to describe the frequency of CO infections caused by CPE as well as the clinical features of CO bloodstream infections (CO-BSIs).

Methods. This study includes retrospective case series of CO infections caused by CPE in a tertiary hospital from January 2010 to July 2014. Any clinical sample with a positive culture for CPE that had been ordered by primary care doctors or by doctors at the emergency room (ER) were classified as CO. Epidemiological and microbiological features of CO cases were assessed as were clinical features of CO-BSIs.

Results. Of 780 clinical samples with CPE, 180 were requested at the ER or by primary care doctors (22.9%), 150 of which were produced by Klebsiella pneumoniae (83.3%). The bla_OXA−48 gene was detected in 149 isolates (82.8%) followed by the bla_VIM gene, 29 (16.1%). Sixty-one patients (33.9%) had a prior history of CPE infection/colonization. Thirty-four of the 119 (28.6%) patients without prior history of CPE infection/colonization did not fulfill Friedman criteria for healthcare-associated infections (HAIs). Considering previous hospitalization of up to 12 months as a criterion for defining HAI, only 16 (13.4%) cases were identified as community-acquired infections. The most frequent positive sample was urine (133 of 180; 73.9%). Twenty-one (11.7%) patients had a BSI, 9 of them secondary to urinary tract infections (42.9%). Thirty-day crude mortality among patients with BSI was 23.8% (5 of 21).

Conclusions. Community-onset infections caused by CPE are an important subgroup of all CPE infections. The urinary tract is the main source. Bloodstream infections accounted for more than 10% of the cases.

Carbapenemase-Producing Klebsiella pneumoniae, a Key Pathogen Set for Global Nosocomial Dominance

The management of infections due to Klebsiella pneumoniae has been complicated by the emergence of antimicrobial resistance, especially to carbapenems. Resistance to carbapenems in K. pneumoniae involves multiple mechanisms, including the production of carbapenemases (e.g., KPC, NDM, VIM, OXA-48-like), as well as alterations in outer membrane permeability mediated by the loss of porins and the upregulation of efflux systems. The latter two mechanisms are often combined with high levels of other types of β-lactamases (e.g., AmpC). K. pneumoniae sequence type 258 (ST258) emerged during the early to mid-2000s as an important human pathogen and has spread extensively throughout the world. ST258 comprises two distinct lineages, namely, clades I and II, and it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Incompatibility group F plasmids with blaKPC have contributed significantly to the success of ST258. The optimal treatment of infections due to carbapenemase-producing K. pneumoniae remains unknown. Some newer agents show promise for treating infections due to KPC producers; however, effective options for the treatment of NDM producers remain elusive.

Executive summary of the diagnosis and antimicrobial treatment of invasive infections due to multidrug-resistant Enterobacteriaceae. Guidelines of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC)

The spread of multidrug-resistant Enterobacteriaceae related to the production of extended-spectrum β-lactamases (ESBL) and carbapenemases is a serious public health problem worldwide. Microbiological diagnosis and therapy of these infections are challenging and controversial. After the selection of clinically relevant questions, this document provides evidence-based recommendations for the use of microbiological techniques for the detection of ESBL- and carbapenemase-producing Enterobacteriaceae, and for antibiotic therapy for invasive infections caused by these organisms. The absence of randomized-controlled trials is noteworthy, thus recommendations are mainly based on observational studies, that have important methodological limitations, pharmacokinetic and pharmacodynamics models, and data from animal studies. Additionally, areas for future research were identified.