Control of extended-spectrum β-lactamase-producing Enterobacteriaceae nosocomial acquisition in an intensive care unit: A time series regression analysis

A clinical prediction tool for extended-spectrum β-lactamase-producing Enterobacteriaceae urinary tract infection

Background

Prevalence of extended-spectrum beta-lactamase-producing-Enterobacteriaceae (ESBL-E) has risen in patients with urinary tract infections. The objective of this study was to determine explore the risk factors of ESBL-E infection in hospitalized patients and establish a predictive model.

Methods

This retrospective study included all patients with an Enterobacteriaceae-positive urine sample at the first affiliated hospital of Jinan university from January 2018 to December 2019. Antimicrobial susceptibility patterns of ESBL-E were analyzed, and multivariate analysis of related factors was performed. From these, a nomogram was established to predict the possibility of ESBL-E infection. Simultaneously, susceptibility testing of a broad array of carbapenem antibiotics was performed on ESBL-E cultures to explore possible alternative treatment options.

Results

Of the total 874 patients with urinary tract infections (UTIs), 272 (31.1%) were ESBL-E positive. In the predictive analysis, five variables were identified as independent risk factors for ESBL-E infection: male gender (OR = 1.607, 95% CI 1.066–2.416), older age (OR = 4.100, 95% CI 1.678–12.343), a hospital stay in preceding 3 months (OR = 1.872, 95% CI 1.141–3.067), invasive urological procedure (OR = 1.810, 95% CI 1.197–2.729), and antibiotic use within the previous 3 months (OR = 1.833, 95% CI 1.055–3.188). In multivariate analysis, the data set was divided into a training set of 611 patients and a validation set of 263 patients The model developed to predict ESBL-E infection was effective, with the AuROC of 0.650 (95% CI 0.577–0.725). Among the antibiotics tested, several showed very high effectiveness against ESBL-E: amikacin (85.7%), carbapenems (83.8%), tigecycline (97.1%) and polymyxin (98.2%).

Conclusions

The nomogram is useful for estimating a UTI patient’s likelihood of infection with ESBL-E. It could improve clinical decision making and enable more efficient empirical treatment. Empirical treatment may be informed by the results of the antibiotic susceptibility testing.

Extended spectrum beta-lactamase producing Enterobacterales faecal carriage in a medical intensive care unit: low rates of cross-transmission and infection

Background

Extended-spectrum beta-lactamases-producing Enterobacterales (ESBL-E) are disseminating worldwide especially in Intensive Care Units (ICUs) and are responsible for increased health costs and mortality. The aims of this work were to study ESBL-E dissemination in ICU and to assess the impact of ESBL-E fecal carriage on subsequent infections during a non-outbreak situation.

Methods

We therefore screened every patient at admission then once a week in a medical ICU between January and June 2015. Each ESBL-E isolate was characterized by ESBL genes PCR amplification and the clonal dissemination was assessed by Pulsed-Field Gel Electrophoresis (PFGE).

Results

Among the 608 screened patients, 55 (9%) were colonized by ESBL-E. Forty-four isolates were available for further analysis. Most of them (43/44, 98%) contained a ESBL gene from the CTX-M group. Only one case of ESBL-E cross-transmission occurred, even for acquired ESBL-E colonization. Subsequent infection by ESBL-E occurred in 6/55 (11%) patients and infecting ESBL-E strains were the colonizing ones. ESBL-E faecal carriage had a negative predictive value of 100% and a positive predictive value of 40% to predict ESBL-E ventilator associated-pneumonia (VAP). Alternatives to carbapenems consisting in piperacillin-tazobactam, ceftolozane-tazobactam and ceftazidime-avibactam were all active on this panel of ESBL-E.

Conclusions

ESBL-E expansion and acquisition in ICU in a non-outbreak situation are not any more fully explained by cross-transmission. Mechanisms underlying ESBL-E dissemination in ICU are still to investigate. Interestingly, as far as we know, our study demonstrates for the first time by PFGE that the colonizing strain is indeed the infecting one in case of subsequent ESBL-E infection. Nevertheless, subsequent ESBL-E infection remains a rare event conferring poor positive predictive value for ESBL-E colonization to predict ESBL-E VAP. Relevance of systematic ESBL-E faecal screening at ICU admission and during ICU stay needs further investigation.

Infections Caused by Extended-Spectrum β-Lactamase Producing Escherichia Coli in Systemic Lupus Erythematosus Patients: Prevalence, Risk Factors, and Predictive Model

Objective

To investigate the prevalence and risk factors of infections caused by Extended-Spectrum β-Lactamase (ESBL) producing Escherichia coli (E. coli) in systemic lupus erythematosus (SLE) patients and develop a predictive model.

Methods

Three hundred and eighty-four consecutive SLE patients with E. coli infection were enrolled in this retrospective case control study from January 2012 to December 2017. Prevalence and antimicrobial susceptibility pattern of ESBL producing E. coli were analyzed. Multivariate analysis was performed to determine the risk factors. Sensitivity and specificity were obtained at various point cutoffs and area under the receiver operator characteristic curve (AuROC) was determined to confirm the prediction power of the model.

Results

Of the total 384 E. coli strains tested, 212 (55.2%) produced ESBL. The majority of these isolates were from urine (44.3%). Carbapenems (>80%) and amikacin (89.6%) had good activity against ESBL producing E. coli. Eleven variables were identified as independent risk factors for ESBL producing E. coli infection including Enterobacteriaceae colonization or infection in preceding year (OR=8.15, 95%CI 5.12-21.71), daily prednisone dose > 30mg (OR=5.48, 95%CI 3.12-13.72), low C3 levels (OR=2.17, 95%CI 1.62-6.71), nosocomial acquired infection (OR=4.12, 95%CI 1.98-8.85), etc. The model developed to predict ESBL producing E. coli infection was effective, with the AuROC of 0.840 (95% CI 0.799-0.876).

Conclusions

The prevalence of ESBL producing E. coli was increasing with high antibiotics resistance in patients with SLE. The model revealed excellent predictive performance and exhibited a good discrimination.

Differential molecular approach and ESBL detection from Klebsiella pneumoniae and Escherichia coli isolated from the supraglottic region of patients undergoing mechanical ventilation in an intensive care unit

Introduction: Given their ability for colonizing the supraglottic region, desiccation tolerance, resistance to β-lactam antibiotics, and adherence to both inert surfaces and epithelial cells, Klebsiella pneumoniae and Escherichia coli are potentially pathogenic microorganisms for patients undergoing mechanical ventilation in an intensive care unit (ICU).Objective: To perform a molecular characterization and detection of extended spectrum β-lactamases (ESBL) in K. pneumoniae and E. coli strains isolated from the supraglottic region of patients undergoing mechanical ventilation in an ICU.Materials and methods: A descriptive study was conducted in 18 isolates. Disk diffusion technique was used for detecting ESBL-producing bacteria. Molecular characterization was made by BOX-PCR technique, while ESBL production was confirmed by testing the isolates against cefotaxime and ceftazidime, alone and in combination with clavulanic acid.Results: a K. pneumoniae strain and another E. coli strain were confirmed as ESBL producers. A divergence greater than 50% was observed in most of the strains; besides non-infectious origin strains resistant to third generation cephalosporins were found.Conclusion: The polyclonality found in this study might indicate that most of the strains belong to each patient’s microbiota.

Prevention and Control of Multidrug-Resistant Gram-Negative Bacteria in Adult Intensive Care Units: A Systematic Review and Network Meta-analysis

Background

This study evaluated the relative efficacy of strategies for the prevention of multidrug-resistant gram-negative bacteria (MDR-GNB) in adult intensive care units (ICUs).

Methods

A systematic review and network meta-analysis was performed; searches of the Cochrane Library, PubMed, Embase, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) included all randomized controlled trials and observational studies conducted in adult patients hospitalized in ICUs and evaluating standard care (STD), antimicrobial stewardship program (ASP), environmental cleaning (ENV), decolonization methods (DCL), or source control (SCT), simultaneously. The primary outcomes were MDR-GNB acquisition, colonization, and infection; secondary outcome was ICU mortality.

Results

Of 3805 publications retrieved, 42 met inclusion criteria (5 randomized controlled trials and 37 observational studies), involving 62068 patients (median age, 58.8 years; median APACHE [Acute Physiology and Chronic Health Evaluation] II score, 18.9). The majority of studies reported extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and MDR Acinetobacter baumannii. Compared with STD, a 4-component strategy composed of STD, ASP, ENV, and SCT was the most effective intervention (rate ratio [RR], 0.05 [95% confidence interval {CI}, .01-.38]). When ENV was added to STD+ASP or SCT was added to STD+ENV, there was a significant reduction in the acquisition of MDR A. baumannii (RR, 0.28 [95% CI, .18-.43] and 0.48 [95% CI, .35-.66], respectively). Strategies with ASP as a core component showed a statistically significant reduction the acquisition of ESBL-producing Enterobacteriaceae (RR, 0.28 [95% CI, .11-.69] for STD+ASP+ENV and 0.23 [95% CI, .07-.80] for STD+ASP+DCL).

Conclusions

A 4-component strategy was the most effective intervention to prevent MDR-GNB acquisition. As some strategies were differential for certain bacteria, our study highlighted the need for further evaluation of the most effective prevention strategies.

Impact of Discontinuing Contact Precautions for MRSA and ESBLE in an Intensive Care Unit: A Prospective Noninferiority Before and After Study

OBJECTIVE

To compare incidence densities of methicillin-resistant Staphylococcus aureus (MRSA) or extended-spectrum β-lactamase–producing Enterobacteriaceae (ESBLE) acquisition in the intensive care unit (ICU) before and after discontinuation of contact precautions (CP) and application of standard precautions (SP).

DESIGN

Prospective noninferiority before-and-after study comparing 2 periods: January 1, 2012, to January 31, 2014 (the CP period) and February 1, 2014, to February 29, 2016 (the SP period).

SETTING

A 16-bed polyvalent ICU in France with only single-bed rooms with dedicated equipment and reusable medical devices.

PATIENTS

All patients admitted to the ICU during the CP and SP periods were included: 1,547 and 1,577 patients, respectively.

METHODS

Incidence densities of ICU-acquired MRSA or ESBLE were determined per 1,000 patient days. Other studied factors included (1) patient characteristics, (2) incidence densities of MRSA or ESBLE carried at admission, (3) compliance with hand hygiene protocols, and (4) antibiotic consumption.

RESULTS

Incidence densities of ICU-acquired MRSA were 0.82 (95% confidence interval [CI], 0.31–1.33) and 0.79 (95% CI, 0.30–1.29) per 1,000 patient days during the CP and SP periods, respectively. For ESBLE, values were 2.7 (95% CI, 1.78–3.62) and 2.06 (95% CI, 1.27–2.86) per 1,000 patient days. These rates were significantly nonsuperior during the SP period compared to CP period, with a margin of 1 per 1,000 patient days for both MRSA (P=.002) and ESBLE (P=.004). Other factors were comparable during the 2 periods. Only ESBLE carried at admission was inferior during the SP period. We observed a high level of compliance to hand hygiene protocols.

CONCLUSIONS

Discontinuing CP did not increase acquired MRSA and ESBLE in our ICU with single rooms with dedicated equipment, strict application of hand hygiene, medical and paramedical leadership, and good antibiotic stewardship.

Infect Control Hosp Epidemiol 2017;38:1342–1350