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

Validation of a rapid molecular detection test for gram-negative multidrug-resistant bacteria in rectal swabs upon admission of patients to the intensive care unit

In ICU settings, screening patients upon admission for potential multiresistant bacteria (BMR) carriers is crucial. Traditionally, clinical decisions relied on delayed culture results, but a rapid PCR molecular test called RealCycler-Rezero-U/G (Progenie-molecular©), emerged as an alternative. This study aimed to validate its effectiveness in detecting gram-negative BMR in rectal swabs at ICU admission. Over 24 months, an observational study was conducted on 1,234 admitted patients, with 217 meeting isolation criteria and undergoing both PCR and culture tests. Results showed a 17.5 % positive rate for screening. The PCR test exhibited impressive accuracy at 98.6 % and a strong negative predictive value of 99.4 %. The area under the ROC curve (AUC) was 0.98, indicating high reliability. Notably, PCR results were available 44.5 h earlier than culture. In conclusion, PCR-based molecular testing for gram-negative BMR offers excellent diagnostic performance and a valuable negative predictive value, making it a suitable screening tool for ICU admissions.

Burden of severe infections due to carbapenem-resistant pathogens in intensive care unit

Intensive care units (ICU) for various reasons, including the increasing age of admitted patients, comorbidities, and increasingly complex surgical procedures (e.g., transplants), have become "the epicenter" of nosocomial infections, these are characterized by the presence of multidrug-resistant organisms (MDROs) as the cause of infection. Therefore, the perfect match of fragile patients and MDROs, as the cause of infection, makes ICU mortality very high. Furthermore, carbapenems were considered for years as last-resort antibiotics for the treatment of infections caused by MDROs; unfortunately, nowadays carbapenem resistance, mainly among Gram-negative pathogens, is a matter of the highest concern for worldwide public health. This comprehensive review aims to outline the problem from the intensivist's perspective, focusing on the new definition and epidemiology of the most common carbapenem-resistant MDROs (Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacterales) to emphasize the importance of the problem that must be permeating clinicians dealing with these diseases.

Five-Hour Detection of Intestinal Colonization with Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae Using the β-Lacta Phenotypic Test: the BLESSED Study

Extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-PE) intestinal colonization is of particular concern as it negatively impacts morbidity and is the main source of external cross-contamination in hospitalized patients. Contact isolation strategies may be caught out due to the turnaround time needed by laboratories to report intestinal colonization, during which patients may be inappropriately isolated or not isolated. Here, we developed a protocol combining enrichment by a rapid selective subculture of rectal swab medium and realization of a β-Lacta test on the obtained bacterial pellet (named the BLESSED protocol). The performances of this protocol were validated in vitro on 12 ESBL-PE strains spiked into calibrated sample suspensions and confirmed in clinical settings using 155 rectal swabs, of which 23 (reference method) and 31 (postenrichment broth culture) came from ESBL-PE carriers. In vitro, the protocol detected, with 100% sensitivity, the presence of the 12 ESBL-PE strains from 104 CFU/mL. In the clinical validation cohort, 22 out of the 23 (reference method) and 28 out of the 31 (postenrichment broth culture) ESBL-PE-positive rectal samples were accurately detected. The diagnostic performances for ESBL-PE detection, considering all ESBL-PE carriers, were 90% sensitivity, 98% specificity, an 87% positive predictive value, and a 98% negative predictive value. Our protocol is a rapid and low-cost method that can detect intestinal colonization with ESBL-PE in less than 5 h more accurately than the reference method, opening the field for further studies assessing a rapid and targeted isolation strategy applied only to patients with a positive BLESSED protocol result. IMPORTANCE To both improve the efficiency of contact isolation among ESBL-PE carriers and avoid the unnecessary isolation of noncolonized patients, we should reduce the turnaround time of ESBL screening in laboratories and improve the sensitivity of diagnostic methods. The development of rapid and low-cost methods that satisfy these two goals is a promising approach. In this study, we developed such a technique and report its good diagnostic performance, opening the door for further studies assessing a rapid and targeted isolation strategy applied in a few hours only for patients truly colonized with ESBL-producing bacteria.

Screening for Antimicrobial-Resistant Gram-negative bacteria in hospitalised patients, and risk of progression from colonisation to infection: Systematic review

BACKGROUND

Transmission of antimicrobial-resistant Gram-negative bacteria (AMR-GNB) among hospitalised patients can lead to new cases of carriage, infection and outbreaks, hence the need for early carrier identification. We aim to explore two key elements that may guide control policies for colonisation/infection in hospital settings: screening practices on admission to hospital wards and risk of developing infection from colonisation.

METHODS

We searched on PubMed, Scopus and Cochrane databases for studies published from 2010 up to 2021 reporting on adult patients hospitalised in high-income countries.

RESULTS

The search retrieved 11853 articles. After screening, 100 studies were included. Combining target patient groups and setting type, we identified six screening approaches. The most reported approach was all admitted patients to high-risk (HR) wards (49.4%). The overall prevalence of AMR-GNB was 13.8% (95%CI 9.3-19.0) with significant differences across regions and time. Risk of progression to infection among colonised patients was 11.0% (95%CI 8.0-14.3) and varied according to setting and pathogens' group (p value<0.0001), with higher values reported for Klebsiella species (18.1%; 95%CI 8.9-29.3).

CONCLUSIONS

While providing a comprehensive overview of the screening approaches, our study underlines the considerable burden of AMR-GNB colonisation and risk of progression to infection in hospitals by pathogen, setting and time.

Overview of the actions to combat bacterial resistance in large hospitals

OBJECTIVE

to analyze, in the clinical practice of large hospitals, how the adoption of measures to prevent and control the spread of bacterial resistance has occurred, and to propose a score for the institutions' adherence.

METHOD

a cross-sectional study carried out in 30 large hospitals of Minas Gerais, from February 2018 to April 2019, after approval by the Ethics and Research Committee. Interviews were conducted with hospital managers, with Hospital Infection Control Services coordinators, and with the care coordinators of the Inpatient Units and Intensive Care Center. In addition, observations were made of the adoption of preventive measures by the multidisciplinary team in the care units.

RESULTS

in the 30 participating hospitals, 93.3% (N=28) had protocols for prophylactic antibiotics, and 86.7% (N=26) performed their audit, 86.7% (N=26) for therapeutic antibiotics and 83.3% (N=25) their audit; 93.3% (N=56) used gloves and cloaks for patients in contact precautions, and 78.3% (N=47) of the professionals were unaware of or answered incompletely on the five moments for hand hygiene. In the score to identify the adoption of measures to control bacterial resistance, 83.3% (N=25) of the hospitals were classified as partially compliant, 13.3% (N=04) as deficient, and 3.4% (N=01) as non-adoption.

CONCLUSION

it was found that the recommended measures to contain bacterial resistance are not consolidated in the clinical practice of the hospitals.

Screening for Intestinal Carriage of Extended-spectrum Beta-lactamase-producing Enterobacteriaceae in Critically Ill Patients: Expected Benefits and Evidence-based Controversies

The rising burden of intensive care unit (ICU)-acquired infections due to extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) strengthens the requirement for efficient prevention strategies. The detection of intestinal carriage of ESBL-E through active surveillance cultures (ASC) and the implementation of contact precautions (CP) in carriers are currently advocated in most high-income countries, to prevent cross-transmission and subsequent ESBL-E infections in critically-ill patients. Yet, recent studies have challenged the benefit of ASC and CP in controlling the spread of ESBL-E in ICUs with high compliance to standard hygiene precautions and no ongoing outbreak of ESBL-producing Klebsiella pneumoniae or Enterobacter spp. Besides, given their debated performance to positively predict which patients are at risk of ESBL-E infections, ASC results appear of limited value to rationalize the empirical use of carbapenems in the ICU, emphasizing the urgent need for novel anticipatory and diagnostic approaches. This Viewpoint article summarizes the available evidence on these issues.

Role of surveillance cultures in infection control

Hospital-acquired infections are a known menace to the primary disease, for which a patient is admitted. These infections are twenty times more common in developing countries than in the developed ones. Surveillance for colonised patients can be passive or active process. In many hospitals, active surveillance culture for certain sentinel organisms followed by contact precautions for the same is an important part of infection control policy. Specific measures can be taken on early detection of multidrug-resistant organism, allowing prevention of widespread transmission in hospitals. Cultures are the most conventional and economical microbiological method of detection. The cost of active surveillance is a major challenge, especially for developing nations. These nations lack basic infrastructure and have logistic issues. The guidelines regarding this are not very clearly delineated for developing countries. Each hospital has its own challenges and the process is to be tailor-made accordingly. The following review delineates the various aspects of active surveillance for the colonisation of various organisms and the advantages and disadvantages of the same.

Cohorting for preventing the nosocomial spread of Carbapenemase-Producing Enterobacterales, in non-epidemic settings: is it mandatory?

BACKGROUND

Worldwide dissemination of Carbapenemase-Producing Enterobacterales (CPE) has led to national and international guidance recommending the implementation of cohorting in healthcare settings (HS). However, in view of recent data regarding the spread of Extended-spectrum Beta-lactamase-producing Enterobacterales, we may wonder about the usefulness of this measure in a non-outbreak settings; here, individual contact isolation may be sufficient to control the risk of dissemination.

AIM/METHODS

We conducted a narrative review of the literature and discussed the role of cohorting.

FINDINGS

CPE are responsible for outbreaks in HS, which are considered the epicentre of spread of resistance strains. CPE are responsible for adverse effects such as increases in hospital stay and costs, less therapeutic options and thus higher risk of clinical failures and mortality. Environment and materials have also been described contaminated with CPE and can be the source of outbreak. Even if guidelines and publications have supported implementation of cohorting, there are no randomized studies demonstrating the mandatory nature of this measure. Most studies are descriptive and cohorting is usually one of several other measures to control outbreaks. Cohorting is not adapted to all HS, which requires human and material resources. Other measures must be strengthened such as compliance of hand hygiene, antibiotic stewardship and surveillance of contact patients. Individual risk factors of acquisition should also be evaluated.

CONCLUSION

Local epidemiology and resources must be assessed before implementing cohorting.

The Rising Problem of Multidrug-Resistant Organisms in Intensive Care Units

Because of antimicrobial overuse and misuse, the issue of multidrug-resistant organisms has been increasingly significant. Multidrug-resistant organism infection is of extreme concern in critical care patients. Infections with these organisms are difficult to treat because of the elevated rate of antimicrobial therapy failure. Such infections are linked to high mortality, poor prognosis, prolonged hospital stays, and increased medical expenses. Nineteen percent of patients with intensive care unit stays of greater than 24 hours acquire infections. Critically ill patients have risk factors that make them susceptible to infections. Critical care nurses must implement infection prevention interventions. Infection control strategies can be categorized as vertical or horizontal. Vertical approaches target a single pathogen; horizontal approaches are nonspecific. Infection control practice compliance is vital to prevent transmission of multidrug-resistant organisms through cross-contamination. This article discusses the severity of multidrug-resistant organism infection, risk factors, and infection prevention strategies in critical care settings.

Validation of a carbapenem-resistant Enterobacteriaceae colonization risk prediction model: A retrospective cohort study in Korean intensive care units

BACKGROUND

To assess the external validity of a carbapenem-resistant Enterobacteriaceae colonization risk prediction model (CREP-model).

METHODS

This retrospective cohort study included 414 patients admitted to the intensive care units of a tertiary hospital from November 1, 2017 to May 31, 2018. Data were collected via medical record review, and we analyzed the performance of the CREP-model by assessment of calibration, discrimination, clinical usefulness, and uniformity-of-fit.

RESULTS

The validation subjects showed differences in age, Acute Physiology and Chronic Health Evaluation II score, mechanical ventilation days, and carbapenem-resistant Enterobacteriaceae colonization rate from those of the CREP-model development subjects. The calibration-in-the-large was 0.069 (95% confidence interval [CI], 0.065-0.074), and calibration slope was 1.114 (95% CI, 1.091-1.136). The area under the receiver operating characteristic curve was 0.883 (95% CI, 0.838-0.928). At the predicted risk of 0.25, the sensitivity, specificity, and correct classification rates were 81.3%, 79.8%, and 80.0%, respectively, and the net benefit according to the model was 0.035 with 64 fewer false-positive results per 100 patients. The calibration, discrimination, and clinical usefulness showed similar results among subjects stratified according to sex, age group, medical department, and admission source.

CONCLUSIONS

The CREP-model showed good performance in the validation sample; therefore, we recommend introducing the CREP-model into intensive care units of tertiary hospitals to improve decision-making.

Is systematic fecal carriage screening of extended-spectrum beta-lactamase-producing Enterobacteriaceae still useful in intensive care unit: a systematic review

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are disseminating worldwide leading to increased hospital length of stay and mortality in intensive care units (ICU). ESBL-E dissemination was first due to outbreaks in hospital settings which led to the implementation of systematic fecal carriage screening to improve hygiene procedures by contact precautions. ESBLs have since spread in the community, and the relevance of contact precautions is questioned. ESBL-E dissemination led to an overuse of carbapenems triggering the emergence of carbapenem-resistant Enterobacteriaceae. Empirical antimicrobial therapy based on ESBL-E fecal carriage has been proposed but is debated as it could increase the consumption of carbapenems among ESBL-E carriers without any clinical benefit. Finally, selective decontamination among ESBL-E fecal carriers is evoked to decrease the risk for subsequent ESBL-E infection, but its efficacy remains debated. We propose to systematically review the evidence to recommend or not such systematic ESBL-E fecal carriage screening in adult ICU.

METHODS

Every article focusing on ESBL-E and ICU available on the MEDLINE database was assessed. Articles were included if focusing on cross-transmission, efficacy of hygiene procedures, link between ESBL-E colonization and infection or guidance of empirical therapy or selective decontamination efficacy.

RESULTS

Among 330 articles referenced on PubMed, 39 abstracts were selected for full-text assessment and 25 studies were included. Systematic screening of ESBL-E fecal carriage to guide contact precautions do not seem to decrease the rate of ESBL-E cross-transmission. It has a very good negative predictive value for subsequent ESBL-E infections but a positive predictive value between 40 and 50% and so does not help to spare carbapenems. Cessation of ESBL-E carriage systematic screening could decrease the use of carbapenems in ICU without any clinical harm. Nevertheless, further studies are needed to validate these results from monocentric before-after study. Selective decontamination strategy applied to ESBL-E fecal carriers could be helpful, but available data are conflicting.

CONCLUSION

Current knowledge lacks of high-quality evidence to strongly recommend in favor of or against a systematic ESBL-E fecal carriage screening policy for ICU patients in a non-outbreak situation. Further evaluation of selective decontamination or fecal microbiota transplantation among ESBL-E fecal carriers is needed.

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

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Adherence to contact precautions by different types of healthcare workers through video monitoring in a tertiary hospital

BACKGROUND

Contact precautions are required to prevent transmission of multi-drug-resistant organisms; however, reports on adherence rates vary. This study used video monitoring to evaluate adherence to the use of personal protective equipment (PPE) by different types of healthcare workers.

METHODS

This observational study was conducted in a 781-bed tertiary hospital from July 2016 to March 2017. Cameras were installed in areas where staff don PPE. Infection control teams observed the videos and assessed adherence rates.

RESULTS

In total, 1097 opportunities for donning PPE were observed. Most staff observed were nurses and nursing assistants (Ns/Nsas) (880/1097, 80.2%). Overall, the adherence rate to appropriate PPE use was 34.0%. The adherence rate among Ns/Nsas was lower (239/858, 27.9%) compared with infectious disease doctors (18/18, 100%) and cleaning staff (42/49, 85.7%). The adherence rate for PPE use for Clostridium difficile infection (CDI) with toxin detection was significantly higher than that for CDI without toxin detection and multi-drug-resistant organisms (P<0.001 for both). The adherence rate for patients with an independent functional status was higher than that for patients with a dependent functional status (P=0.018). The adherence rate was lower in the intensive care unit (ICU) than in non-ICU wards (27.6% vs 36.5%; P=0.006).

CONCLUSION

Video monitoring is a useful tool for monitoring adherence to PPE use, facilitating observation of more PPE opportunities than direct observation. Adherence to contact precautions varied by occupation; however, overall adherence was insufficient. The lower adherence rate in nurses might be due to more frequent care visits.