Carbapenem-resistant Enterobacteriaceae colonization (CRE) and subsequent risk of infection and 90-day mortality in critically ill patients, an observational study

Risk factors for household colonization by extended-spectrum cephalosporin-resistant enterobacterales (ESCrE) in Botswana

BACKGROUND

The epidemiology of community colonization with extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in low- and middle-income countries (LMICs) is largely uncharacterized. In the community, the household is of particular importance. Identifying risk factors for household ESCrE colonization is critical to inform antibiotic resistance reduction strategies.

METHODS

Participants were enrolled at 6 clinics in Botswana. All participants had rectal swabs collected for selective plating and confirmation of ESCrE. Data were collected on demographics, comorbidities, antibiotic use, healthcare exposures, travel, and farm/animal contact. Households were considered exposed if any member had the exposure of interest. Households with ESCrE colonization (cases) were compared to non-colonized households (controls) to identify risk factors for household ESCrE colonization.

RESULTS

From 1/1/20 - 9/4/20, 327 households were enrolled. The median (IQR) number of people enrolled per household was 3 (2-4) ranging from 2 to 10. The median (IQR) age of subjects was 18 years (5-34) and 304 (93%) households included at least one child. Of 327 households, 176 (54%) had at least one household member colonized with ESCrE. Independent risk factors [adj OR (95%CI)] for household colonization were: (1) horse/donkey exposure [2.32 (1.05, 5.10)]; (2) yogurt consumption [1.73 (1.04, 2.88)]; (3) region [2.83 (1.48,5.43)]; and (4) enrollment during pre-COVID lockdown [2.90 (1.66, 5.05)].

CONCLUSIONS

ESCrE household colonization was common with evidence of geographic variability as well as a possible role of animal exposure. The role of yogurt exposure requires further study with consideration of source (commercial, homemade). Further prospective studies of household ESCrE colonization with longitudinal assessments of exposures are required to identify effective prevention strategies.

Carbapenem-resistant Enterobacterales bloodstream infections related to death in two Brazilian tertiary hospitals

BACKGROUND

Bloodstream infection (BSI) caused by carbapenem-resistant Enterobacterales (CRE) is a major global public health concern due to its high lethality and limited treatment options. In Brazil, CRE was first reported in 2005, with Klebsiella pneumoniae carbapenemase (KPC) documented in 2009. Despite ongoing reports, data remain limited in several regions.

OBJECTIVE

To describe the lethality rate and epidemiological and clinical characteristics of BSI patients with Enterobacterales BSI and assess carbapenem resistance to identify major risk factors for CRE infection and lethality.

METHODS

This prospective laboratory-based surveillance study, which was conducted in two tertiary hospitals (April 2016-December 2018), analyzed BSI cases caused by Enterobacterales. Clinical and demographic data were obtained from medical records. The bacterial isolates were identified by mass spectrometry and by VITEK-2®, with antimicrobial susceptibility testing performed by VITEK-2®. Logistic regression and Kaplan‒Meier survival analyses were used to assess the impact of CRE BSI on death.

RESULTS

Among 252 patients with enterobacterial BSIs were identified, of which 14.3% had CRE. The overall lethality rate was 37.7%. Compared with carbapenem-susceptible Enterobacterales, CRE-associated BSIs were associated with significantly greater lethality (71.6% vs. 28.4%; p < 0.001; OR = 6.53, 95% CI [3.01-15.41]). The association remained significant after adjusting for age, comorbidities, Pitt bacteremia score, Enterobacterales species, BSI type, and sepsis. All CRE BSI cases were hospital-acquired.

CONCLUSIONS

CRE accounts for 14.3% of BSIs and is strongly associated with increased lethality. Given the limited epidemiological data in Brazil, this study provides valuable epidemiological insights that may inform local treatment protocols for Enterobacterales infections.

Study on the correlation between Carbapenem-Resistant Klebsiella pneumoniae infection strains and intestinal colonization strains in Intensive Care Unit of a tertiary hospital in China

OBJECTIVES

Colonization by Carbapenem-Resistant Klebsiella pneumoniae (CRKP) is associated with the risk of developing CRKP infection. Whether infected strains come from colonized strains is not well known.

METHODS

An observational, prospective cohort study (July 2022 to June 2023) was conducted on ICU patients undergoing rectal CRKP colonization screening. Antibiotic susceptibility testing, modified carbapenem inactivation method (mCIM), serum bactericidal and phagocytic assays, and whole genome sequencing (WGS) were performed on intestinal colonization and infection site isolates from 7 ICU patients.

RESULTS

Among 412 ICU patients included, 88 were screened positive. Out of 82 patients who experienced colonization during hospitalization, 41 (50.0%) developed infections. 14 CRKP strains isolated from 7 patients were positive for carbapenemase in mCIM and exhibited similar resistance and virulence phenotype. WGS showed that the 14 CRKP, including 2 ST11, 2 ST15, and 10 ST5422, were blaKPC-2 producing strains, and the genetic environment surrounding blaKPC-2 was the same. Comparing the colonized and infected strains of the same patient, they both carried identical virulence genes, but the resistance genes and plasmids were not completely the same, however, the SNPs differed by less than 10.

CONCLUSIONS

Nosocomial CRKP infection should focus on preventing intestinal colonization in hospitalized patients. Small SNPs differences indicated that the infected strain may have originated from the colonized strain, but some resistance genes or plasmids may have been obtained during this transformation process. blaKPC-2-carrying K. pneumoniae ST5422 was first reported in our study, and its genetic relationship was closely related to the clone strain ST11.

Plasmid-bacteria associations in the clinical context

Antimicrobial resistance (AMR) is one of the most pressing global health problems, with plasmids playing a central role in its evolution and dissemination. Over the past decades, many studies have investigated the ecoevolutionary dynamics between plasmids and their bacterial hosts. However, what drives the epidemiological success of certain plasmid-bacterium associations remains unclear. In this opinion article, we review which factors influence these associations and underline that studying plasmid-host interactions of clinical relevance is critical for understanding the evolution and spread of AMR. We also highlight the increasing importance of integrating experimental research with bioinformatics and machine learning tools to study plasmid-bacteria dynamics. This combined approach will assist researchers to dissect the molecular mechanisms underlying successful plasmid-host associations and to design strategies to prevent and predict future high-risk associations.

Effectiveness and safety of oral antibiotics as a decolonization strategy for carbapenem-resistant Enterobacteriaceae: A systematic review of randomized and non-randomized studies

INTRODUCTION

Carbapenem-resistant Enterobacteriaceae (CRE) infections are associated with increased mortality and higher healthcare costs in hospitalized patients, making it reasonable to explore the effectiveness of strategies for decolonization of intestinal carriage.

OBJECTIVE

To evaluate the effectiveness and safety of oral and/or intravenous antibiotics in adults colonized by CRE.

METHODS

We conducted a systematic review of randomized clinical trials and nonrandomized studies comparing oral and/or intravenous antibiotic therapy versus no treatment or placebo in adults colonized by CRE. Outcomes assessed included eradication, infection rate, mortality, length of hospital stay, and adverse events. Searches were performed in the Embase, MEDLINE (PubMed), and Cochrane Library. Quality assessment was conducted using the ROB1 or ROBINS-I tool. Meta-analysis was performed using a random effects model in Review Manager, and the certainty of evidence was evaluated using the GRADE methodology.

RESULTS

Seven studies comprising 728 participants were included. Decolonization therapy was significantly associated with intestinal carriage eradication (OR: 2.66; 95% CI: 1.55-4.55; I2: 0%). There was a trend toward a reduced infection rate (OR: 0.66; 95% CI: 0.26-1.65; I2: 4%). Data on mortality and adverse events were limited and insufficient to draw conclusions about differences between groups. The certainty of evidence ranged from moderate to very low.

CONCLUSION

This study suggests that decolonization therapy may be effective in eradicating CRE intestinal carriage state, but current evidence is insufficient to determine its impact on infection rates, mortality, or adverse events. Larger, high-quality randomized clinical trials are necessary to generate robust evidence supporting its clinical use.

"Nebulized lidocaine for intractable cough in hospice care: a comprehensive review of efficacy, safety, and future perspectives"

BACKGROUND AND OBJECTIVE

Intractable cough, affecting 10-50% of terminally ill patients, significantly impairs quality of life. Conventional therapies often fail due to dose-limiting side effects or inadequate efficacy, necessitating alternative treatments. This review evaluates the efficacy, safety, and clinical applicability of nebulized lidocaine for managing intractable cough in hospice care.

METHODS

A systematic literature search (1973-2023) across PubMed, MEDLINE, Embase, and Cochrane Library identified studies on nebulized lidocaine in hospice or palliative populations. Inclusion criteria the Cochrane Risk of Bias Tool and Newcastle-Ottawa Scale. Data on cough reduction, side effects, and dosing were synthesized thematically.

RESULTS

Among 265 screened studies, 58 met inclusion criteria. Nebulized lidocaine (1-4%) demonstrated rapid cough suppression (within 15 min) in 70% of cancer patients, with effects lasting 2-4 h. Mild side effects, including oropharyngeal numbness (15%) and bitter taste (10%), were transient. However, 25% of asthmatic patients experienced bronchoconstriction (forced expiratory volume in 1 s FEV1FEV1 decline ≥ 15%), resolving with bronchodilators. Lidocaine reduced opioid reliance and improved comfort in 80% of cases. Variability in efficacy was noted, with limited benefits in severe chronic obstructive pulmonary disease (COPD) with acute respiratory failure.

CONCLUSION

Nebulized lidocaine offers a safe, non-invasive option for intractable cough in hospice care, minimizing systemic side effects. Its rapid action and compatibility with opioid-sparing regimens enhance palliative outcomes. However, cautious use is warranted in asthma and (COPD) due to bronchoconstriction risks. Future research should prioritize standardized dosing, long-term safety, and Randomized controlled trials(RCTs in diverse hospice populations.

Risk Factors for Carbapenem-Resistant Enterobacteriaceae Colonization in Intensive Care Units: A Meta-Analysis

Introduction: Infections due to carbapenem-resistant Enterobacteriaceae (CRE) in intensive care units (ICUs) pose a significant threat. Colonization with CRE is a prerequisite for bacterial translocation/infections. This work aimed to determine risk factors for CRE colonization in ICU patients. Methods: To find relevant works, PubMed, EMBASE, and references of eligible studies were systematically searched using appropriate keywords up to September 2023. Odds ratios (ORs) and 95% confidence intervals were used to compare risk factor between CRE colonized cases and CRE noncolonized controls. Results: Twelve studies were included. Previous hospitalization (OR: 2.26), previous ICU stay (OR: 10.33), higher acute physiology and chronic health evaluation (APACHE) II score (mean difference [MD]: 4.38), central venous catheter (OR: 4.07), long-term gastric tube (OR: 3.01), hemodialysis catheter (OR: 3.38), urinary catheter (OR: 2.59), mechanical ventilation (OR: 3.41), endoscopy (OR: 3.37), tracheostomy (OR: 3.46), and exposure to antibiotics such as glycopeptide (OR: 10.68), aminoglycosides (OR: 6.53), tigecycline (OR: 6.87), vancomycin (OR: 5.32), carbapenems (OR: 5.23), cephalosporins (OR: 4.96), metronidazole (OR: 4.82), penicillin (OR: 4.41), and β-lactams/β-lactamase inhibitor (OR: 4.28) are highly associated with CRE colonization. Conclusions: ICU-admitted patients with prior hospitalization, ICU stay, previous antibiotic use, and invasive devices/procedures exposures should be prioritized in the screening strategy for CRE colonization to prevent nosocomial infections.

Epidemiology and outcomes associated with MBL-producing Enterobacterales: A systematic literature review

The increasing prevalence of infections due to metallo-β-lactamase (MBL)-producing Enterobacterales poses a serious concern given the limited treatment options available. This systematic literature review (SLR) describes the molecular epidemiology, geographical distribution, and clinical outcomes of such infections. Systematic searches of literature published between January 2013 and May 2023 were performed, and 39 studies with an MBL sample size of ≥25 isolates and ≥2 well-defined outcomes were eligible. Most of the studies were from Asia (21/39) followed by Europe (11/39) and evaluated more than two species (24/39). Overall, the percentage of MBL-producing isolates ranged from 6.8%-100.0%. Among 6620 MBL-producers, the majority were from Europe (3837/6620; 58.0%), followed by Asia (2079/6620; 31.4%). New Delhi MBL (NDM)-producers (5668/6620; 85.6%) were the most frequent across all regions, with NDM-1 as the common variant. The majority of IMP-producing isolates (586/592; 99.0%) came from Asia, while the majority of VIM-producing isolates were found in Europe (322/371; 86.8%). Studies focused on MBL-specific outcomes (n = 28) reported reduced susceptibility (<80.0%) to most antimicrobials except for colistin and tigecycline. Six studies reported significantly longer hospital and/or ICU stay due to MBL-Enterobacterales compared to other infection groups. Common mortality measures reported were overall mortality (18.8%-57.0%; 9 studies), in-hospital mortality (11.1%-55.3%; 6 studies), and 30-day mortality (0%-36.4%; 7 studies). Previous antibiotic use (9 studies) and hospital and/or ICU stay (8 studies) were common risk factors for colonization/infection and mortality. Reporting of MBL prevalence across regions will provide a better understanding of the infection burden and prevent further spread.

Prevalence and mortality associated with multidrug-resistant infections in adult intensive care units in Argentina (PREV-AR)

Data from low and middle-income countries (LMICs) on multidrug-resistant microorganisms (MDROs) in intensive care units (ICUs) are scarce. Working in several ICUs in Argentina, we sought to estimate the prevalence and characteristics of MDRO infections and carbapenemase-producing Enterobacterales (CPE) colonization. Mortality associated with MDRO infection was also evaluated. The study was a 24-hour point prevalence study conducted in 164 adult ICUs in Argentina between 24 November and 28 November 2023. The main study outcome was in-ICU mortality and secondary outcomes included the prevalence of MDRO infections, the prevalence of CPE colonization (defined as CPE recovered from a rectal swab), and ICU length of stay (LoS). Mixed effects modeling was used to identify risk factors for in-ICU mortality. Among 1,799 patients, 933 (51.9%) had a reported infection; 599 infections (64.2%) were classified as definite (i.e., with positive cultures) and 334 (35.8%) as probable infection (i.e., negative cultures but signs of infection). Of the 933 patients with infection, 273 (29.2%) had an MDRO recovered with 344 total MDRO cultures recovered. Non-MDRO was recovered from 326 (34.9%) of the 933 patients. Among definite infections, 45.5% (273/599) were due to MDRO with an overall prevalence of MDRO of 15.1% (273 patients with MDRO infections/1,799 patients). CPE colonization, defined as a positive rectal swab taken during the incident hospitalization, occurred in 420/1,696 (24.7%) patients. The most frequent MDRO infection was ventilator-associated pneumonia (100/344; 29.1%). The most common MDRO recovered were carbapenem-resistant Acinetobacter baumannii and CPE (98/344, 28.5% each). In-ICU mortality was 27.1% (487/1,799); independent predictors were age (odds ratio [OR] 1.01 [1.00-1.02], P = 0.003), MDRO infection (OR 1.65 [1.18-2.43], P = 0.012), probable infection (OR 1.41 [0.97-2.04], P = 0.073), sepsis-related organ failure assessment (SOFA) score (OR 1.18 [1.13-1.23], P = 0.000), and hospital-acquired pneumonia (OR 1.84 [1.12-3.01], P = 0.016). Mortality also varied significantly by hospital (P < 0.001). LoS was significantly longer in patients with MDRO infections, 30.0 (interquartile range [IQR] 17-35) days vs 16.0 (IQR 8-33) in non-MDRO, P < 0.0001. Among 1,799 ICU patients in an LMIC, the prevalence of MDRO infection and CPE colonization was high. The presence of an MDRO infection was associated with increased mortality and prolonged ICU LoS.CLINICAL TRIALSThis study is registered with Clinicaltrials.gov as NCT06574776.

Carbapenem-resistant Enterobacterales (CRE) colonisation as a predictor for subsequent CRE infection: A retrospective surveillance study

Background

Carbapenem-resistant Enterobacterales (CRE) are associated with significant morbidity and mortality. Carbapenem-resistant Enterobacterales colonisation is an important prerequisite for infection, and its surveillance is crucial to reduce spread. However, data from South Africa are limited.

Objectives

We aimed to determine CRE colonisation prevalence, the incidence of subsequent CRE infections and the risk factors associated with each.

Method

We retrospectively reviewed hospital records from 686 patients admitted to a medical high-care ward at a tertiary hospital in Gauteng, South Africa, between October 2019 and May 2022. Patients were grouped by CRE colonisation status on arrival and discharge. Data on comorbidities, indwelling devices and antibiotic exposure were collected.

Results

The prevalence of CRE colonisation was 12.4% (95% confidence interval [CI]: 10.1-15.1), with Klebsiella pneumoniae (81.2%) being the most common CRE isolated and OXA-48-like enzymes (94.5%) being the most frequent carbapenemase detected. Risk factors for CRE colonisation on the univariate analysis included exposure to antibiotics (odds ratio [OR]: 2.21; 95% CI: 0.98-4.96, P = 0.048) and presence of a central venous line (OR: 6.33; 95% CI: 1.78-22.46, P = 0.001). Of patients colonised with a CRE, 21.2% subsequently developed a culture-positive infection within 180 days from the initial colonisation result and the majority within 30 days. These infections were mostly CREs (OR: 4.0, 95% CI: 1.3-12.7), and where the infections were CREs, the causative CRE organism and carbapenemase subtype were identical in each case.

Conclusion

Our study documented higher CRE prevalence rates than those previously reported from South Africa. Given the association between CRE colonisation and subsequent infection, urgent measures are required to reduce CRE colonisation rates. As the organism and carbapenemase detected in the initial colonisation and subsequent CRE infection were closely related, knowledge of prior CRE colonisation may assist clinicians with antibiotic choice if patients present with an infection within 30 days of CRE colonisation.

Contribution

This study reports higher CRE colonization rates in South Africa than previously documented, highlighting the urgent need to reduce colonization. The close genetic link between CRE colonization and subsequent infection suggests that knowledge of prior colonization can guide clinicians in selecting effective antibiotics, particularly for infections occurring within 30 days. These findings support targeted interventions to address the rising CRE threat.

Long-term Risk of Infection Among Patients Colonized With Antimicrobial-Resistant Pathogens: A Population-wide Cohort Study

Background

Antimicrobial-resistant (AMR) pathogens represent an ongoing global health burden. Colonization is often a prerequisite for infection, but the risk of infection after AMR colonization is not well understood. Using population-level health administrative data, we sought to investigate the risk of infection with the same AMR organism after detection of colonization.

Methods

We conducted a retrospective population-wide cohort study among residents of Ontario, Canada, over a 5-year period to determine the risk of infection after detection of colonization with the following AMR pathogens: methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, extended-spectrum β-lactamase-producing Enterobacterales, and carbapenemase-producing Enterobacterales. We also examined the effects of age, sex, and health care setting of colonization detection on subsequent infection risk.

Results

There were 69 998 individuals with a positive AMR pathogen surveillance test result during the study period, 15.6% of which subsequently developed a sterile or nonsterile site infection within a median 57 days (IQR, 11-228). Infection rates varied among organisms: 18.3% for methicillin-resistant S aureus within a median 57 days (IQR, 10-239), 2.8% for vancomycin-resistant Enterococcus within a median 37 days (IQR, 11-119), 21.5% for extended-spectrum β-lactamase-producing Enterobacterales within a median 71 days (IQR, 18-231), and 20.3% for carbapenemase-producing Enterobacterales within a median 10 days (IQR, 3-42). A positive surveillance test result detected in a hospital was associated with increased infection risk after colonization as compared with the community setting.

Conclusions

The overall infection rate after colonization with an AMR pathogen was high for most organisms, highlighting the importance of detecting colonization from both an infection control and empiric antibiotic selection perspective.

Rapid Detection of Carbapenemases Using NG-Test® CARBA 5 in Positive Blood Cultures: A Diagnostic Test Study

BACKGROUND

Infections due to carbapenem-resistant Gram-negative bacteria are emerging as an important challenge in health-care settings and a growing concern worldwide. Lateral flow immunoassay NG-Test® CARBA 5 can detect the five most reported carbapenemases (KPC, OXA-48-like, VIM, IMP, and NDM). Direct testing of positive blood cultures could reduce time to detection. This study aims to validate and report on the diagnostic yield of a novel method for carbapenemase detection in positive blood culture vials using NG-Test® CARBA 5.

METHODS

We implemented an investigator-developed method for the direct testing of positive blood cultures using NG-Test® CARBA 5. We compared results between genotypic, phenotypic, and direct NG-Test® CARBA 5 in blood.

RESULTS

A total of 32 isolates were tested (21 Enterobacterales and 11 Pseudomonas aeruginosa). Genotypic testing detected 23 carbapenemases. When comparing the results of NG-Test® CARBA 5 in blood with genotypic testing, agreement was observed in 31/32 (97%) tests. The sensitivity, specificity, positive predictive value, and negative predictive value of the NG-Test® CARBA 5 in blood were 93%, 100%, 100%, and 94%, respectively.

CONCLUSIONS

Our method using NG-Test® CARBA 5 directly in blood culture samples presented an excellent diagnostic yield when compared to genotypic profiling and permits an accurate detection of carbapenemases.

Can risk factors and risk scores help predict colonization and infection in multidrug-resistant gram-negative bacteria?

Antimicrobial resistance (AMR) is positioning as one of the most relevant threats to global public health and threatens the effective treatment of an ever-growing number of bacterial infections in various healthcare settings, particularly in acute care and surgical units, as well as in the community. Among multidrug-resistant (MDR) gram-negative bacteria (MDRGNB), Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii require special attention, since they account for most of the mortality associated with bacterial infections and are often MDR. It is clear that there is an important global variation in antibiotic resistance profiles among MDRGNB species. Extended-spectrum β-lactamase-producing Enterobacterales, carbapenem-resistant Enterobacterales, DTR-P. aeruginosa, and MDR-A. baumannii are the focus of this review. Here, we summarize a series of relevant studies on risk factors associated with colonization and infection with these MDRGNB. Likewise, we offer a comparative overview of those studies providing scoring systems to predict the risk of infection with these MDR pathogens, and their pros and cons. Despite the variable accuracy of published risk factors for predicting colonization or infection with MDRGNB, these scores are valuable tools that may help anticipate colonization and infection among those colonized. More importantly, they may help reduce unnecessary use of broad-spectrum antimicrobials and guiding the selection of an optimal treatment.

Active Surveillance of Patients Colonized with CRE: A Single-Center Study Based on a Combined Molecular/Culture Protocol

Background/Objectives: Carbapenem-resistant Enterobacteriaceae (CRE) are types of bacteria that need urgent attention globally. Active surveillance programs at hospitals are essential for the early identification of CRE carriers and the timely adoption of infection control measures. We aimed to analyze the epidemiology of CRE identified by multiplex RT-PCR in rectal swabs of patients upon admission to high-risk wards and to compare data obtained from both molecular and culture CRE screening. Methods: A total of 2861 rectal swabs, prospectively collected within 12-24 h of admission, underwent molecular screening for identification of K. pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), Verona integron-mediated metallo-β-lactamase (VIM), imipenemase (IMP), and OXA-48 (AllplexTM Entero-DR Assay). Only samples that tested positive or invalid underwent culture testing (Agar MacConkey and CHROMID® CARBA plates, bioMérieux, Craponne, France). Results: A total of 118 out of 2861 (about 4%) were positive for at least one carbapenem-resistant gene by a molecular approach (MA), with KPC, NDM, and VIM having the highest prevalence. Culture testing confirmed the presence of carbapenemase in 89 samples (75.4%), showing a disagreement rate of about 25% between the two methods, which, unfortunately, rises up to 60% for VIM. The dominant bacterial species were K. pneumoniae and E. coli (MALDI-TOF mass spectrometry). Conclusions: Our data underlined the need for the molecular screening of CRE carriers in order to implement active surveillance protocol in critical care settings and to improve infection control measures.

Epidemiology of subsequent carbapenem-resistant enterobacterales (CRE) infection among rectal carriers: A meta-analysis of incidence, risk factors and their association with geographic region and age

BACKGROUND

This study aimed to assess the incidence and risk factors of subsequent carbapenem-resistant Enterobacterales (CRE) infection among rectal carriers, and their association with geographic region and age.

METHODS

A meta-analysis of studies investigating incidence and/or risk factors of subsequent CRE infection among rectal carriers was conducted, with subgroup analyses by geographic region and age. PubMed, Embase, Web of Science, and Cochrane Library were searched (published from inception to 31 January 2024). This study is registered with PROSPERO (CRD42023444420).

RESULTS

Of 4459 studies identified, 24 studies with 8188 CRE rectal carriers were included. The pooled incidence of subsequent CRE infection was 20.6% (95% CI 15.9-25.8). The highest incidence was seen in America (23.6%, 95% CI 14.2-34.5), followed by Europe (20.9%, 95% CI 12.5-30.8) and Asia (19.8%, 95% CI 12.7-27.9). Children had a greater incidence (26.7%, 95% CI 21.3-32.3) than adults (19.8%, 95% CI 14.9-25.2). Fourteen factors were associated with subsequent CRE infection. In Asia, the most notable risk factor was gastritis (odds ratio [OR] 4.95 95% CI 1.87-13.11). In Europe, admission to the intensive care unit was prominent (OR 2.76 95% CI 1.14-6.65). In the America, the use of a urinary Foley catheter (OR 4.33 95% CI 1.06-17.70) was dominant. Admission to the intensive care unit was most notable in adults (OR 3.01 95% CI 1.80-5.02), while mechanical ventilation was shown the greatest significance in children (OR 15.61 95% CI 4.39-55.47).

CONCLUSIONS

Risk of subsequent CRE infection among rectal carriers was critical. Identifying the risk factors for subsequent infection could help in developing more potent prevention and control measures to reduce CRE infection.

Correlation between intestinal CRE colonization and consequent systemic infection in hospitalized patients in China

It is generally believed that Carbapenem-resistant Enterobacterales (CRE) colonization is primarily responsible for systemic infection in humans. However, there is no consensus on whether decolonization should be recommended in clinical practice. In China, the specific situation of CRE colonization and consequent systemic infection in hospitalized patients necessitates further exploration. We conducted a cohort study and analyzed various clinical characteristics of inpatients with intestinal CRE colonization. A risk prediction model for consequent CRE infection was established and externally validated. Our prediction model is freely available online at https://creinfection.shinyapps.io/dynnomapp/ . 839 intestinal CRE colonization samples from inpatients were included. 317 cases of intestinal CRE colonization were enrolled, 25.9% of whom developed systemic infections. The consequent CRE infection rates of Klebsiella pneumoniae and Escherichia coli were 27.0% and 32.3%. The departments at high risk for subsequent CRE infection were respiratory medicine, hematology, and intensive care unit. Secondary infection after intestinal CRE colonization in inpatients can significantly prolong the length of hospital stay (26 days vs. 33 days, P < 0.001), increase the total medical cost (144735.34￥ vs. 281852.34￥, P < 0.001), and has poor (85.11% vs. 52.44%, P < 0.001) efficacy and high mortality (5.96% vs. 18.29%, P = 0.001). Our study makes a significant contribution to comprehensively specify CRE infection, because these results can facilitate early identification of high-risk hospitalized patients, timely implementation to decolonize treatment interventions, ultimately achieve the goal of CRE nosocomial infection prevention and control.

Risk Factors Analysis and Prediction Model Establishment for Carbapenem-Resistant Enterobacteriaceae Colonization: A Retrospective Cohort Study

Purpose

The objective of this study was to identify the risk factors associated with Carbapenem-resistant Enterobacteriaceae (CRE) colonization in intensive care unit (ICU) patients and to develop a predictive risk model for CRE colonization.

Patients and Methods

In this study, 121 ICU patients from Fujian Provincial Hospital were enrolled between January 2021 and July 2022. Based on bacterial culture results from rectal and throat swabs, patients were categorized into two groups: CRE-colonized (n = 18) and non-CRE-colonized (n = 103). To address class imbalance, Synthetic Minority Over-sampling Technique (SMOTE) was applied. Statistical analyses including T-tests, Chi-square tests, and Mann-Whitney U-tests were employed to compare differences between the groups. Feature selection was performed using Lasso regression and Random Forest algorithms. A Logistic regression model was then developed to predict CRE colonization risk, and the results were presented in a nomogram.

Results

After applying SMOTE, the dataset included 198 CRE-colonized patients and 180 non-CRE-colonized patients, ensuring balanced groups. The two groups were comparable in most clinical characteristics except for diabetes, previous emergency department admission, and abdominal infection. Eight independent risk factors for CRE colonization were identified through Random Forest, Lasso regression, and Logistic regression, including Acute Physiology and Chronic Health Evaluation (APACHE) II score > 16, length of hospital stay > 31 days, female gender, previous carbapenem antibiotic exposure, skin infection, multi-site infection, immunosuppressant exposure, and tracheal intubation. The risk prediction model for CRE colonization demonstrated high accuracy (87.83%), recall rate (89.9%), precision (85.6%), and an AUC value of 0.877. Patients were categorized into low-risk (0-90 points), medium-risk (91-160 points), and high-risk (161-381 points) groups, with corresponding CRE colonization rates of 1.82%, 7.14%, and 58.33%, respectively.

Conclusion

This study identified independent risk factors for CRE colonization and developed a predictive model for assessing the risk of CRE colonization.

Risk of invasive MDRO infection in MDRO-colonized patients

OBJECTIVE

In this study, we aim to estimate the risk of developing clinical multidrug-resistant organism (MDRO) infection with carbapenem-resistant Enterobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA), or vancomycin-resistant enterococci (VRE) in colonized patients compared with non-colonized admitted to high-risk areas with a main focus on CRE colonization/infection.

DESIGN AND SETTING

Retrospective cohort study conducted at a tertiary care facility.

METHODS

This study included patients enrolled in active surveillance testing (AST) for CRE, MRSA, or VRE during the year 2021. Development of relevant invasive infection within 365 days of the AST result was collected as the primary outcome. The association between MDRO colonization and infection was calculated using the risk ratio. The prevalence of CRE organisms and carbapenemase genes is presented.

RESULTS

A total of 19,134 ASTs were included in the analysis (4,919 CRE AST, 8,303 MRSA AST, and 5,912 VRE AST). Patient demographics were similar between colonized and non-colonized groups. Colonization was associated with an increased risk of infection in the 3 cohorts (CRE, MRSA, and VRE), with risk ratios reported as 4.6, 8.2, and 22, respectively. Most patients (88%) develop CRE infection with the same colonizing carbapenemase gene. Oxa-48/NDM Klebsiella pneumoniae was the most common organism detected in CRE infection.

CONCLUSIONS

The study demonstrated that colonization with CRE, MRSA, or VRE is a risk factor for developing infections caused by the respective bacteria. The high percentage of match between carbapenemase genes detected in colonization and infection indicates that screening results might be used to inform infection management and treatment.

Efficacy and Safety of Oral Neomycin for the Decolonization of Carbapenem-Resistant Enterobacterales: An Open-Label Randomized Controlled Trial

BACKGROUND

Patients with carbapenem-resistant Enterobacterales (CRE) in the gastrointestinal (GI) tract are at risk for subsequent infections and transmission, necessitating contact precautions. Neomycin has shown in vitro activity against CRE in 66-85% of isolates. This study evaluated the efficacy and safety of neomycin for CRE decolonization.

METHODS

In this open-label randomized controlled trial, stool/rectal swab samples from high-risk patients were collected and tested for CRE colonization in the GI tract. Patients who had CRE and met eligible criteria were divided into a neomycin group (n = 26; treated with 4.2 g/day neomycin for 5 days) and a control group (n = 26). CRE detection in stool/rectal swabs was performed on days 7 ± 2 and 14 ± 2.

RESULTS

The two groups' baseline characteristics were similar. CRE presence on day 7 ± 2 was significantly lower in the neomycin group (46.2%) than in the control group (80.8%, p = 0.01). Efficacy of neomycin (4.2 g/day for 5 days) for CRE decolonization was 42.8-53.8% by day 7. By day 14 ± 2, the CRE rate in the neomycin group had risen to align with the control group's rate (73.1% vs. 61.5%, p = 0.56). The neomycin group experienced mild, temporary, gastrointestinal side-effects.

CONCLUSIONS

Neomycin effectively reduced CRE colonization on day 7 ± 2, but its impact waned by day 14 ± 2. This suggests that neomycin dosage was too low and the duration of treatment was too short for lasting CRE decolonization.

Bacterial diversity and specific taxa are associated with decolonization of carbapenemase-producing enterobacterales after fecal microbiota transplantation

OBJECTIVES

We evaluated the effect of fecal microbiota transplantation (FMT) on the clearance of carbapenemase-producing Enterobacterales (CPE) carriage.

METHODS

We performed a prospective, multi-center study, conducted among patients who received a single dose of FMT from one of four healthy donors. The primary endpoint was complete clearance of CPE carriage two weeks after FMT with a secondary endpoint at three months. Shotgun metagenomic sequencing was performed to assess gut microbiota composition of donors and recipients before and after FMT.

RESULTS

Twenty CPE-colonized patients were included in the study, where post-FMT 20% (n = 4/20) of patients met the primary endpoint and 40% (n = 8/20) of patients met the secondary endpoint. Kaplan-Meier curves between patients with FMT intervention and the control group (n = 82) revealed a similar rate of decolonization between groups. Microbiota composition analyses revealed that response to FMT was not donor-dependent. Responders had a significantly lower relative abundance of CPE species pre-FMT than non-responders, and 14 days post-FMT responders had significantly higher bacterial species richness and alpha diversity compared to non-responders (p < 0.05). Responder fecal samples were also enriched in specific species, with significantly higher relative abundances of Faecalibacterium prausnitzii, Parabacteroides distasonis, Collinsella aerofaciens, Alistipes finegoldii and Blautia_A sp900066335 (q<0.01) compared to non-responders.

CONCLUSION

FMT administration using the proposed regimen did not achieve statistical significance for complete CPE decolonization but was correlated with the relative abundance of specific bacterial taxa, including CPE species.

Prediction of Concomitant Nosocomial Infection in Patients Previously Colonized Colorectally by Multidrug-Resistant Bacteria in an SDD Setting

BACKGROUND

Antibiotic resistance is a worldwide concern. This study retrospectively analyzed patients admitted to the ICU of a tertiary hospital over a period of 7 months who were rectally colonized by multidrug-resistant microorganisms. The incidence of concomitant nosocomial infections was estimated, thus providing the risk of a colonizing microorganism producing a nosocomial infection.

METHODS

Infections with the same microorganism (concomitant) or different microorganisms (non-concomitant) were analyzed in order to adjust the empirical antibiotic treatment. Patients with rectal colonization by at least one multidrug-resistant bacterium (MDRB) on admission or after ICU admission were included. All patients had complete selective digestive decontamination (SDD) prophylaxis. For univariate analysis, categorical variables are expressed as frequencies and percentages and continuous variables as means and standard deviations, or as medians and interquartile ranges. For multivariate analysis, the model is summarized with p-values and hazard ratios with 95% confidence intervals. Survival analysis was conducted using the Kaplan-Meier method, which was performed to evaluate the time elapsed from colonization to infection by the same bacteria. Statistical significance was considered at p < 0.05.

RESULTS

Of the 130 patients with MDRB bacterial colonization analyzed, 98 remained free of infection, while 22 developed non-concomitant infections and 10 had infections concomitant to rectal colonizing bacteria. OXA-48-producing bacteria and MDR-Pseudomonas spp. incidences were 18.9% (95% CI: 7.96-35.2) and 44.4% (CI: 13.7-78.8), respectively.

CONCLUSIONS

OXA-48-producing bacteria and MDR-Pseudomonas spp. were the only bacteria associated with the development of infections concomitant to rectal colonization in an SDD setting. The incidence of MDRB infections was low.

Risk factors and molecular epidemiology of intestinal colonization by carbapenem-resistant Gram-negative bacteria in patients with hematological diseases: a multicenter case‒control study

Patients with hematological diseases are considered to be at high risk for intestinal colonization by carbapenem-resistant Gram-negative bacteria (CR-GNB). However, the epidemiological data regarding risk factors and molecular characteristics of intestinal colonized CR-GNB isolates in this population are insufficient in China. A multicenter case‒control study involving 4,641 adult patients with hematological diseases from 92 hospitals across China was conducted. Following culture of collected rectal swabs, mass spectrometry and antimicrobial susceptibility tests were performed to identify GNB species and CR phenotype. Risk factors were assessed through retrospective clinical information. Whole-genome sequencing was used to analyze the molecular characteristics of CR-GNB isolates. This trial is registered with ClinicalTrials.gov as NCT05002582. Our results demonstrated that among 4,641 adult patients, 10.8% had intestinal colonization by CR-GNB. Of these, 8.1% were colonized by carbapenem-resistant Enterobacterales (CRE), 2.6% were colonized by carbapenem-resistant Pseudomonas aeruginosa (CRPA), and 0.3% were colonized by carbapenem-resistant Acinetobacter baumannii (CRAB). The risk factors for CR-GNB colonization include male gender, acute leukemia, hematopoietic stem cell transplantation, β-lactam antibiotic usage, and the presence of non-perianal infections within 1 week. Compared with CRPA-colonized patients, patients using carbapenems were more likely to be colonized with CRE. NDM was the predominant carbapenemase in colonized CRE. This study revealed a high CR-GNB intestinal colonization rate among adult patients with hematological diseases in China, with CRE being the predominant one. Notably, a significant proportion of CRE exhibited metallo-β-lactamase production, indicating a concerning trend. These findings emphasize the importance of active screening for CR-GNB colonization in patients with hematological diseases.IMPORTANCECarbapenem-resistant Gram-negative bacteria (CR-GNB) has emerged as a significant threat to public health. Patients with hematological diseases are at high risk of CR-GNB infections due to their immunosuppressed state. CR-GNB colonization is an independent risk factor for subsequent infection. Understanding the risk factors and molecular characteristics of CR-GNB associated with intestinal colonization in patients with hematological diseases is crucial for empirical treatment, particularly in patients with febrile neutropenia. However, the epidemiology data are still insufficient, and our study aims to determine the intestinal colonization rate of CR-GNB, identify colonization risk factors, and analyze the molecular characteristics of colonized CR-GNB isolates.

A predictive score for the result of carbapenem-resistant Enterobacterales and vancomycin-resistant enterococci screening

BACKGROUND

The duration of extensively drug-resistant bacteria (XDR) carriage depends on several factors for which the information can be difficult to recover.

AIM

To determine whether past screening and clinical results of patients can predict the results of subsequent screening.

METHODS

In total, 256 patients were retrospectively included from 10 healthcare centres in France from January 2014 to January 2022. We created a predictive clearance score, ranging from -5 to +7, that included the number of XDR species and the type of resistance detected in the sample, as well as the time from the last positive sample, the number of previous consecutive negative samples, and obtaining at least one negative PCR result in the collection. This score could be used for the upcoming rectal screening of a patient carrying an XDR as soon as the last screening sample was negative.

FINDINGS

The negative predictive value was >99% for score ≤0. The median time to achieve XDR clearance was significantly shorter for a score of 0 (443 days (259-705)) than that based on previously published criteria.

CONCLUSION

This predictive score shows high performance for the assessment of XDR clearance. Relative to previous guidelines, it could help to lift specific infection prevention and control measures earlier. Nevertheless, the decision should be made according to other factors, such as antimicrobial use and adherence to hand hygiene.

Risk factors of Carbapenem-resistant Enterobacterales intestinal colonization for subsequent infections in hematological patients: a retrospective case-control study

Objective

Infections caused by Carbapenem-resistant Enterobacterales (CRE) have high treatment costs, high mortality and few effective therapeutic agents. This study aimed to determine the risk factors for progression from intestinal colonization to infection in hematological patients and the risk factors for 30-day mortality in infected patients.

Methods

A retrospective case-control study was conducted in the Department of Hematology at Shandong Provincial Hospital affiliated to Shandong First Medical University from April 2018 to April 2022. Patients who developed subsequent infections were identified as the case group by electronic medical record query of patients with a positive rectal screen for CRE colonization, and patients who did not develop subsequent infections were identified as the control group by stratified random sampling. Univariate analysis and logistic regression analysis determined risk factors for developing CRE infection and risk factors for mortality in CRE-infected patients.

Results

Eleven hematological patients in the study developed subsequent infections. The overall 30-day mortality rate for the 44 hematological patients in the case-control study was 11.4% (5/44). Mortality was higher in the case group than in the control group (36.5 vs. 3.0%, P = 0.0026), and septic shock was an independent risk factor for death (P = 0.024). Univariate analysis showed that risk factors for developing infections were non-steroidal immunosuppressants, serum albumin levels, and days of hospitalization. In multivariable logistic regression analysis, immunosuppressants [odds ratio (OR), 19.132; 95% confidence interval (CI), 1.349-271.420; P = 0.029] and serum albumin levels (OR, 0.817; 95% CI, 0.668-0.999; P = 0.049) were independent risk factors for developing infections.

Conclusion

Our findings suggest that septic shock increases mortality in CRE-infected hematological patients. Hematological patients with CRE colonization using immunosuppressive agents and reduced serum albumin are more likely to progress to CRE infection. This study may help clinicians prevent the onset of infection early and take measures to reduce mortality rates.

Inflammaging in Multidrug-Resistant Sepsis of Geriatric ICU Patients and Healthcare Challenges

Multidrug-resistant sepsis (MDR) is a pressing concern in intensive care unit (ICU) settings, specifically among geriatric patients who experience age-related immune system changes and comorbidities. The aim of this review is to explore the clinical impact of MDR sepsis in geriatric ICU patients and shed light on healthcare challenges associated with its management. We conducted a comprehensive literature search using the National Center for Biotechnology Information (NCBI) and Google Scholar search engines. Our search incorporated keywords such as "multidrug-resistant sepsis" OR "MDR sepsis", "geriatric ICU patients" OR "elderly ICU patients", and "complications", "healthcare burdens", "diagnostic challenges", and "healthcare challenges" associated with MDR sepsis in "ICU patients" and "geriatric/elderly ICU patients". This review explores the specific risk factors contributing to MDR sepsis, the complexities of diagnostic challenges, and the healthcare burden faced by elderly ICU patients. Notably, the elderly population bears a higher burden of MDR sepsis (57.5%), influenced by various factors, including comorbidities, immunosuppression, age-related immune changes, and resource-limited ICU settings. Furthermore, sepsis imposes a significant economic burden on healthcare systems, with annual costs exceeding $27 billion in the USA. These findings underscore the urgency of addressing MDR sepsis in geriatric ICU patients and the need for tailored interventions to improve outcomes and reduce healthcare costs.

Bacterial Infections in Intensive Care Units: Epidemiological and Microbiological Aspects

Intensive care units constitute a critical setting for the management of infections. The patients' fragilities and spread of multidrug-resistant microorganisms lead to relevant difficulties in the patients' care. Recent epidemiological surveys documented the Gram-negative bacteria supremacy among intensive care unit (ICU) infection aetiologies, accounting for numerous multidrug-resistant isolates. Regarding this specific setting, clinical microbiology support holds a crucial role in the definition of diagnostic algorithms. Eventually, the complete patient evaluation requires integrating local epidemiological knowledge into the best practice and the standardization of antimicrobial stewardship programs. Clinical laboratories usually receive respiratory tract and blood samples from ICU patients, which express a significant predisposition to severe infections. Therefore, conventional or rapid diagnostic workflows should be modified depending on patients' urgency and preliminary colonization data. Additionally, it is essential to complete each microbiological report with rapid phenotypic minimum inhibitory concentration (MIC) values and information about resistance markers. Microbiologists also help in the eventual integration of ultimate genome analysis techniques into complicated diagnostic workflows. Herein, we want to emphasize the role of the microbiologist in the decisional process of critical patient management.

Timing and clinical risk factors for early acquisition of gut pathogen colonization with multidrug resistant organisms in the intensive care unit

BACKGROUND

Microbiome restitution therapies are being developed to prevent gut pathogen colonization among patients in the intensive care unit (ICU) and in other select populations. If preventive therapies are to be effective, they must be administered prior to pathogen acquisition. The timing and risk factors for early acquisition of gut pathogen colonization (within 72 h) are currently unknown and could be helpful to guide ICU trial design.

METHODS

This was a prospective cohort study. Patients in the ICU had deep rectal swabs performed within 4 h of ICU admission and exactly 72 h later. Early gut pathogen colonization was classified as the new presence (based on culture of rectal swabs) of one or more of the following organisms of interest: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant (VRE), and Gram-negative bacteria that showed multidrug resistance (MDR) or third generation Cephalosporin resistance (Ceph-R). Clinical risk factors for early acquisition of gut pathogen colonization were captured using the Acute Physiology and Chronic Health Evaluation IV (APACHE IV) scoring system.

FINDINGS

Among 131 patients who were swabbed at ICU admission and 72 h later, the rates of gut pathogen colonization at ICU admission were 11.4%, 10.6%, 38.6%, and 8.3% for MRSA, VRE, MDR and Ceph-R Gram-negatives respectively. Among the patients who were negative for a given pathogen at ICU admission, the rates of early acquisition of gut pathogen colonization were 7.8% for MRSA (95% CI 3.6 to 14.2%), 7.7% for VRE (95% CI 3.6 to 14.1%), 11.3% for MDR Gram-negatives (95% CI 4.4 to 18.8%), and 4.2% for Ceph-R Gram-negatives (95% CI 1.4 to 9.5%). There were no clinical risk factors which independently predicted early acquisition of gut pathogen colonization.

INTERPRETATION

Early gut pathogen colonization was common in the ICU, but our single-center study could not identify any clinical risk factors which were significantly associated with acquisition of gut pathogens.

Evaluating indwelling devices and other risk factors for mortality in invasive Carbapenem-resistant Enterobacterales infections in Georgia, 2012-2019

Objective

Carbapenem-resistant Enterobacterales (CRE) infections are a public health threat due to the risk of transmission between patients and high associated mortality. We sought to identify risk factors for mortality in patients with invasive CRE infections and to specifically evaluate whether there was an association between indwelling medical devices and 90-day mortality.

Design

Retrospective observational cohort study of patients infected with CRE in the eight-county metropolitan Atlanta area between 2012 and 2019.

Methods

Patients with invasive CRE infections were identified via the Georgia Emerging Infections Program's active, population- and laboratory-based surveillance system and linked with the Georgia Vital Statistics database. We used bivariate analysis to identify risk factors for mortality and completed log binomial multivariable regression to estimate risk ratios (RR) for the association between indwelling devices and mortality.

Results

In total, 154 invasive CRE infections were identified, with indwelling devices present in most patients (87.7%) around the time of infection. Admission to an intensive care unit was found to be associated with 90-day mortality (adjusted RR [aRR] 1.55, 95% CI 1.07, 2.24); however, the presence of any indwelling device was not associated with increased risk of 90-day mortality in multivariable analysis (aRR 1.22, 95% CI 0.55, 2.73). Having at least two indwelling devices was associated with increased mortality (aRR 1.79, 95% CI 1.05, 3.05).

Conclusions

Indwelling devices were prevalent in our cohort but were not consistently associated with an increased risk of mortality. Further studies are needed to examine this relationship and the role of device removal.

Multicenter study on the prevalence of colonization due to carbapenem-resistant Enterobacterales strains before and during the first year of COVID-19, Italy 2018-2020

Background

Among multidrug-resistant (MDR) bacteria able to threaten human health, carbapenem-resistant Enterobacterales (CRE) have become a major public health threat globally. National and international guidelines point out the importance of active routine surveillance policies to prevent CRE transmission. Therefore, defining lines of intervention and strategies capable of containing and controlling the spread of CRE is considered determinant. CRE screening is one of the main actions to curb transmission and control outbreaks, outlining the presence and also the prevalence and types of carbapenemase enzymes circulating locally.

Objective

The purpose of this study was to outline the epidemiology of CRE colonization in Italy, detecting CRE-colonized patients at admission and during hospitalization, before and during the first year of COVID-19.

Materials and methods

A total of 11,063 patients admitted to seven different hospitals (Bologna, Catania, Florence, Genoa, Naples, Palermo, and Turin) in Intensive Care Units (ICU) and other wards (non-ICU) located in the North, Center, and South of Italy were enrolled and screened for CRE carriage at admission (T0) and during the first 3 weeks of hospitalization (T1-T3). The study spanned two periods, before (September 2018-Septemeber 2019, I observational period) and during the COVID-19 pandemic (October 2019-September 2020, II observational period).

Results

Overall, the prevalence of CRE-colonized patients at admission in ICU or in other ward, ranged from 3.9 to 11.5%, while a percentage from 5.1 to 15.5% of patients acquired CRE during hospital stay. There were large differences between the I and II period of study according to the different geographical areas and enrolling centers. Overall, comparison of prevalence of CRE-positive patients showed a significant increased trend between I and II observational periods both in ICU and non-ICU wards, mostly in the Southern participating centers. KPC-producing Klebsiella pneumoniae was the most frequent CRE species-carbapenemase combination reported in this study. In particular, the presence of KPC-producing K. pneumoniae was reported in period I during hospitalization in all the CRE-positive patients enrolled in ICU in Turin (North Italy), while in period II at admission in all the CRE-positive patients enrolled in ICU in Catania and in 58.3% of non-ICU CRE-positive patients in Naples (both centers in South Italy).

Conclusion

The prevalence of CRE in Italy highly increased during the COVID-19 pandemic, mostly in the Southern hospital centers. KPC-producing K. pneumoniae was the most frequent colonizing CRE species reported. The results of our study confirmed the crucial value of active surveillance as well as the importance of multicenter studies representing diverse geographical areas even in endemic countries. Differences in CRE colonization prevalence among centers suggest the need for diversified and center-specific interventions as well as for strengthening efforts in infection prevention and control practices and policies.

An observational study on carbapenem-resistant Enterobacterales (CRE) colonisation and subsequent risk of infection in an adult intensive care unit (ICU) at a tertiary care hospital in India

Background

Carbapenem-resistant Enterobacterales (CRE) are a global health problem with a growing prevalence. India has a high prevalence of CRE. CRE infections are difficult to treat, and are associated with significant morbidity and mortality. Colonisation is generally a prerequisite for infection and the prevention of CRE colonisation is key to the prevention of CRE infection.

Objectives

To determine the prevalence of CRE colonisation and subsequent infections in an adult intensive care unit (ICU) in India.

Methods

We conducted a prospective observational study in which perirectal swabs were obtained along with relevant clinical details of consenting adult patients upon ICU admission between January 2019 and August 2020. Rectal screening was performed using MacConkey agar plates with ertapenem disks and further identification was performed using conventional microbiological techniques. Ertapenem minimum inhibitory concentration (MIC) was determined using an epsillometer (E) test. The modified carbapenem inactivation (mCIM) test and EDTA carbapenem inactivation test (eCIM) were performed to confirm carbapenem resistance using the Clinical Laboratory Standards Institute (CLSI) 2020 guidelines.

Results

192 ICU patients were screened for CRE. 37 patients were found to be colonised with CRE. Klebsiella pneumoniae (N=25; 67.6%) was the most frequent CRE isolate, followed by Escherichia coli (N=11; 29.7%) and one Enterobacter species (N=1; 2.7%). 89.2% (33/37) patients developed CRE infection. Pneumonia was the most common CRE infection identified in 12/33 (36.4%) patients.during the hospital stay. The median duration of hospital stay was longer (17 days) for CRE colonised compared to CRE non-colonised patients (9 days) (P<0.001). Death occurred in 27 % (N=10/37) of CRE-colonised patients during the hospital admission.

Conclusion

CRE colonisation is associated with high risk of subsequent CRE infection and longer ICU and hospital admission.

High Prevalence of Carbapenem-Resistant Enterobacterales Colonization Among Intensive Care Unit Patients in a Tertiary Hospital, China

Intestinal colonization with carbapenem-resistant Enterobacterales (CRE) has been shown as a significant risk factor for subsequent CRE infections, especially in intensive care units (ICUs). The aim of this study was to determine the prevalence of intestinal CRE colonization among ICU patients in a Chinese tertiary hospital. Fecal sample screenings for CRE were performed on ICU patients weekly. Antibiotic-susceptibility profile of CRE strains was determined using the Vitek-2 analysis system and broth microdilution method. The carbapenemases of all isolates were determined by phenotypes and genotypes. Clonal relatedness was analyzed by pulsed-field gel electrophoresis (PFGE). Whole-genome sequencing was used to identify the multilocus sequence type (ST), plasmid replicons, and insertion sequences (ISs) of isolates. The overall colonization rate of CRE was 40.4% (82/203). A total of 84 CRE strains were detected, mostly with Klebsiella pneumoniae (92.9%). Antibiotic susceptibility testing profile revealed that 84 CRE strains were resistant to most antibiotics except for tigecycline and colistin. The carbapenemase-encoding genes including blaKPC-2, blaNDM-1, and blaIMP-4 were detected, and blaKPC-2 was the predominant genotype (90.8%). A total of 9 STs were identified among 84 CRE strains, and ST11 was the most common type (83.3%). A variety of mobile genetic elements, including plasmids and ISs, were detected via online tool prediction. PFGE analysis of the 78 K. pneumoniae strains showed 8 different pulsotypes, and pulsotype A was highly prevalent. This study found that the prevalence of CRE colonization was alarmingly high in the ICU, and that effective infection control measures are urgently needed to prevent the dissemination of CRE.

Colonization with extended spectrum beta-lactamase and carbapenemases producing Enterobacteriaceae among hospitalized patients at the global level: A systematic review and meta-analysis

BACKGROUND

Gut commensal bacteria can mediate resistance against pathogenic bacteria. However, exposure to antibiotics and hospitalization may facilitate the emergence of multidrug resistant bacteria. We aimed to conduct a systematic review and meta-analysis to provide comprehensive evidence about colonization rate of extended spectrum beta-lactamase and carbapenemases producing Enterobacteriaceae.

METHOD

We used PubMed, Google Scholar and Web of Science data bases to search studies from January 1, 2016 to August10, 2022 about colonization rate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae. Data were extracted from eligible studies and analyzed using Stata version 16 software. The quality of included studies was assessed using the Joanna Briggs Institute Critical Appraisal tools, and publication bias was assessed using funnel plot and eggers test.

RESULTS

We identified 342 studies from the comprehensive data search and data were extracted from 20 studies. The pooled estimate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae were 45.6%(95%CI: 34.11-57-10) and 16.19% (95% CI: 5.46-26.91) respectively. The predominant extended spectrum beta-lactamase producers were E. coli,32.99% (95% CI: 23.28-42.69) and K. pneumoniae, 11.43% (95% CI:7.98-14.89). Prolonged hospitalization was linked to carbapenemase producing Enterobacteriaceae colonization with the odds of 14.77 (95% CI: -1.35-30.90) at admission and 45.63 (95% CI: 0.86-92.12) after ≥7 days of admission.

CONCLUSION

The pooled estimate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae were high. This indicates the need for strong mitigation strategies to minimize the spread of multidrug-resistant bacteria at the healthcare facilities.

Clinical significance and burden of carbapenem-resistant Enterobacterales (CRE) colonization acquisition in hospitalized patients

BACKGROUND

Carbapenem-resistant Enterobacterales (CRE) infections have a significant morbidity and mortality toll. The clinical significance and associated burden of CRE colonization rather than infection state are not frequently investigated. We aimed to assess the outcomes of CRE colonized patients compared to matched controls.

METHODS

A secondary analysis of a 1:2 matched case-control study at a tertiary hospital in northern Israel (January-2014 to June-2017). Cases were adults who newly acquired CRE colonization during hospitalization. Controls were inpatients negatively screened for CRE, matched by age, hospitalization division and total days of hospitalization 90 days prior to screening. Our primary outcome was 1-year all-cause mortality. Secondary outcomes included 30-day mortality, diagnosis of any clinical infection, overall days of hospital stay and bloodstream infections all in 1-year follow-up. We estimated crude and propensity score weighted estimates for study outcomes.

RESULTS

We included a total of 1019 patients: 340 CRE colonized and 679 non-colonized controls. After adjustment, CRE colonization was not associated with increased 1-year mortality (weighted OR 0.98, 95% CI 0.64-1.50, p = 0.936). CRE colonized patients had 1.7 times the odds of clinical infection of any cause (weighted odds ratio (OR) 1.65, 95% CI 1.06-2.56, p = 0.025). CRE colonized patients had increased length of hospital stay compared to controls (weighted OR 1.52, 95%CI 1.10-2.10, p < 0.001) among 1-year survivors.

CONCLUSIONS

CRE colonization may not be independently associated with mortality but with higher risk of clinical infections and longer hospital stays. Infection prevention and antimicrobial stewardship are of utmost importance to prevent acquisition and infections in colonized patients.

Clinical and Molecular Characteristics of Carbapenemase-Producing E. coli Strains from Patients with Biliary System Diseases and Hematological Malignancies

Purpose

This study aims to investigate the clinical and molecular characteristics of carbapenemase-producing E. coli strains (CPECO).

Patients and Methods

We collected 38 non-repetitive CPECO strains, identified them using MALDI-TOF, and assessed their antimicrobial susceptibility via the VITEK-Compact II system. We gathered demographic and clinical patient data. Phenotypic assays were employed to detect carbapenemase types. Polymerase chain reaction (PCR) was utilized to identify the carbapenemase genes. Seven housekeeping genes were amplified and sequenced to determine the multilocus sequence typings (MLSTs).

Results

These CPECO strains, primarily isolated from aseptic site and stool screening specimens, exhibited significant resistance to most clinical antibiotics, except for tigecycline and amikacin. Most patients had underlying medical conditions and underwent invasive procedures. There were significant differences among patients concerning the presence of malignancies, digestive system disorders, endoscopic retrograde cholangiopancreatography (ERCP) surgeries and abdominal drainage tubes. However, no significant differences were observed among patients regarding conditions, including hypertension, diabetes, respiratory diseases, urinary diseases and cardiovascular diseases, as well as invasive procedures such as deep venous catheterization, endotracheal intubation and gastrointestinal catheterization. Metallo-β-lactamase was primarily responsible for carbapenem resistance, including blaNDM-5(24/38), blaNDM-1(5/38), blaNDM-9(1/38) and blaIMP-4(1/38). Additionally, 7 CPECO strains carried blaKPC-2. The distribution of CPECO sequence types (STs) was diverse, with seven strains being ST131, six strains being ST410, three strains each of ST1196 and ST10, although most STs were represented by only one strain.

Conclusion

CPECO infections in patients with biliary system diseases may result from intestinal CPECO translocation, with ERCP surgery potentially facilitating this. Meanwhile, malignant tumor was found to be a significant factor affecting CPECO infections in patients with hematological diseases. blaNDM-5, blaNDM-1 and blaNDM-9 were primarily responsible for carbapenem resistance in CPECO strains. The emergence of carbapenem-resistant ST131 and ST410 strains should be alert to prevent the spread of carbapenem-resistant genes within high-risk epidemic clones.

Nutritional drinks and enteral feeds promote the growth of carbapenemase-producing Enterobacterales in conditions that simulate disposal in hospital sinks

BACKGROUND

Studies have shown that nutritional products are discarded via handwash sinks by healthcare workers, and this practice may promote bacterial growth, including growth of pathogens such as carbapenemase-producing Enterobacterales (CPE). Outbreaks and acquisition of CPE in nosocomial settings are associated with negative outcomes for patients and hospitals.

OBJECTIVES

To investigate the potential growth-promoting effect of nutritional support drinks (NSDs) and enteral tube-feed products (ETFPs) on CPE.

METHODS

Six different CPE strains were grown in five different diluted NSDs, five different diluted ETFPs, Mueller-Hinton broth (MHB) and M9 minimal salts media to simulate discarding a small volume of nutritional product in a u-bend, already containing liquid. CPE were enumerated at 0 h, 6 h and 24 h, and compared using two-way analysis of variance and Dunett test, with confidence levels at 95%. Spearman's r was used to measure the strength of correlation between component concentrations in nutritional products and CPE growth.

RESULTS

All NSDs and ETFPs promoted CPE growth that exceeded both M9 (negative growth control) and MHB (positive growth control). In several cases, growth in NSDs/ETFPs was significantly greater compared with growth in MHB.

CONCLUSION

Nutritional products support CPE growth under in-vitro conditions. The propensity of CPE to survive in drain pipework suggests that inappropriate product disposal may further nourish established CPE in these environmental reservoirs. The growth observed in diluted NSDs and ETFPs shows that modifiable practices should be optimized to mitigate the potential risk of CPE transmission from these reservoirs.

A microbial consortium alters intestinal Pseudomonadota and antimicrobial resistance genes in individuals with recurrent Clostridioides difficile infection

Intestinal colonization with pathogens and antimicrobial-resistant organisms (AROs) is associated with increased risk of infection. Fecal microbiota transplant (FMT) has successfully been used to cure recurrent Clostridioides difficile infection (rCDI) and to decolonize intestinal AROs. However, FMT has significant practical barriers to safe and broad implementation. Microbial consortia represent a novel strategy for ARO and pathogen decolonization, with practical and safety advantages over FMT. We undertook an investigator-initiated analysis of stool samples collected from previous interventional studies of a microbial consortium, microbial ecosystem therapeutic (MET-2), and FMT for rCDI before and after treatment. Our aim was to assess whether MET-2 was associated with decreased Pseudomonadota (Proteobacteria) and antimicrobial resistance gene (ARG) burden with similar effects to FMT. Participants were selected for inclusion if baseline stool had Pseudomonadota relative abundance ≥10%. Pre- and post-treatment Pseudomonadota relative abundance, total ARGs, and obligate anaerobe and butyrate-producer relative abundances were determined by shotgun metagenomic sequencing. MET-2 administration had similar effects to FMT on microbiome outcomes. The median Pseudomonadota relative abundance decreased by four logs after MET-2 treatment, a greater decrease than that observed after FMT. Total ARGs decreased, while beneficial obligate anaerobe and butyrate-producer relative abundances increased. The observed microbiome response remained stable over 4 months post-administration for all outcomes. IMPORTANCE Overgrowth of intestinal pathogens and AROs is associated with increased risk of infection. With the rise in antimicrobial resistance, new therapeutic strategies that decrease pathogen and ARO colonization in the gut are needed. We evaluated whether a microbial consortium had similar effects to FMT on Pseudomonadota abundances and ARGs as well as obligate anaerobes and beneficial butyrate producers in individuals with high Pseudomonadota relative abundance at baseline. This study provides support for a randomized, controlled clinical trial of microbial consortia (such as MET-2) for ARO decolonization and anaerobe repletion.

Endogenous Bacteremia Caused by Intestinal Colonization of Carbapenem-Resistant Enterobacteriaceae (CRE) in Immunocompromised Children

OBJECTIVE

Carbapenem-resistant Enterobacteriaceae (CRE) infection is life-threatening, especially for immunocompromised children. The source tracking of CRE could prevent bacteremia during hospitalization. In this study, the intestinal colonization of CRE and their translocation to blood were investigated.

METHODS

Stool samples from immunocompromised pediatric patients were collected after admission, and secondary stool and blood samples were collected in case of fever. After CRE phonotypic detection, the OXA-48, NDM-1, VIM, IMP, and KPC genes were detected by PCR. Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) was used to determine the phylogenic relatedness of the blood and fecal isolates.

RESULTS

Bacteremia was recorded in 71.4% of the patients. Enterobacteriaceae spp. were recorded in 100% of the stool samples and 31% of the blood samples. The correlation between the length of stay (LOS), days of fever, chemotherapy regimens, and death rate was significant (p-value ≤ 0.05). OXA-48 was present in all CRE isolates in both the primary and the secondary stool samples and the blood samples. According to the phylogenetic data, 58.33% of the patients with bacteremia had identical blood and stool isolates. The death rate was 24.4% in children with CRE bacteremia.

CONCLUSIONS

The primary intestinal colonization with CRE in immunocompromised pediatrics and their translocation to blood was established in this study. The implementation of infection control programs and the application of infection prevention strategies for immunocompromised children is necessary.

Risk Factors for Community Colonization With Extended-Spectrum Cephalosporin-Resistant Enterobacterales (ESCrE) in Botswana: An Antibiotic Resistance in Communities and Hospitals (ARCH) Study

BACKGROUND

The epidemiology of extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in low- and middle-income countries (LMICs) is poorly described. Identifying risk factors for ESCrE colonization is critical to inform antibiotic resistance reduction strategies because colonization is typically a precursor to infection.

METHODS

From 15 January 2020 to 4 September 2020, we surveyed a random sample of clinic patients at 6 sites in Botswana. We also invited each enrolled participant to refer up to 3 adults and children. All participants had rectal swabs collected that were inoculated onto chromogenic media followed by confirmatory testing. Data were collected on demographics, comorbidities, antibiotic use, healthcare exposures, travel, and farm and animal contact. Participants with ESCrE colonization (cases) were compared with noncolonized participants (controls) to identify risk factors for ESCrE colonization using bivariable, stratified, and multivariable analyses.

RESULTS

A total of 2000 participants were enrolled. There were 959 (48.0%) clinic participants, 477 (23.9%) adult community participants, and 564 (28.2%) child community participants. The median (interquartile range) age was 30 (12-41) and 1463 (73%) were women. There were 555 cases and 1445 controls (ie, 27.8% of participants were ESCrE colonized). Independent risk factors (adjusted odds ratio [95% confidence interval]) for ESCrE included healthcare exposure (1.37 [1.08-1.73]), foreign travel [1.98 (1.04-3.77]), tending livestock (1.34 [1.03-1.73]), and presence of an ESCrE-colonized household member (1.57 [1.08-2.27]).

CONCLUSIONS

Our results suggest healthcare exposure may be important in driving ESCrE. The strong links to livestock exposure and household member ESCrE colonization highlight the potential role of common exposure or household transmission. These findings are critical to inform strategies to curb further emergence of ESCrE in LMICs.

Active surveillance for carbapenem resistant enterobacteriaceae (CRE) using stool cultures as a method to decrease CRE infections in the pediatric intensive care unit (PICU)

BACKGROUND

The incidence of Carbapenem Resistant Enterobacteriaceae (CRE) infections is increasing worldwide. Due to dearth of alternative antibiotics, prevention of infection transmission is a part of CRE infection management strategy. Early detection of CRE by active surveillance coupled with contact isolation is much more appropriate compared to contact isolation upon receipt of routine cultures dictated by the patient's clinical condition.

OBJECTIVES

To determine whether active CRE surveillance will decrease CRE infection rates in the Pediatric Intensive Care Unit (PICU).

METHODS

Retrospective observational study done in the 10-bed PICU of a tertiary care teaching children's hospital from July 2013 to June 2015. Rectal swabs for CRE were sent from all PICU patients except stable post-operative patients. Contact isolation precautions were followed for rectal swab positive patients. CRE colonization and infection rates were calculated and compared.

RESULTS

Total of 1262 rectal swabs were sent from 1022 patients. CRE colonization rate was 19.5%. Post intervention, ICU acquired CRE colonization decreased by 36% and ICU acquired CRE infection rates decreased by 100%, both showed significant decrease (p ​< ​0.0001).

CONCLUSION

Active CRE surveillance and institution of contact isolation in appropriate situations is helpful in decreasing CRE colonization and infection rates in the PICU.

The role of plasmids in carbapenem resistant E. coli in Alameda County, California

BACKGROUND

Antimicrobial resistant infections continue to be a leading global public health crisis. Mobile genetic elements, such as plasmids, have been shown to play a major role in the dissemination of antimicrobial resistance (AMR) genes. Despite its ongoing threat to human health, surveillance of AMR in the United States is often limited to phenotypic resistance. Genomic analyses are important to better understand the underlying resistance mechanisms, assess risk, and implement appropriate prevention strategies. This study aimed to investigate the extent of plasmid mediated antimicrobial resistance that can be inferred from short read sequences of carbapenem resistant E. coli (CR-Ec) in Alameda County, California. E. coli isolates from healthcare locations in Alameda County were sequenced using an Illumina MiSeq and assembled with Unicycler. Genomes were categorized according to predefined multilocus sequence typing (MLST) and core genome multilocus sequence typing (cgMLST) schemes. Resistance genes were identified and corresponding contigs were predicted to be plasmid-borne or chromosome-borne using two bioinformatic tools (MOB-suite and mlplasmids).

RESULTS

Among 82 of CR-Ec identified between 2017 and 2019, twenty-five sequence types (STs) were detected. ST131 was the most prominent (n = 17) followed closely by ST405 (n = 12). bla_CTX-M were the most common ESBL genes and just over half (18/30) of these genes were predicted to be plasmid-borne by both MOB-suite and mlplasmids. Three genetically related groups of E. coli isolates were identified with cgMLST. One of the groups contained an isolate with a chromosome-borne bla_CTX-M-15 gene and an isolate with a plasmid-borne bla_CTX-M-15 gene.

CONCLUSIONS

This study provides insights into the dominant clonal groups driving carbapenem resistant E. coli infections in Alameda County, CA, USA clinical sites and highlights the relevance of whole-genome sequencing in routine local genomic surveillance. The finding of multi-drug resistant plasmids harboring high-risk resistance genes is of concern as it indicates a risk of dissemination to previously susceptible clonal groups, potentially complicating clinical and public health intervention.

Epidemiology and Risk Factors of Carbapenemase-Producing Enterobacteriaceae Acquisition and Colonization at a Korean Hospital over 1 Year

Background: Carbapenemase-producing Enterobacteriaceae (CPE) are known to be primarily responsible for the increasing spread of carbapenem-resistant Enterobacteriaceae and have therefore been targeted for preventing transmission and appropriate treatment. This study aimed to describe the clinical and epidemiological characteristics and risk factors of CPE infection in terms of acquisition and colonization. Methods: We examined patients' hospital data, including active screening on patients' admission and in intensive care units (ICUs). We identified risk factors for CPE acquisition by comparing the clinical and epidemiological data of CPE-positive patients between colonization and acquisition groups. Results: A total of 77 CPE patients were included (51 colonized and 26 acquired). The most frequent Enterobacteriaceae species was Klebsiella pneumoniae. Among CPE-colonized patients, 80.4% had a hospitalization history within 3 months. CPE acquisition was significantly associated with treatment in an ICU [adjusted odds ratio (aOR): 46.72, 95% confidence interval (CI): 5.08-430.09] and holding a gastrointestinal tube (aOR: 12.70, 95% CI: 2.61-61.84). Conclusions: CPE acquisition was significantly associated with ICU stay, open wounds, holding catheters or tubes, and antibiotic treatment. Active CPE screening should be implemented on admission and periodically for high-risk patients.

Gut microbiota alterations in critically Ill patients with carbapenem-resistant Enterobacteriaceae colonization: A clinical analysis

Background

Carbapenem-resistant Enterobacteriaceae (CRE) are an emerging concern for global health and are associated with high morbidity and mortality in critically ill patients. Risk factors for CRE acquisition include broad-spectrum antibiotic use and microbiota dysbiosis in critically ill patients. Therefore, we evaluated the alteration of the intestinal microbiota associated with CRE colonization in critically ill patients.

Methods

Fecal samples of 41 patients who were diagnosed with septic shock or respiratory failure were collected after their admission to the intensive care unit (ICU). The gut microbiota profile determined using 16S rRNA gene sequencing and quantitative measurement of fecal short-chain fatty acids were evaluated in CRE-positive (n = 9) and CRE negative (n = 32) patients. The analysis of bacterial metabolic abundance to identify an association between CRE acquisition and metabolic pathway was performed.

Results

CRE carriers showed a significantly increased proportion of the phyla Proteobacteria and decreased numbers of the phyla Bacteroidetes as compared to the CRE non-carriers. Linear discriminant analysis (LDA) with linear discriminant effect size showed that the genera Erwinia, Citrobacter, Klebsiella, Cronobacter, Kluyvera, Dysgomonas, Pantoea, and Alistipes had an upper 2 LDA score in CRE carriers. The alpha-diversity indices were significantly decreased in CRE carriers, and beta-diversity analysis demonstrated that the two groups were clustered significantly apart. Among short-chain fatty acids, the levels of isobutyric acid and valeric acid were significantly decreased in CRE carriers. Furthermore, the PICRUSt-predicted metabolic pathways revealed significant differences in five features, including ATP-binding cassette transporters, phosphotransferase systems, sphingolipid metabolism, other glycan degradation, and microbial metabolism, in diverse environments between the two groups.

Conclusion

Critically ill patients with CRE have a distinctive gut microbiota composition and community structure, altered short-chain fatty acid production and changes in the metabolic pathways. Further studies are needed to determine whether amino acids supplementation improves microbiota dysbiosis in patients with CRE.

Off-label use versus formal recommendations of conventional and novel antibiotics for the treatment of infections caused by multidrug-resistant bacteria

The infections caused by multidrug- and extensively drug-resistant (MDR, XDR) bacteria, including Gram-positive cocci (GPC, including methicillin-resistant Staphylococcus aureus, MDR-Streptococcus pneumoniae and vancomycin-resistant enterococci) and Gram-negative bacilli (GNB, including carbapenem-resistant [CR] Enterobacterales, CR-Pseudomonas aeruginosa and XDR/CR-Acinetobacter baumannii complex) can be quite challenging for physicians with respect to treatment decisions. Apart from complicated urinary tract and intra-abdominal infections (cUTIs, cIAIs), bloodstream infections and pneumonia, these difficult-to-treat bacteria also cause infections at miscellaneous sites (bones, joints, native/prosthetic valves and skin structures, etc.). Antibiotics like dalbavancin, oritavancin, telavancin and daptomycin are currently approved for the treatment of acute bacterial skin and skin structural infections (ABSSSIs) caused by GPC. Additionally, ceftaroline, linezolid and tigecycline have been formally approved for the treatment of community-acquired pneumonia and ABSSSI. Cefiderocol and meropenem-vaborbactam are currently approved for the treatment of cUTIs caused by XDR-GNB. The spectra of ceftazidime-avibactam and imipenem/cilastatin-relebactam are broader than that of ceftolozane-tazobactam, but these three antibiotics are currently approved for the treatment of hospital-acquired pneumonia, cIAIs and cUTIs caused by MDR-GNB. Clinical investigations of other novel antibiotics (including cefepime-zidebactam, aztreonam-avibactam and sulbactam-durlobactam) for the treatment of various infections are ongoing. Nevertheless, evidence for adequate antibiotic regimens against osteomyelitis, arthritis and infective endocarditis due to several GPC and MDR-GNB is still mostly lacking. A comprehensive review of PubMed publications was undertaken and the formal indications and off-label use of important conventional and novel antibiotics against MDR/XDR-GPC and GNB isolates cultured from miscellaneous sites are presented in this paper.

Risk Factors for Carbapenem-Resistant Enterobacterales Clinical Treatment Failure

The Centers for Disease Control and Prevention (CDC) categorized carbapenem-resistant Enterobacterales (CRE) infections as an "urgent" health care threat requiring public attention and research. Certain patients with CRE infections may be at higher risk for poor clinical outcomes than others. Evidence on risk or protective factors for CRE infections are warranted in order to determine the most at-risk populations, especially with newer beta-lactam/beta-lactamase inhibitor (BL/BLI) antibiotics available to treat CRE. We aimed to identify specific variables involved in CRE treatment that are associated with clinical failure (either 30-day mortality, 30-day microbiologic recurrence, or clinical worsening/failure to improve throughout antibiotic treatment). We conducted a retrospective, observational cohort study of hospitalized patients with CRE infection sampled from 2010 to 2020 at two medical systems in Detroit, Michigan. Patients were included if they were ≥18 years old and culture positive for an organism in the Enterobacterales order causing clinical infection with in vitro resistance by Clinical and Laboratory Standards Institute (CLSI) breakpoints to at least one carbapenem. Overall, there were 140 confirmed CRE infections of which 39% had clinical failure. The most common infection sources were respiratory (38%), urinary (20%), intra-abdominal (16%), and primary bacteremia (14%). A multivariable logistic regression model was developed to identify statistically significant associated predictors with clinical failure, and they included Sequential Organ Failure Assessment (SOFA) score (adjusted odds ratio [aOR], 1.18; 95% confidence interval [CI], 1.06 to 1.32), chronic dialysis (aOR, 5.86; 95% CI, 1.51-22.7), and Klebsiella pneumoniae in index culture (aOR, 3.09; 95% CI, 1.28 to 7.47). Further research on CRE infections is needed to identify best practices to promote treatment success. IMPORTANCE This work compares carbapenem-resistant Enterobacterales (CRE) infections using patient, clinical, and treatment variables to understand which characteristics are associated with the highest risk of clinical failure. Knowing which risk factors are associated with CRE infection failure can provide clinicians better prognostic and targeted interventions. Research can also further investigate why certain risk factors cause more clinical failure and can help develop treatment strategies to mitigate associated risk factors.

Impact of Multidisciplinary Collaborative Intervention on Isolation Implementation in Prevention and Control of Multi-drug Resistance Infection

OBJECTIVE

Contact precautions, especially the initiation of isolation, are important measures to prevent and control multidrug-resistant organisms (MDROs). However, the implementation in clinical practice remains weak. This study aimed to analyze the impact of multidisciplinary collaborative intervention on isolation implementation in multidrug-resistant infection, and determine the factors that affect the implementation of isolation measures.

METHODS

A multidisciplinary collaborative intervention related to isolation was conducted at a teaching tertiary hospital in central China on November 1, 2018. The information of 1338 patients with MDRO infection and colonization at 10 months before and after the intervention was collected. Then, the issuance of isolation orders was retrospectively analyzed. Univariate analysis and multivariate logistic regression analysis were performed to analyze the factors that affected the isolation implementation.

RESULTS

The overall issuance rate of isolation orders was 61.21%, which increased from 33.12% to 75.88% (P<0.001) after the implementation of the multidisciplinary collaborative intervention. The intervention (P<0.001, OR=0.166) was a promoting factor for the issuance of isolation orders, in addition to the length of stay (P=0.004, OR=0.991), department (P=0.004), and microorganism (P=0.038).

CONCLUSION

The isolation implementation remains far lower than policy standards. Multidisciplinary collaborative interventions can effectively improve the compliance to isolation measures implemented by doctors, thereby promoting the standardized management of MDROs, and providing reference for further improving the quality of hospital infection management.

Epidemiology and Mortality Analysis Related to Carbapenem-Resistant Enterobacterales in Patients After Admission to Intensive Care Units: An Observational Study

Purpose

The prevalence of carbapenem-resistant Enterobacterales (CRE) is rapidly increasing worldwide. Patients in the intensive care unit (ICU) are susceptible to CRE infections, and the related mortality rate is increased. It is necessary to understand CRE strains and risk factors for CRE infection in the ICU, to facilitate development of effective prophylactic strategies and treatments for ICU patients.

Patients and Methods

This observational study was conducted in a tertiary hospital between 2016 and 2021. The subjects were patients with CRE cultured from specimens obtained after ICU admission. Genotypes of strains of CRE and carbapenemase-producing Enterobacterales (CPE) were identified, CRE infection was distinguished from mere colonization, and the clinical course of these patients was investigated.

Results

Among 327 CRE cases, 84 (25.7%) showed infection and 243 (74.3%) showed colonization. Of these patients, 138 (42.2%) died. The CRE strains were Klebsiella pneumoniae (253 cases, 77.4%), Enterobacter cloacae (44 cases, 13.5%), and Escherichia coli (15 cases, 4.6%). Among CRE cases, CPE was found in 249 (76.1%), including Klebsiella pneumoniae carbapenemase (KPC) in 164 (65.9%), and Guiana extended-spectrum (GES) in 64 (25.7%). A bedridden state, longer ICU stay, chronic kidney disease, malignancy, connective tissue disease, ICU admission for cardiac arrest, and CRE infection were associated with higher mortality, but cerebrovascular disease and ICU admission for trauma were associated with lower mortality. GES outbreak was caused by person-to-person transmission and was controlled through active surveillance.

Conclusion

The frequency of K. pneumoniae and KPC was the highest, but E. cloacae and GES was characteristically high in this study. Active CRE surveillance can be helpful for controlling outbreak.

A Visualized Mortality Prediction Score Model in Hematological Malignancies Patients with Carbapenem-Resistant Organisms Bloodstream Infection

Background

Bloodstream infection (BSI) due to carbapenem-resistant organisms (CROs) has emerged as a worldwide problem associated with high mortality. This study aimed to evaluate the risk factors associated with mortality in HM patients with CROs BSI and to establish a scoring model for early mortality prediction.

Methods

We conducted a retrospective cohort study at our hematological department from January 2018 to December 2021, including all HM patients with CROs BSI. The outcome measured was death within 30-day of BSI onset. Survivor and non-survivor subgroups were compared to identify predictors of mortality. Univariate and multivariate Cox regression analyses were used to identify prognostic risk factors and develop a nomogram.

Results

In total, 150 HM patients were included in the study showing an overall 30-day mortality rate of 56%. Klebsiella pneumonia was the dominant episode. Cox regression analysis showed that pre-infection length of stay was >14 days (score 41), Pitt score >4 (score 100), mucositis (score 41), CAR (The ratio of C-reactive protein to albumin) >8.8 (score 57), early definitive therapy (score 44), and long-duration (score 78) were positive independent risk predictors associated with 30-day mortality, all of which were selected into the nomogram. Furthermore, all patients were divided into the high-risk group (≥160 points) or the low-risk group based on the prediction score model. The mortality of the high-risk group was 8 times more than the low-risk group. Kaplan-Meier analysis showed that empirical polymyxin B therapy was associated with a lower 30-day mortality rate, which was identified as a good prognostic factor in the high-risk group. In comparison, empirical carbapenems and tigecycline were poor prognostic factors in a low-risk group.

Conclusion

Our score model can accurately predict 30-day mortality in HM patients with CROs BSI. Early administration of CROs-targeted therapy in the high-risk group is strongly recommended to decrease mortality.

Development of a Risk Prediction Model of Subsequent Bloodstream Infection After Carbapenem-Resistant Enterobacteriaceae Isolated from Perianal Swabs in Hematological Patients

Purpose

Patients with hematological diseases are at high risk of carbapenem-resistant Enterobacteriaceae (CRE) infection, and CRE-related bloodstream infection (BSI) is associated with high mortality risk. Therefore, developing a predictive risk model for subsequent BSI in hematological patients with CRE isolated from perianal swabs could be used to guide preventive strategies.

Methods

This was a single-center retrospective cohort study at a tertiary blood diseases hospital, including all hematological patients hospitalized from 10 October 2017 to 31 July 2021. We developed a predictive model using multivariable logistic regression and internally validated it using enhanced bootstrap resampling.

Results

Of 421 included patients with CRE isolated from perianal swabs, BSI due to CRE occurred in 59. According to the multivariate logistic analysis, age (OR[odds ratio]=1.04, 95% CI[confidence interval]: 1.01-1.06, P=0.004), both meropenem and imipenem minimal inhibitory concentration (MIC) of the isolate from perianal swabs>8ug/mL (OR=5.34, 95% CI: 2.63-11.5, P<0.001), gastrointestinal symptoms (OR=3.67, 95% CI: 1.82-7.58, P<0.001), valley absolute neutrophil count (10⁹/L)>0.025 (OR=0.07, 95% CI: (0.02-0.19, P<0.001) and shaking chills at peak temperature (OR=6.94, 95% CI: (2.60-19.2, P<0.001) were independently associated with CRE BSI within 30 days and included in the prediction model. At a cut-off of prediction probability ≥ 21.5% the model exhibited a sensitivity, specificity, positive predictive value and negative predictive value of 79.7%, 85.6%, 96.27% and 47.47%. The discrimination and calibration of the prediction model were good on the derivation data (C-statistics=0.8898; Brier score=0.079) and enhanced bootstrapped validation dataset (adjusted C-statistics=0.881; adjusted Brier score=0.083). The risk prediction model is freely available as a mobile application at https://liujia1992.shinyapps.io/dynnomapp/.

Conclusion

A prediction model based on age, meropenem and imipenem MIC of isolate, gastrointestinal symptoms, valley absolute neutrophil count and shaking chills may be used to better inform interventions in hematological patients with CRE isolated from perianal swabs.

Clinical Risk Factors and Microbiological and Intestinal Characteristics of Carbapenemase-Producing Enterobacteriaceae Colonization and Subsequent Infection

Gastrointestinal colonization with carbapenem-resistant Enterobacteriaceae (CRE) is always a prerequisite for the development of translocated infections. Here, we sought to screen for fecal carriage of CRE and identify the risk factors for CRE colonization as well as subsequent translocated pneumonia in critically ill patients admitted to the intensive care unit (ICU) of a university hospital in China. We further focused on the intestinal flora composition and fecal metabolic profiles in CRE rectal colonization and translocated infection patients. Animal models of gastrointestinal colonization with a carbapenemase-producing Klebsiella pneumoniae (carbapenem-resistant K. pneumoniae [CRKP]) clinical isolate expressing green fluorescent protein (GFP) were established, and systemic infection was subsequently traced using an in vivo imaging system (IVIS). The intestinal barrier, inflammatory factors, and infiltrating immune cells were further investigated. In this study, we screened 54 patients hospitalized in the ICU with CRE rectal colonization, and 50% of the colonized patients developed CRE-associated pneumonia, in line with the significantly high mortality rate. Upon multivariate analysis, risk factors associated with subsequent pneumonia caused by CRE in patients with fecal colonization included enteral feeding and carbapenem exposure. Furthermore, CRKP colonization and translocated infection influenced the diversity and community composition of the intestinal microbiome. Downregulated propionate and butyrate probably play important and multiangle roles in regulating immune cell infiltration, inflammatory factor expression, and mucus and intestinal epithelial barrier integrity. Although the risk factors and intestinal biomarkers for subsequent infections among CRE-colonized patients were explored, further work is needed to elucidate the complicated mechanisms. IMPORTANCE Carbapenem-resistant Enterobacteriaceae have emerged as a major threat to modern medicine, and the spread of carbapenem-resistant Enterobacteriaceae is a clinical and public health problem. Gastrointestinal colonization by potential pathogens is always a prerequisite for the development of translocated infections, and there is a growing need to assess clinical risk factors and microbiological and intestinal characteristics to prevent the development of clinical infection by carbapenem-resistant Enterobacteriaceae.

Poor outcomes in both infection and colonization with carbapenem-resistant Enterobacterales

OBJECTIVES

To describe the epidemiology of patients with nonintestinal carbapenem-resistant Enterobacterales (CRE) colonization and to compare clinical outcomes of these patients to those with CRE infection.

DESIGN

A secondary analysis of Consortium on Resistance Against Carbapenems in Klebsiella and other Enterobacteriaceae 2 (CRACKLE-2), a prospective observational cohort.

SETTING

A total of 49 US short-term acute-care hospitals.

PATIENTS

Patients hospitalized with CRE isolated from clinical cultures, April, 30, 2016, through August 31, 2017.

METHODS

We described characteristics of patients in CRACKLE-2 with nonintestinal CRE colonization and assessed the impact of site of colonization on clinical outcomes. We then compared outcomes of patients defined as having nonintestinal CRE colonization to all those defined as having infection. The primary outcome was a desirability of outcome ranking (DOOR) at 30 days. Secondary outcomes were 30-day mortality and 90-day readmission.

RESULTS

Of 547 patients with nonintestinal CRE colonization, 275 (50%) were from the urinary tract, 201 (37%) were from the respiratory tract, and 71 (13%) were from a wound. Patients with urinary tract colonization were more likely to have a more desirable clinical outcome at 30 days than those with respiratory tract colonization, with a DOOR probability of better outcome of 61% (95% confidence interval [CI], 53%-71%). When compared to 255 patients with CRE infection, patients with CRE colonization had a similar overall clinical outcome, as well as 30-day mortality and 90-day readmission rates when analyzed in aggregate or by culture site. Sensitivity analyses demonstrated similar results using different definitions of infection.

CONCLUSIONS

Patients with nonintestinal CRE colonization had outcomes similar to those with CRE infection. Clinical outcomes may be influenced more by culture site than classification as "colonized" or "infected."