Neonatal sepsis with meningitis, ventriculitis and brain abscess caused by Edwardsiella tarda.

A case of neonatal sepsis caused by Edwardsiella tarda, an uncommon pathogen typically associated with aquatic lifeforms, is described. The infant presented in septic shock with seizures and respiratory failure and was found to have meningitis, ventriculitis and a brain abscess requiring drainage. Only a small number of case reports of neonatal E. tarda infection, several with sepsis with poor auditory or neurodevelopmental outcomes or meningitis, have been described in the literature. This case report suggests that E. tarda, while uncommon, can be a cause of serious central nervous system disease in the neonatal population and that an aggressive approach to pursuing and treating complications may lead to improved neurodevelopmental outcomes.

A practical approach to screening for carbapenemase-producing Enterobacterales- views of a group of multidisciplinary experts from English hospitals.

INTRODUCTION: Carbapenemase-producing Enterobacterales (CPE) are an important public health threat, with costly operational and economic consequences for NHS Integrated Care Systems and NHS Trusts. UK Health Security Agency guidelines recommend that Trusts use locally developed risk assessments to accurately identify high-risk individuals for screening, and implement the most appropriate method of testing, but this presents many challenges. METHODS: A convenience sample of cross-specialty experts from across England met to discuss the barriers and practical solutions to implementing UK Health Security Agency framework into operational and clinical workflows. The group derived responses to six key questions that are frequently asked about screening for CPE. KEY FINDINGS: Four patient groups were identified for CPE screening: high-risk unplanned admissions, high-risk elective admissions, patients in high-risk units, and known positive contacts. Rapid molecular testing is a preferred screening method for some of these settings, offering faster turnaround times and more accurate results than culture-based testing. It is important to stimulate action now, as several lessons can be learnt from screening during the COVID-19 pandemic, as well as from CPE outbreaks. CONCLUSION: Further decisive and instructive information is needed to establish CPE screening protocols based on local epidemiology and risk factors. Local management should continually evaluate local epidemiology, analysing data and undertaking frequent prevalence studies to understand risks, and prepare resources- such as upscaled screening- to prevent increasing prevalence, clusters or outbreaks. Rapid molecular-based methods will be a crucial part of these considerations, as they can reduce unnecessary isolation and opportunity costs.

Abdominal abscess caused by Raoultella ornithinolytica secondary to postoperative gastric fistula: case report and review of literature.

BACKGROUND: In recent years, Raoultella ornithinolytica (R. ornithinolytica) have attracted clinical attention as a new type of pathogen. A wide range of infections with these germs is reported, and commonly found in urinary tract infections, respiratory infections, and bacteremia. CASE PRESENTATION: We report the case of an elderly woman with liver abscess, choledocholithiasis and cholangitis, who developed gastric fistula and abdominal abscess after underwent choledocholithotomy, and R. ornithinolytica were isolated from the abdominal drainage fluid. The patient was treated with meropenem and levofloxacin and had a good outcome. CONCLUSIONS: To the best of our knowledge, case of isolating R. ornithinolytica from a patient with non-viscerally abdominal abscess was extremely rare. We share a case of a woman with non-viscerally abdominal abscess secondary to postoperative gastric fistula, R. ornithinolytica was isolated from the patient's pus, and the pathogenic bacteria may originate from the gastrointestinal tract. Based on this case, We should be cautious that invasive treatment may greatly increase the probability of infection with this pathogenic bacterium.

Comparison of clinical outcomes of patients with serial negative surveillance cultures according to a subsequent polymerase chain reaction test for carbapenemase-producing Enterobacterales.

BACKGROUND: Carbapenemase-producing Enterobacterales (CPE) are of serious concern worldwide due to high morbidity and mortality. AIM: To evaluate the impact of the result of a subsequent polymerase chain reaction (PCR) test for carbapenemase after serial negative surveillance cultures on positive culture conversion in patients with three consecutive negative surveillance cultures for CPE, and to identify risk factors for conversion. METHODS: A retrospective study of patients with positive CPE cultures on CHROMagar KPC medium was performed in a Korean tertiary hospital from October 2018 to December 2022. PCR for blaKPC, blaNDM, blaIMP, blaVIM, blaGES, and blaOXA-48 was performed after three consecutive negative rectal swab cultures. Clinical characteristics and outcomes of patients were compared according to whether follow-up PCR was positive (CNPP) or negative (CNPN). FINDINGS: Of 1075 patients with positive CPE cultures, 150 (14.0%) yielded three consecutive negative rectal swab cultures. Of these, 50 (33.3%) were CNPP, and 100 (66.7%) were CNPN. Risk factors associated with a positive PCR result on multivariate analysis were: age, central venous catheter, and Escherichia coli infection. CNPP patients were more likely to have positive culture conversion for CPE than CNPN patients (39/44 (88.6%) vs 21/50 (42.0%), P<0.001). In multivariate analysis, independent risk factors for culture conversion were: a positive PCR result after surveillance cultures, diabetes mellitus, central venous catheter, and Klebsiella pneumoniae. CONCLUSION: CNPP patients have higher rates of culture conversion than CNPN patients, and a follow-up PCR test after serial negative surveillance cultures is useful in deciding whether or not to discontinue contact precautions.

Clinical performance evaluation of TAQPATH Enteric Bacterial Select Panel for the detection of common enteric bacterial pathogens in comparison to routine stool culture and other qPCR-based diagnostic tests.

IMPORTANCE: Enteric bacterial infections caused by Salmonella, Shigella, pathogenic Escherichia coli, and Campylobacter represent one of the most common causes of infectious enteritis worldwide. The timely and accurate diagnosis of pathogens causing gastroenteritis is crucial for patient care, public health, and disease surveillance. While stool culture has long been the standard and highly specific method for detecting enteric pathogens, it is labor-intensive and time-consuming with limited sensitivity. To improve patient outcomes, there is a need to implement new cost-effective approaches for the detection of bacterial enteric pathogens with higher sensitivity and faster time to result. This study shows that multiplex real-time polymerase chain reaction-based tests, such as the TAQPATH Enteric Bacterial Select Panel, are accurate and cost-effective diagnostic alternatives for the detection and differentiation of the most common enteric bacterial pathogens, offering quicker time to result and higher sensitivity compared to routine stool culture.

Evaluation of the French novel disc diffusion-based algorithm for the phenotypic screening of carbapenemase-producing Enterobacterales.

OBJECTIVES: The early identification of carbapenemase-producing Enterobacterales (CPE) is required to prevent their spread and initiate proper therapy. Accordingly, it is crucial to develop efficient algorithms using susceptibility testing results to discriminate non-carbapenemase producers (non-CPE) from those that require complementary tests. In 2022, to adapt its recommendations to the evolution of CPE epidemiology (increased prevalence of OXA-244 producers), the Antibiogram Committee of the French Society of Microbiology (CA-SFM) proposed a new algorithm for the screening of CPE. We compared this algorithm to the former algorithm (2015-2021). METHODS: From July 2022 to January 2023, all nonduplicate enterobacterial isolates referred to French National Reference Centre for carbapenemase detection (n = 518) were subjected to the former CA-SFM algorithm (2015 to 2021) using inhibition diameters of ertapenem, ticarcillin-clavulanate, temocillin and meropenem or imipenem, and the novel CA-SFM algorithm (since 2022) using inhibition diameters of ceftazidime-avibactam, temocillin, and meropenem or imipenem. RESULTS: Sensitivity, specificity, negative predictive value, and positive predictive value were of 80.8% (CI95 76.3%-84.6%), 66.2% (58.1%-73.5%), 59.3% (51.5%-66.6%), and 85.0% (80.7% - 88.5%) for the old CA-SFM algorithm and 97.8% (95.5%-99.0%), 45.5% (37.5%-53.7%), 89.7% (80.3%-95.2%), and 80.9% (76.9%-84.4%) for the novel CA-SFM algorithm. DISCUSSION: The novel CA-SFM algorithm possesses the best performance for the screening of CPE particularly in countries with a high prevalence of OXA-48-like producers.

Use of a chromogenic medium with and without selective enrichment to screen for carbapenemase-producing Enterobacterales (CPE) from canine and feline fecal specimens during an outbreak of NDM-5-producing Escherichia coli.

Carbapenemase-producing Enterobacterales (CPE) are one of the most urgent threats to human healthcare globally. Descriptions of CPE outbreaks in veterinary hospitals suggest the need for screening strategies for CPE from companion animals. Our aim was to optimize a chromogenic agar method with and without selective enrichment to isolate CPE from companion animal feces in an ongoing outbreak of New Delhi metallo-ß-lactamse-5 Escherichia coli. A limit of detection (LOD) assay for spiked canine and feline feces was performed for both methods using a carbapenamase-producing E. coli (24213-18); the LOD (1.5 × 103 cfu/g of feces) was equivalent to that reported for human fecal specimens. We screened 1,247 companion animal fecal specimens for carriage of CPE by 1) direct plating to chromogenic agar and 2) plating to chromogenic agar following selective enrichment. Twenty-one specimens were positive for CPE by both direct culture and enrichment culture. No specimens were positive with selective enrichment and negative by direct culture. A selective enrichment step did not result in any increased recovery of CPE from companion animals, which suggests that enrichment broth may not be necessary for outbreak surveillance testing. It is important to continue to validate methods for the detection of CPE in companion animals as outbreaks become more common in veterinary facilities.

Model-based evaluation of admission screening strategies for the detection and control of carbapenemase-producing Enterobacterales in the English hospital setting.

BACKGROUND: Globally, detections of carbapenemase-producing Enterobacterales (CPE) colonisations and infections are increasing. The spread of these highly resistant bacteria poses a serious threat to public health. However, understanding of CPE transmission and evidence on effectiveness of control measures is severely lacking. This paper provides evidence to inform effective admission screening protocols, which could be important in controlling nosocomial CPE transmission. METHODS: CPE transmission within an English hospital setting was simulated with a data-driven individual-based mathematical model. This model was used to evaluate the ability of the 2016 England CPE screening recommendations, and of potential alternative protocols, to identify patients with CPE-colonisation on admission (including those colonised during previous stays or from elsewhere). The model included nosocomial transmission from colonised and infected patients, as well as environmental contamination. Model parameters were estimated using primary data where possible, including estimation of transmission using detailed epidemiological data within a Bayesian framework. Separate models were parameterised to represent hospitals in English areas with low and high CPE risk (based on prevalence). RESULTS: The proportion of truly colonised admissions which met the 2016 screening criteria was 43% in low-prevalence and 54% in high-prevalence areas respectively. Selection of CPE carriers for screening was improved in low-prevalence areas by adding readmission as a screening criterion, which doubled how many colonised admissions were selected. A minority of CPE carriers were confirmed as CPE positive during their hospital stay (10 and 14% in low- and high-prevalence areas); switching to a faster screening test pathway with a single-swab test (rather than three swab regimen) increased the overall positive predictive value with negligible reduction in negative predictive value. CONCLUSIONS: Using a novel within-hospital CPE transmission model, this study assesses CPE admission screening protocols, across the range of CPE prevalence observed in England. It identifies protocol changes-adding readmissions to screening criteria and a single-swab test pathway-which could detect similar numbers of CPE carriers (or twice as many in low CPE prevalence areas), but faster, and hence with lower demand on pre-emptive infection-control resources. Study findings can inform interventions to control this emerging threat, although further work is required to understand within-hospital transmission sources.

Case Report: Disseminated Edwardsiella tarda infection in an immunocompromised patient.

Human infection caused by bacteria of the Edwardsiella genus is rare and most often presents with gastroenteritis that rarely requires antibiotics. Our case report describes a medically complex patient with chronic steroid use contributing to an immunocompromised state, who presented with fever and abdominal pain. The patient was later found to have Edwardsiella tarda (E. tarda) bacteremia and underwent paracentesis confirming E. tarda bacterial peritonitis requiring a prolonged antibiotic course. This case report aims to illustrate the presentation, diagnosis, and management of an uncommon infection that can have severe complications especially among immunocompromised patients.

Prevalence of carbapenemase producing Enterobacterales colonization and risk factor of clinical infection.

BACKGROUND: Carbapenemase-producing Enterobacterales (CPE) are global concerns in infection control, and the number of CPE outbreaks in hospitals is increasing despite the strengthening of contact precautions. This study aimed to confirm the prevalence and transition rate of CPE infection from stool surveillance culture and to identify the acquisition pathway of CPE. METHODS: This is a longitudinal review of patients with stool surveillance cultures at a tertiary center in Seoul, South Korea, from July 2018 to June 2020. Pulsed-field gel electrophoresis, multi-locus sequence typing, and whole genome sequencing were performed for carbapenemase-producing Klebsiella pneumoniae and Escherichia coli strains. RESULTS: Among 1620 patients who had undergone stool CPE surveillance cultures, only 7.1% of active surveillance at the Emergency Room (ER) and 4.4% of universal surveillance in the Intensive Care Unit (ICU) were stool CPE positive. The transition rates from stool carriers to clinical CPE infections were 29.4% in the ER and 31.3% in the ICU. However, it was significantly high (55.0%) in the initial stool CPE-negative ICU patients. Among the initial stool CPE-positive patients, hypertension (61% vs. 92.3%, P = 0.004), malignancy (28.8% vs. 53.8%, P = 0.027), and mechanical ventilation (25.4% vs. 53.8%, P = 0.011) were significant risk factors for clinical CPE infection. Molecular typing revealed that sequence type (ST) 307 and ST 395 were dominant in K. pneumoniae, and ST 410 was dominant in E. coli isolates. CONCLUSIONS: Active surveillance showed a higher detection rate than universal stool CPE screening, and one-third of positive stool CPE specimens ultimately developed subsquent clinical CPE infection. According to the molecular typing of the identified CPE strains, in-hospital spread prevailed over external inflow, and the transition rate to clinical CPE was particularly high in the ICU. Therefore, in order to control CPE propagation, not only active surveillance to block inflow from outside, but also continuous ICU monitoring within the hospital is necessary.

Who should be screened for carbapenemase-producing Enterobacterales and when? A systematic review.

Carbapenemase-producing Enterobacterales (CPE) cases increases every year in Denmark and the proportion of CPE-positive cases with a travel history decreases. Several epidemiological links show transmission in Danish healthcare setting indicating infection prevention and control challenges and raising questions about the Danish CPE screening protocol. The aim of this review was to identify additional risk factors to those described in the Danish CPE-screening protocol in order to detect the Danish CPE-positive patients and thereby reduce the risk of transmission and outbreaks. A systematic literature search was conducted in PubMed, Embase and Cochrane Library during March 2022. A total of 1487 articles were screened, and 19 studies were included. Retrieved studies dealt with patients with laboratory-confirmed CPE (colonization and/or infection) and associated risk factors. Antimicrobial therapy, especially broad-spectrum antimicrobial agents, prior or current hospitalization of approximately one week in ICU and 20-28 days in other wards and travel history with or without hospitalization abroad were significant risk factors associated with CPE acquisition. Comorbidities and invasive procedures were identified as risk factors, but without identifying specific comorbidities or invasive procedures associated with risk for CPE-acquisition. This study suggests the need to develop an additional algorithm for CPE-screening in Denmark. In addition to risk-based screening on admission, screening of inpatients should be considered. The screening protocol might include screening of inpatients with comorbidities who are hospitalized >1 week in ICU or >3 weeks in other wards and who have previously received or currently are receiving antibiotic treatment. Further research is needed to develop a new CPE-screening algorithm.

The impact of enhanced screening for carbapenemase-producing Enterobacterales in an acute care hospital in South Korea.

BACKGROUND: Carbapenemase-producing Enterobacterales (CPE) poses a significant challenge to infection control in healthcare settings. Active screening is recommended to prevent intra-hospital CPE transmission. METHODS: CPE screening was initiated at a 660-bed hospital in South Korea in September 2018, targeting patients previously colonized/infected or admitted to outside healthcare facilities (HCFs) within 1 month. Universal intensive care unit (ICU) screening was performed at the time of admission. After a hospital-wide CPE outbreak in July-September 2019, the screening program was enhanced by extending the indications (admission to any HCF within 6 months, receipt of hemodialysis) with weekly screening of ICU patients. The initial screening method was changed from screening cultures to the Xpert Carba-R assay. The impact was assessed by comparing the CPE incidence per 1000 admissions before (phase 1, September 2018-August 2019) and after instituting the enhanced screening program (phase 2, September 2019-December 2020). RESULTS: A total of 13,962 (2,149 and 11,813 in each phase) were screened as indicated, among 49,490 inpatients, and monthly screening compliance increased from 18.3 to 93.5%. Compared to phase 1, the incidence of screening positive patients increased from 1.2 to 2.3 per 1,000 admissions (P = 0.005) during phase 2. The incidence of newly detected CPE patients was similar (3.1 vs. 3.4, P = 0.613) between two phases, but the incidence of hospital-onset CPE patients decreased (1.9 vs. 1.1, P = 0.018). A significant decrease was observed (0.5 to 0.1, P = 0.014) in the incidence of patients who first confirmed CPE positive through clinical cultures without a preceding positive screening. Compared to phase 1, the median exposure duration and number of CPE contacts were also markedly reduced in phase 2: 10.8 days vs. 1 day (P < 0.001) and 11 contacts vs. 1 contact (P < 0.001), respectively. During phase 2, 42 additional patients were identified by extending the admission screening indications (n = 30) and weekly in-ICU screening (n = 12). CONCLUSIONS: The enhanced screening program enabled us to identify previously unrecognized CPE patients in a rapid manner and curtailed a hospital-wide CPE outbreak. As CPE prevalence increases, risk factors for CPE colonization can broaden, and hospital prevention strategies should be tailored to the changing local CPE epidemiology.

Transmission of Carbapenem-Resistant Enterobacterales in an Overcrowded Emergency Department: Controlling the Spread to the Hospital.

BACKGROUND: Overcrowded emergency departments (EDs) may increase the risk of carbapenem-resistant Enterobacterales (CRE) transmission. METHODS: We conducted a quasi-experimental study divided into 2 phases (baseline and intervention) to investigate the impact of an intervention on the acquisition rate and identify risk factors for CRE colonization in an ED of a tertiary academic hospital in Brazil. In both phases, we did universal screening with rapid molecular test (blaKPC, blaNDM, blaOXA48, blaOXA23, and blaIMP) and culture. At baseline, both screening test results were not reported, and patients were put under contact precautions (CP) based on previous colonization or infection by multidrug-resistant organisms. During the intervention, all patients hospitalized in the ED were placed in empiric CP and the result of CRE screening was reported; if negative, patients were released from CP. Patients were rescreened if they stayed >7 days in the ED or were transferred to an intensive care unit. RESULTS: A total of 845 patients were included: 342 in baseline and 503 in intervention. Colonization at admission was 3.4% by culture and molecular test. Acquisition rates during ED stay dropped from 4.6% (11/241) to 1% (5/416) during intervention (P = .06). The aggregated antimicrobial use in the ED decreased from phase 1 to phase 2 (804 defined daily doses [DDD]/1000 patients to 394 DDD/1000 patients, respectively). Length of stay >2 days in the ED was a risk factor for CRE acquisition (adjusted odds ratio, 4.58 [95% confidence interval, 1.44-14.58]; P = .01). CONCLUSIONS: Early empiric CP and rapid identification of CRE-colonized patients reduce cross-transmission in ED. Nevertheless, staying >2 days in ED compromised efforts.

Edwardsiella tarda is an Important Causative Agent of Maternal-Fetal Infections in Pregnant Women: a Case Report and Japanese Literature Review.

Volume 76, no 1, p. 80-83, 2023. Page 81, Table 1 should appear as shown below.

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 â€‹< â€‹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.

Clinical impact of time to results from the microbiology laboratory in bloodstream infections caused by carbapenemase-producing Enterobacterales (TIME-CPE STUDY).

OBJECTIVES: To evaluate the impact of time to results (TTR) on the outcome of patients with carbapenemase-producing Enterobacterales bloodstream infections (CPE-BSI). METHODS: Times-series study conducted from January 2014 to December 2021, selecting patients with first CPE-BSI episodes. Periods of intervention were defined according to implementation of diagnostic bundle tests in the microbiology laboratory: pre-intervention (January 2014-December 2017) and post-intervention (January 2018-December 2021). TTR was defined as time elapsed from positivity time of the blood culture bottles to physicians' notification of CPE-BSI episodes, and was evaluated in patients who received inappropriate empirical and switched to appropriate targeted treatment (switch group). Analysis of a composite unfavourable outcome (mortality at Day 30 and/or persistent and/or recurrent bacteraemia) was performed for the total episodes and in the switch group. RESULTS: One hundred and nine episodes were analysed: 66 pre-intervention and 43 post-intervention. Compared with pre-intervention, patients in the post-intervention period were younger (68 versus 63 years, P = 0.04), had INCREMENT score > 7 (31.8% versus 53.5%, P = 0.02) and unfavourable outcome (37.9% versus 20.9%, P = 0.04). Proportion of TTR > 30 h was more frequent pre-intervention than post-intervention (61.7% versus 35.5%, P = 0.02). In multivariate analysis of the 109 episodes, source other than urinary or biliary (OR 2.76, 95% CI 1.11-6.86) was associated with unfavourable outcome, while targeted appropriate treatment trended to being protective (OR 0.17, 95% CI 0.03-1.00). Considering the switch group (n = 78), source other than urinary or biliary (OR 14.9, 95% CI 3.25-69.05) and TTR > 30 h (OR 4.72, 95% CI 1.29-17.22) were associated with unfavourable outcome. CONCLUSIONS: Decreased TTR in the post-intervention period was associated with the outcome in patients with CPE-BSI episodes.

Cronobacter sakazakii Infections in Two Infants Linked to Powdered Infant Formula and Breast Pump Equipment - United States, 2021 and 2022.

Cronobacter sakazakii, a species of gram-negative bacteria belonging to the Enterobacteriaceae family, is known to cause severe and often fatal meningitis and sepsis in young infants. C. sakazakii is ubiquitous in the environment, and most reported infant cases have been attributed to contaminated powdered infant formula (powdered formula) or breast milk that was expressed using contaminated breast pump equipment (1-3). Previous investigations of cases and outbreaks have identified C. sakazakii in opened powdered formula, breast pump parts, environmental surfaces in the home, and, rarely, in unopened powdered formula and formula manufacturing facilities (2,4-6). This report describes two infants with C. sakazakii meningitis reported to CDC in September 2021 and February 2022. CDC used whole genome sequencing (WGS) analysis to link one case to contaminated opened powdered formula from the patient's home and the other to contaminated breast pump equipment. These cases highlight the importance of expanding awareness about C. sakazakii infections in infants, safe preparation and storage of powdered formula, proper cleaning and sanitizing of breast pump equipment, and using WGS as a tool for C. sakazakii investigations.

Quantification of time delay between screening and subsequent initiation of contact isolation for carriers of extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales: A post hoc subgroup analysis of the R-GNOSIS WP5 Trial.

OBJECTIVES: The aim of this study was to quantify the time delay between screening and initiation of contact isolation for carriers of extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales (ESBL-E). METHODS: This study was a secondary analysis of contact isolation periods in a cluster-randomized controlled trial that compared 2 strategies to control ESBL-E (trial no. ISRCTN57648070). Patients admitted to 20 non-ICU wards in Germany, the Netherlands, Spain, and Switzerland were screened for ESBL-E carriage on admission, weekly thereafter, and on discharge. Data collection included the day of sampling, the day the wards were notified of the result, and subsequent ESBL-E isolation days. RESULTS: Between January 2014 and August 2016, 19,122 patients, with a length of stay ≥2 days were included. At least 1 culture was collected for 16,091 patients (84%), with a median duration between the admission day and the day of first sample collection of 2 days (interquartile range [IQR], 1-3). Moreover, 854 (41%) of all 2,078 ESBL-E carriers remained without isolation during their hospital stay. In total, 6,040 ESBL-E days (32% of all ESBL-E days) accrued for patients who were not isolated. Of 2,078 ESBL-E-carriers, 1,478 ESBL-E carriers (71%) had no previous history of ESBL-E carriage. Also, 697 (34%) were placed in contact isolation with a delay of 4 days (IQR, 2-5), accounting for 2,723 nonisolation days (15% of ESBL-E days). CONCLUSIONS: Even with extensive surveillance screening, almost one-third of all ESBL-E days were nonisolation days. Limitations in routine culture-based ESBL-E detection impeded timely and exhaustive implementation of targeted contact isolation.