Risk Factors for Bloodstream Infections Due to ESBL-Producing Escherichia coli, Klebsiella spp., and Proteus mirabilis

Use of a rapid detection test for extended-spectrum beta-lactamase from direct blood culture: an antimicrobial stewardship tool in a tertiary hospital in Spain

INTRODUCTION

Bacteremia caused by Gram-negative bacilli places a substantial burden on healthcare systems, mainly due to antibiotic resistance and delays in administering appropriate antimicrobial treatment (AT). The aim of this study was to describe the implementation of a rapid detection test (RDT) for CTX-M Extended Spectrum Beta-Lactamase-producing Enterobacterales (ESBL-PE) bacteremia as a tool for Antimicrobial Stewardship (AMS) in a tertiary hospital in Spain.

MATERIAL AND METHODS

A cross-sectional study was conducted on blood culture (BC) samples from adult patients (≥18 years) admitted to a tertiary hospital in Spain (January 2021-February 2024). BCs with confirmed Enterobacterales identification were included. An RDT was used to detect CTX-M ESBL from direct BC. The results were reported to the AMS team. Data from electronic medical records and our laboratory information system were analyzed to explore the utility of implementing an RDT as an AMS tool.

RESULTS

A total of 250 BCs from 250 patients were included. Empiric antimicrobial treatment (EAT) had not been prescribed in 41/250 (16.4%) patients, but was appropriately initiated in 33/250 (13.2%) after notification of the RDT results. Among those already receiving EAT (209/250, 83.6%), inappropriate and appropriate actions in AT were observed in 18/250 (7.2%) and 191/250 (76.4%) patients, respectively. By the time routine AST results were available, 241 (96.4%) patients had received appropriate treatment.

CONCLUSIONS

This study demonstrated the real-world application of an RDT to detect CTX-M ESBL directly from BC in a tertiary hospital. Early reporting of CTX-M ESBL status in Enterobacterales bacteremia enabled physicians and AMS teams to optimize AT.

Klebsiella pneumoniae species complex bloodstream infection in adult patients: changing epidemiology and determinants of poor outcomes

PURPOSE

Klebsiella pneumoniae is a common cause of hospital- and community-acquired infection and can readily acquire multiple antimicrobial resistance determinants leading to poor health outcomes. We define the contemporary burden of disease, risk factors for antimicrobial resistance, and poor health outcomes for patients with K. pneumoniae bloodstream infection (Kp-BSI).

METHODS

All blood cultures with growth of K. pneumoniae species complex among residents of Queensland, Australia (population ≈ 5 million) who received care through a public hospital were identified over a 20-year period. Clinical, microbiological and outcome information was obtained from state-wide databases.

RESULTS

A total of 6, 988 patients (7, 496 episodes) with incident Kp-BSI were identified. Incidence rate more than doubled from 5.8 cases to 12.2 cases per 100,000 population over the study period (4.5% rise per year). 258 (3.4%) episodes involved isolates resistant to third-generation cephalosporins (3GC-R). 3GC-R Kp-BSI crude incidence rate increased almost 10% each year. The proportion of hospital-onset episodes reduced from 49.1 to 35.0%. Of all Kp-BSI episodes, 864 (11.5%) died within 30-days. A lower respiratory tract source was associated with a high risk of death (aHR 1.68, 95% CI 1.30-2.16) while a urinary tract source a lower risk (aHR 0.48, 95% CI 0.35-0.66). 3GC-R Kp-BSI was not related to death (aHR 1.08, 95% CI 0.76-1.50).

CONCLUSION

A rising burden of both Kp-BSI and 3GC-R blood isolates in a previous low-prevalence setting is concerning. A significant rise in community-onset Kp-BSI over the 20-year period was noteworthy and requires further evaluation. 3GC-R status was not associated with mortality.

Is It Time to Start Worrying? A Comprehensive Report on the Three-Year Prevalence of ESBL-Producing Bacteria and Their Trends in Antibiotic Resistance from the Largest University Hospital in Slovakia

BACKGROUND/OBJECTIVES

Over the past few decades, extended-spectrum β-lactamase (ESBL)-producing bacteria have become a great concern in healthcare systems worldwide, imposing large burdens by increasing antimicrobial resistance and patient morbidity. Given the high mortality rates and emergence of multidrug-resistant (MDR) strains, monitoring ESBL prevalence and resistance patterns is crucial. This study aimed to evaluate ESBL-producing Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae over three years, focusing on phenotypic distribution and resistance profiles.

METHODS

A total of 1599 ESBL-producing bacterial samples were collected and analysed. A panel of 20 antibiotics was tested to determine resistance traits. Data were recorded on phenotypical distribution, isolation types, changes in antibiotic resistance, and the relation of such changes to antibiotic consumption (defined daily dose) from clinical isolates.

RESULTS

Phenotypical analysis revealed the minimal presence of the Cefotaximase from Munich (CTX-M) phenotype in E. coli and K. pneumoniae, creating a distinct epidemiological profile compared to global patterns. Shifts in isolation trends, particularly in P. mirabilis, suggest an expected increase in associated-mortality-rate in the coming years. While resistance trends were not statistically significant, MDR and extensively drug-resistant (XDR) strains were identified across all three bacteria. Only meropenem showed consistent 100% efficacy against E. coli, with other antibiotics displaying only partial effectiveness.

CONCLUSIONS

These findings highlight the need for ongoing surveillance of ESBL-producing bacteria and underscore challenges in managing antibiotic resistance due to limited efficacy of last-resort treatments. The unique phenotypical distribution observed could impact local resistance management strategies in hospital settings in the coming years.

Management of Chronic Neuromuscular Respiratory Failure in the Intensive Care Unit

In this seminar we describe the critical care management of patients with chronic neuromuscular diseases (cNMD). Determination of the acuity of the critical illness and trajectory of illness in the setting of cNMD is necessary to guide decision making. Systemic complications of critical illness, cardiac support needs, and peri-intubation considerations may be affected by underlying diagnosis. Mechanical ventilatory support, whether noninvasive or invasive, requires redefinition of the goals of ventilation on a patient-by-patient basis. Mode and approach to invasive ventilation and liberation to noninvasive ventilation versus tracheostomy have limited evidence, but potential clinical approaches are reviewed.

CTX-M, TEM, and SHV Genes in Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp Isolated from Hematologic Cancer Patients with Bacteremia in Uganda

Purpose

We determined the phenotypic resistance to third-generation cephalosporins, phenotypic extended spectrum beta-lactamase (ESBL) prevalence, and genotypic prevalence of ESBL-encoding genes blaCTX-M, blaTEM, and blaSHV in Enterobacteriaceae isolated from hematologic cancer patients with febrile neutropenia and bacteremia at the Uganda Cancer Institute (UCI).

Patients and Methods

Blood cultures from hematologic cancer patients with febrile neutropenia were processed in BACTEC 9120. E. coli, K. pneumoniae, and Enterobacter spp. isolates were identified using conventional biochemical methods. Antimicrobial susceptibility tests, phenotypic ESBL characterization, and genotypic characterization of the ESBL-encoding genes blaCTX-M, blaTEM, and blaSHV were determined for pure isolates of E. coli, K. pneumoniae, and Enterobacter spp.

Results

Two hundred and two patients were included in the study. Median age of patients was 19 years (IQR: 10-30 years). Majority (N=119, 59%) were male patients. Sixty (30%) of the participants had at least one febrile episode due to Enterobacteriaceae. Eighty-three organisms were isolated with E. coli being predominant (45, 54%). Seventy-nine (95%) Enterobacteriaceae were multidrug resistant. The ESBL phenotype was detected in 54/73 (74%) of Enterobacteriaceae that were resistant to third-generation cephalosporins. A higher proportion of Enterobacteriaceae with ESBL-positive phenotype were resistant to piperacillin-tazobactam (p=0.024), gentamicin (p=0.000), ciprofloxacin (p=0.000), and cotrimoxazole (p=0.000) compared to Enterobacteriaceae, which were sensitive to third-generation cephalosporins. The organisms were more susceptible to carbapenems and chloramphenicol than resistant. ESBL-encoding genes (blaCTX-M, blaTEM, and blaSHV) were detected in 55 (75%) of the 73 Enterobacteriaceae that were resistant to third-generation cephalosporins. BlaCTX-M, was the most common ESBL-encoding gene identified with 50 (91%).

Conclusion

ESBL-producing Enterobacteriaceae are a predominant cause of bacteremia in hematologic cancer patients at UCI. The most common ESBL-encoding gene identified in the ESBL-PE was blaCTX-M. Resistance to imipenem and meropenem was low.

Evaluating the Impact of Source-specific Order Sets for Sepsis on Empiric Antibiotic Selection in the Emergency Department

This retrospective cohort study found that implementing source-specific antibiotic order sets for sepsis in the emergency department increased appropriate empiric antibiotic selection from 51% to 74% (P = .01).

ESBL and carbapenemase-producing Enterobacteriaceae in infectious pleural effusions: current epidemiology at Hôpital du Mali

Background

Antimicrobial resistance (AMR) is a global health concern, with extended-spectrum β-lactamases (ESBLs) and carbapenemases being major contributors. Pleural infection (PI) is a severe condition in West Africa, complicated by AMR. This study aimed to investigate the prevalence and molecular characteristics of ESBL and carbapenemase-producing enterobacteria in pleural effusions in Mali.

Materials and methods

Pleural fluid samples from 526 patients with pleuritis were analyzed. Enterobacterial species were isolated and identified, and the prevalence of resistance genes (blaOXA-48, blaNDM-1, blaKPC, blaTEM, blaSHV) and virulence factors was determined.

Results

Among the patients, 110 were diagnosed with enterobacterial pleuritis. Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis were the main pathogens identified. Resistance to β-lactams and cephalosporins was high, while carbapenems showed good activity. ESBL production was detected in 33.6% of isolates, with blaTEM being the most common gene. Carbapenemase gene (blaNDM-1) was found in three isolates.

Conclusion

The study highlights the high prevalence of multidrug-resistant bacteria and the need for appropriate antibiotic selection based on local resistance patterns. Understanding the molecular characteristics of resistance is crucial for optimizing patient care and developing effective therapeutic strategies. Further research is needed to monitor and control AMR in PIs in Mali.