Cephalosporin-resistant Enterobacteriaceae Research Articles

Sensitivity and specificity of Nanopore sequencing for detecting carbapenem and 3rd-generation cephalosporin-resistant Enterobacteriaceae in urine samples: Real-time simulation with public antimicrobial resistance gene database

ObjectivesTo evaluate the accuracy of beta-lactamase gene detection directly from urine samples by Nanopore sequencing. MethodsDNA was extracted from bacterial pellets in spun urine. The purified DNA was then sequenced in native form by a Nanopore sequencer (MinION) to identify the organisms and beta-lactamase genes. Results were compared to routine urine cultures and standard antimicrobial susceptibility tests (AST). ResultsWe processed 60 urine samples of which routine cultures grew Enterobacteriaceae, including 28 carbapenem-resistant (CRE), 17 extended-spectrum beta-lactamase (ESBL) or AmpC producing, and 15 non-ESBL/AmpC phenotypes. We excluded 7 samples with extremely low DNA amounts (<1 ng/μl) for a final case of 53 in total. The sensitivity of antimicrobial resistance gene detection within 6 h, the optimal duration from real-time simulation, of Nanopore sequencing for the diagnosis of carbapenem-resistant and ceftriaxone-resistant phenotypes was 73.9 % (95%CI 56.0–91.9 %) and 81.1 % (95%CI 68.5–93.7 %), while the specificity was 96.7 % (95%CI 90.2–100.0 %) and 56.3 % (95%CI 31.9–80.6 %), respectively. The median times for MinION to generate DNA reads containing carbapenemase and ESBL/AmpC genes were 93 min (IQR 17–245.5) and 99 min (IQR 31.25–269.75) after sequencing commencement, respectively. ConclusionsNanopore sequencing can identify bacterial genotypic resistance in urine and may enable clinicians to adjust antimicrobial therapy earlier than routine AST.

Development of novel antimicrobials with engineered endolysin LysECD7-SMAP to combat Gram-negative bacterial infections

BackgroundAmong the non-traditional antibacterial agents in development, only a few targets critical Gram-negative bacteria such as carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii or cephalosporin-resistant Enterobacteriaceae. Endolysins and their genetically modified versions meet the World Health Organization criteria for innovation, have a novel mode of antibacterial action, no known bacterial cross-resistance, and are being intensively studied for application against Gram-negative pathogens.MethodsThe study presents a multidisciplinary approach, including genetic engineering of LysECD7-SMAP and production of recombinant endolysin, its analysis by crystal structure solution following molecular dynamics simulations and evaluation of antibacterial properties. Two types of antimicrobial dosage forms were formulated, resulting in lyophilized powder for injection and hydroxyethylcellulose gel for topical administration. Their efficacy was estimated in the treatment of sepsis, and pneumonia models in BALB/c mice, diabetes-associated wound infection in the leptin receptor-deficient db/db mice and infected burn wounds in rats.ResultsIn this work, we investigate the application strategies of the engineered endolysin LysECD7-SMAP and its dosage forms evaluated in preclinical studies. The catalytic domain of the enzyme shares the conserved structure of endopeptidases containing a putative antimicrobial peptide at the C-terminus of polypeptide chain. The activity of endolysins has been demonstrated against a range of pathogens, such as Klebsiella pneumoniae, A. baumannii, P. aeruginosa, Staphylococcus haemolyticus, Achromobacter spp, Burkholderia cepacia complex and Haemophylus influenzae, including those with multidrug resistance. The efficacy of candidate dosage forms has been confirmed in in vivo studies. Some aspects of the interaction of LysECD7-SMAP with cell wall molecular targets are also discussed.ConclusionsOur studies demonstrate the potential of LysECD7-SMAP therapeutics for the systemic or topical treatment of infectious diseases caused by susceptible Gram-negative bacterial species and are critical to proceed LysECD7-SMAP-based antimicrobials trials to advanced stages.

From Swiffers to Solutions: The Impact of Environmental Sampling in the Veterinary Medical Center at OSU

Background: In 2018, the Ohio State University College of Veterinary Medicine (OSU CVM) implemented an Antimicrobial Stewardship Program, central to which was the integration of an environmental surveillance (ES) program. The ES focuses on pathogens recognized as urgent threats to public health by the Centers for Disease Control and Prevention. The pathogens currently targeted include carbapenemase-producing Enterobacterales (CPE), Salmonella spp., methicillin-resistant Staphylococcus spp. (MRSs), vancomycin resistant Enterococcus spp., and enrofloxacin resistant Pseudomonas aeruginosa. Identification of these pathogens allows the hospital to be aware of the local environmental microflora which can act as a sentinel for disease in the hospital, potentially causing healthcare associated infections. Therefore, the objective of this program is to identify resistant bacterial pathogens, characterize their resistance profiles, analyze prevalence patterns, and initiate infection control interventions where needed in the OSU VMC. Method: From January 2018 through December 2023, a total of 5449 samples were collected from approximately 86 locations across the OSU VMC encompassing the small animal, equine, and farm animal sections. A majority (64%, n=3561) of samples were collected from the small animal hospital, with the farm animal section contributing 1055 samples and the equine section 899. Areas sampled were frequented by both humans and animals, as well as surfaces exclusively touched by humans. Samples were collected using Swiffers® and processed through selective culture media. Result: Approximately half (52%, n=2890) of the samples collected represented human-touch only surfaces. A total of 3794 bacterial isolates were recovered, with an overall low prevalence for all targeted pathogens. Prevalence of CPE was 2% (n=103), with Enterobacter species being the most common. Recovery of MRSs was 8.5% (n=464) and Salmonella species was 1% (n=47). Conclusion: Through this initiative, the equine division of the OSU VMC collaborated with the antimicrobial stewardship team to enhance their Salmonella fecal and ES practices. In 2019, ES was critical in identifying persistent CPE and extended-spectrum cephalosporin-resistant Enterobacteriaceae in the ICU and surrounding areas of the small animal hospital. Effective measures were taken to halt the spread of ESC among patients and eliminate CPE in the environment. With the discovery of a new CPE in early 2023 in the small animal ICU and nearby areas, the program initiated targeted ES and cleaning and disinfection protocols, to identify contaminated areas and control disease transmission. These efforts have increased patient safety, health, and well-being, demonstrating how ES can be an important tool for infection control and prevention in veterinary settings.

Antibiotic Prescriptions in Critically Ill Patients with Bloodstream Infection Due to ESBL-Producing Enterobacteriaceae: Compliance with the French Guidelines for the Treatment of Infections with Third-Generation Cephalosporin-Resistant Enterobacteriaceae-A Multicentric Retrospective Cohort Study.

National and international guidelines were recently published regarding the treatment of Enterobacteriaceae resistant to third-generation cephalosporins infections. We aimed to assess the implementation of the French guidelines in critically ill patients suffering from extended-spectrum β-lactamase-producing Enterobacteriaceae bloodstream infection (ESBL-E BSI). We conducted a retrospective observational cohort study in the ICU of three French hospitals. Patients treated between 2018 and 2022 for ESBL-E BSI were included. The primary assessment criterion was the proportion of adequate empirical carbapenem prescriptions, defined as prescriptions consistent with the French guidelines. Among the 185 included patients, 175 received an empirical anti-biotherapy within 24 h of ESBL-E BSI onset, with a carbapenem for 100 of them. The proportion of carbapenem prescriptions consistent with the guidelines was 81%. Inconsistent prescriptions were due to a lack of prescriptions of a carbapenem, while it was recommended in 25% of cases. The only factor independently associated with adequate empirical carbapenem prescription was ESBL-E colonization (OR: 107.921 [9.303-1251.910], p = 0.0002). The initial empirical anti-biotherapy was found to be appropriate in 83/98 patients (85%) receiving anti-biotherapy in line with the guidelines and in 56/77 (73%) patients receiving inadequate anti-biotherapy (p = 0.06). Our results illustrate the willingness of intensivists to spare carbapenems. Promoting implementation of the guidelines could improve the proportion of initial appropriate anti-biotherapy in critically ill patients with ESBL-E BSI.

Colonizations and infections due to 3GCR Enterobacteriaceae in a University hospital in Italy

Abstract Background The spread of third-generation cephalosporin-resistant Enterobacteriaceae (3GCREB) is an increasing issue in terms of antimicrobial resistance and infection prevention and control (IPC), especially in the hospital setting. We aimed to investigate the burden of colonizations and infections caused by 3GCREB in an Italian teaching hospital. Methods We performed a retrospective study on cases of 3GCREB isolation from microbiological specimens (from gastrointestinal, urinary, blood, respiratory and cutaneous systems) which were detected over a year period (January-December 2022) at the University Hospital of Verona, Italy. We reviewed the corresponding patients’ charts to retrieve clinical information and classify cases as colonizations vs. infections. Infections counted as hospital-acquired (HAI) when the 3GCREB was detected after the third day following admission, otherwise as community-acquired infection (CAI). Results Of 2,451 3GCREB isolates retrieved, 1,815 (74.1%) were from rectal swabs. The monthly detection trend was consistent throughout the year with a minimum in February (n = 159) and a maximum in August (n = 238); monthly average was 204 isolates. The majority of 3GCREB isolates (n = 1,887; 77%) were classified as colonizations. Of the 564 3GCREB isolates which were classified as infections (23% of total isolates), 305 (54.1%) were HAIs and 259 (45.9%) were CAIs. The highest proportion of HAIs (n = 121; 39.7%) was detected in medical units, followed by intensive care areas (n = 100; 32.8%) and surgical units (n = 84; 27.5%). Conclusions Comparing the percentages of patients with 3GCREB colonization and infection, we conclude the presence of 3GCREB in our hospital to be about 3 times higher than when only patients with 3GCREB infections are considered. This highlights the importance of surveillance to protect fragile patients. IPC training of staff is essential to counter the intra-hospital spread of these pathogens. Key messages • Prevalence of 3GCREB is an increasing healthcare issue in the hospital setting and medical directions should focus on staff IPC training to counter the spread of these pathogens. • Detection of 3GCREB colonizations is crucial to track the spread of multidrug-resistant organisms, identify cases and protect fragile patients.

Transfer of Extended Spectrum Cephalosporin Resistant Enterobacteriaceae Among Patients on an HSCT Unit and the Value of Surveillance and Contact Isolation

The mechanism(s) of acquisition of extended-spectrum cephalosporin-resistant Enterobacteriaceae (ESCRE) on inpatient hospital units dedicated to hematopoietic stem cell transplantation (HSCT) is unclear. The objectives of this study were to determine whether ESCRE organisms are transmitted among patients housed on a HSCT unit, clarify the mechanisms involved, and determine whether routine surveillance for ESCRE carriage and contact isolation for ESCRE carriers is beneficial. The study was conducted on a 30-bed inpatient unit dedicated to the care of patients with hematologic malignancies and HSCT recipients. To investigate whether ESCRE organisms may be transmitted vertically to subsequent room occupants, presumably through contamination of room surfaces, we (1) cultured 6 high touch areas in 10 rooms before and 9 rooms after terminal cleaning that had been occupied by patients with ESCRE carriage, (2) determined the in vitro survivals of our most common clinical ESCRE species, and (3) followed the subsequent room occupants of 54 consecutive ESCRE colonized patients for the development of inpatient acquired ESCRE carriage. To investigate whether ESCRE organisms are transmitted horizontally among inpatients we (1) sequenced 60 available ESCRE Escherichia coli isolates obtained from unit inpatients and searched for identities using complete-genome multisequence locus typing (cgMLST) and (2) retrospectively tabulated the cumulative rates of acquired ESCRE carriage in 356 patients admitted for a first HSCT before (200 patients) or after (156 patients) institution of universal ESCRE stool surveillance and contact isolation for carriers. No ESCRE organisms were cultured from patient rooms before or after terminal cleaning. In vitro, few, if any, ESCRE organisms survived longer than 2 hours. Nine of the subsequent occupants of a room in which a patient with ESCRE carriage had resided were detected with ESCRE carriage, only 2 of whom carried the same species as that of the prior occupant. DNA sequencing and cgMLST determination of the 60 E. coli isolates showed 53 cgMLST strains. Seven of the 53 strains were shared by 2 patients. After institution of universal ESCRE surveillance/isolation there was a significant decline in acquired ESCRE carriage among HSCT recipients. We conclude that vertical transmission of ESCRE organisms through room contamination appears to be uncommon on modern HSCT units. Conversely, our results are consistent with the horizontal spread of ESCRE organisms, probably mediated by intermediate vectors such as personnel or shared equipment. Further studies are needed to better define the magnitude of and risk factors for ESCRE horizontal transfers and the benefits of ESCRE surveillance/isolation.

Mechanism of action of cefiderocol.

Gram-negative bacilli are intrinsically resistant to many antibiotics due to the low permeability of their outer membrane. The most effective strategy to solve this problem has been the design of antibiotics that cross the membrane using specific transport systems. This is the case of cefiderocol, which, unlike cefepime or ceftazidime, has a chlorocatechol group at the end of the C-3 side chain. This group is recognized by transporters located in the outer membrane that allow cefiderocol to accumulate in the periplasmic space. Furthermore, cefiderocol is not a substrate for efflux pumps and the configuration of the side chains at C-7 and in particular at C-3 confer it a high stability against hydrolysis by most beta-lactamases of clinical interest including class A (KPC, BLEEs), C (ampC) or D (OXA-48) serine beta-lactamases and metallo-betalactamases (NDM, VIM. IMP). In order to better understand the mechanism of action of cefiderocol, the importance of iron in bacterial metabolism and the competition for iron between bacteria and host are reviewed.The indiscriminate and massive antibiotic use in the clinical practice and in agriculture or cattle during the past few decades has produced a serious world health problem that entails high morbidity and mortality: the antibiotic multi-drug resistance. In 2017 and 2019, the World Health Organization published a list of urgent threats and priorities in the context of drug resistance, which only included Gram-negative bacteria and specially focused on carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa, as well as carbapenem and third generation cephalosporin-resistant Enterobacteriaceae. This scenario emphasizes the need of developing and testing new antibiotics from different families, such as new beta-lactams, highlighting cefiderocol and its original mechanism of action; new beta-lactamase inhibitors, with vaborbactam or relebactam among others; new quinolones such as delafloxacin, and also omadacycline or eravacycline, as members of the tetracycline family. The present work reviews the importance and impact of Gram-negative bacterial infections and their resistance mechanisms, and analyzes the current therapeutic paradigm as well as the role of new antibiotics with a promising future in the era of multi and pan-drug resistance.

Resistance to beta-lactams in Gram-negative bacilli: relevance and potential therapeutic alternatives.

The indiscriminate and massive antibiotic use in the clinical practice and in agriculture or cattle during the past few decades has produced a serious world health problem that entails high morbidity and mortality: the antibiotic multi-drug resistance. In 2017 and 2019, the World Health Organization published a list of urgent threats and priorities in the context of drug resistance, which only included Gram-negative bacteria and specially focused on carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa, as well as carbapenem and third generation cephalosporin-resistant Enterobacteriaceae. This scenario emphasizes the need of developing and testing new antibiotics from different families, such as new beta-lactams, highlighting cefiderocol and its original mechanism of action; new beta-lactamase inhibitors, with vaborbactam or relebactam among others; new quinolones such as delafloxacin, and also omadacycline or eravacycline, as members of the tetracycline family. The present work reviews the importance and impact of Gram-negative bacterial infections and their resistance mechanisms, and analyzes the current therapeutic paradigm as well as the role of new antibiotics with a promising future in the era of multi and pan-drug resistance.

Extended spectrum cephalosporin resistant enterobacteriaceae carriage and infection in patients admitted with newly-diagnosed acute leukemia

Current information is limited on the incidence, risk factors, and consequences of extended-spectrum cephalosporin resistant Enterobacteriaceae (ESCRE) carriage in patients undergoing therapy for newly-diagnosed acute leukemia. We monitored 300 consecutive patients who submitted a first stool within the first week of initial hospitalization for initial and hospital acquired ESCRE carriage. Selected available isolates underwent DNA sequencing for determination of strain typing and resistance genes. 19 (6%) patients had ESCRE in their initial stool, and there was continued risk for new acquisition throughout their multiple hospitalizations. Patients with AML had more acquired carriage during their initial hospitalization. Increased hospitalizations and male sex were risk factors for detected acquired ESCRE carriage. ESCRE stool carriage was predictive for ESCRE BSI but not for overall survival. Sequencing revealed that E. coli ESCRE isolates contained primarily ESBL, while Enterobacter spp. and Citrobacter spp. showed primarily AmpC genes. The antibiotic sensitivity patterns for ESCRE BSI isolates reflected these genome findings. ESCRE carriage is common in patients with acute leukemia undergoing repeated hospitalizations and increases the risk for ESCRE BSI. ESCRE genera express differing resistance genes which may be predictive for empiric antibiotic efficacy.

A prospective multicentre screening study on multidrug-resistant organisms in intensive care units in the Dutch-German cross-border region, 2017 to 2018: the importance of healthcare structures.

BackgroundAntimicrobial resistance poses a risk for healthcare, both in the community and hospitals. The spread of multidrug-resistant organisms (MDROs) occurs mostly on a local and regional level, following movement of patients, but also occurs across national borders.AimThe aim of this observational study was to determine the prevalence of MDROs in a European cross-border region to understand differences and improve infection prevention based on real-time routine data and workflows.MethodsBetween September 2017 and June 2018, 23 hospitals in the Dutch (NL)–German (DE) cross-border region (BR) participated in the study. During 8 consecutive weeks, patients were screened upon admission to intensive care units (ICUs) for nasal carriage of meticillin-resistant Staphylococcus aureus (MRSA) and rectal carriage of vancomycin-resistant Enterococcus faecium/E. faecalis (VRE), third-generation cephalosporin-resistant Enterobacteriaceae (3GCRE) and carbapenem-resistant Enterobacteriaceae (CRE). All samples were processed in the associated laboratories.ResultsA total of 3,365 patients were screened (median age: 68 years (IQR: 57–77); male/female ratio: 59.7/40.3; NL-BR: n = 1,202; DE-BR: n = 2,163). Median screening compliance was 60.4% (NL-BR: 56.9%; DE-BR: 62.9%). MDRO prevalence was higher in DE-BR than in NL-BR, namely 1.7% vs 0.6% for MRSA (p = 0.006), 2.7% vs 0.1% for VRE (p < 0.001) and 6.6% vs 3.6% for 3GCRE (p < 0.001), whereas CRE prevalence was comparable (0.2% in DE-BR vs 0.0% in NL-BR ICUs).ConclusionsThis first prospective multicentre screening study in a European cross-border region shows high heterogenicity in MDRO carriage prevalence in NL-BR and DE-BR ICUs. This indicates that the prevalence is probably influenced by the different healthcare structures.

Isolation of third generation cephalosporin resistant Enterobacteriaceae from retail meats and detection of extended spectrum beta-lactamase activity

Various methods have been described to isolate third generation cephalosporin (3GC) resistant Enterobacteriaceae from foods, but it is not known how comparable they are between studies. Here, the performance of five enrichment broths and two selective agars are compared for their ability to isolate 3GC resistant Enterobacteriaceae from retail chicken, beef, pork, and veal samples. The results showed equivalence between Enterobacteriaceae enrichment broth (EE), lauryl sulfate broth (LST), and modified typtone soy broth (mTSB). Lower isolation rates were observed when LST and mTSB were supplemented with the 3GC antibiotic cefotaxime. The overall performance of MacConkey agar supplemented with cefotaxime and a proprietary selective agar (ESBL CHROMagar) was equivalent, although differences linked to the microbiota of specific meat commodities were noted. Regardless of the isolation method, further screening was required to confirm the taxonomy and resistance of the presumptive positive strains. Approximately 40% of confirmed 3GC resistant foodborne Enterobacteriaceae strains tested positive for extended spectrum beta-lactamase (ESBL) activity. Strains that were resistant to ceftriaxone and susceptible to cefoxitin were more likely to test positive for ESBL activity, as were strains that possessed either of two ESBL genes (blaSHV or blaTEM). Based on our results, we recommend using an antibiotic-free enrichment broth, two selective agars, and an isolate screening strategy to isolate 3GC resistant Enterobacteriaceae from retail meats. Antibiotic susceptibility testing and/or PCR screening for blaSHV or blaTEM can then be used to identify ESBL producing strains among the 3GC resistant meat isolates. The adoption of this approach by the research community will enable more effective monitoring of antibiotic resistance rates and trends among foodborne Enterobacteriaceae over time and across jurisdictions.

Prevalence and characterization of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from raw vegetables retailed in Southern Thailand.

BackgroundThe increasing prevalence of broad-spectrum ampicillin-resistant and third-generation cephalosporin-resistant Enterobacteriaceae, particularly Escherichia coli and Klebsiella pneumoniae, has become a global concern, with its clinical impacts on both human and veterinary medicine. This study examined the prevalence, antimicrobial susceptibility, and molecular genetic features of extended-spectrum β-lactamase (ESBL)-producing E. coli and K. pneumoniae isolates from 10 types of raw vegetables.MethodsIn total, 305 samples were collected from 9 markets in Nakhon Si Thammarat, Thailand, in 2020.ResultsESBL-producing E. coli and K. pneumoniae isolates were found in 14 of the 305 samples obtained from 7 out of 10 types of vegetables (4.6% of the total). Further, 14 ESBL-producing E. coli (n = 5/14) and K. pneumoniae isolates (n = 9/14) (1.6% and 3.0%, respectively) were highly sensitive to β-lactam/carbapenem antibiotics (imipenem, 100%). ESBL-producing E. coli (n = 4) and K. pneumoniae isolates (n = 8) were also sensitive to non-β-lactam aminoglycosides (amikacin, 80.00% and 88.89%, respectively). ESBL producers were most resistant to β-lactam antibiotics, including ampicillin (85.71%) and the cephalosporins cefotaxime and ceftazidime (64.29%). The most frequently detected gene in ESBL-producing E. coli and K. pneumoniae was blaSHV. However, two ESBL-producing E. coli isolates also carried three other ESBL-encoding variants, blaTEM, blaCTX-M1, blaGES and blaTEM, blaSHV, blaCTX-M9, which may be due to their association with food chains and humans.DiscussionIndeed, our results suggest that raw vegetables are an important source of ESBL-resistant E. coli and K. pneumoniae, which are potentially transmittable to humans via raw vegetable intake.

Multi-country cross-sectional study of colonization with multidrug-resistant organisms: protocol and methods\xa0for the Antibiotic Resistance in Communities and Hospitals (ARCH) studies

BackgroundAntimicrobial resistance is a global health emergency. Persons colonized with multidrug-resistant organisms (MDROs) are at risk for developing subsequent multidrug-resistant infections, as colonization represents an important precursor to invasive infection. Despite reports documenting the worldwide dissemination of MDROs, fundamental questions remain regarding the burden of resistance, metrics to measure prevalence, and determinants of spread. We describe a multi-site colonization survey protocol that aims to quantify the population-based prevalence and associated risk factors for colonization with high-threat MDROs among community dwelling participants and patients admitted to hospitals within a defined population-catchment area.MethodsResearchers in five countries (Bangladesh, Chile, Guatemala, Kenya, and India) will conduct a cross-sectional, population-based prevalence survey consisting of a risk factor questionnaire and collection of specimens to evaluate colonization with three high-threat MDROs: extended-spectrum cephalosporin-resistant Enterobacteriaceae (ESCrE), carbapenem-resistant Enterobacteriaceae (CRE), and methicillin-resistant Staphylococcus aureus (MRSA). Healthy adults residing in a household within the sampling area will be enrolled in addition to eligible hospitalized adults. Colonizing isolates of these MDROs will be compared by multilocus sequence typing (MLST) to routinely collected invasive clinical isolates, where available, to determine potential pathogenicity. A colonizing MDRO isolate will be categorized as potentially pathogenic if the MLST pattern of the colonizing isolate matches the MLST pattern of an invasive clinical isolate. The outcomes of this study will be estimates of the population-based prevalence of colonization with ESCrE, CRE, and MRSA; determination of the proportion of colonizing ESCrE, CRE, and MRSA with pathogenic characteristics based on MLST; identification of factors independently associated with ESCrE, CRE, and MRSA colonization; and creation an archive of ESCrE, CRE, and MRSA isolates for future study.DiscussionThis is the first study to use a common protocol to evaluate population-based prevalence and risk factors associated with MDRO colonization among community-dwelling and hospitalized adults in multiple countries with diverse epidemiological conditions, including low- and middle-income settings. The results will be used to better describe the global epidemiology of MDROs and guide the development of mitigation strategies in both community and healthcare settings. These standardized baseline surveys can also inform future studies seeking to further characterize MDRO epidemiology globally.

Mortality associated with third generation cephalosporin-resistance in Enterobacteriaceae infections: a multicenter cohort study in Southern China

ABSTRACT Background: Emerging third-generation cephalosporin-resistant Enterobacteriaceae (3GCR-EB) pose global healthcare concern. This study assessed the in-hospital mortality attributed to 3GCR-EB. Methods: The study cohort comprised inpatients with community-onset or healthcare-associated infection caused by Enterobacteriaceae in three tertiary-care public hospitals in 2017. In-hospital mortality was compared between 3GCR-EB infected patients and third-generation cephalosporin-susceptible Enterobacteriaceae (3GCS-EB) infected patients using competing risk survival models. Results: Of 2,343 study patients (median age 60 years; 45.2% male), 1,481 (63.2%) had 3GCS-EB and 862 (36.8%) 3GCR-EB infection. 494 (57.0%) 3GCR-EB isolates were co-resistant to fluoroquinolones and 15 (1.7%) to carbapenems. In-hospital mortality was similar in 3GCS-EB and 3GCR-EB infections (2.4% vs. 2.8%; p = 0.601). No increase in the hazard of in-hospital mortality was detected for 3GCR-EB compared to 3GCS-EB infection (sub-distribution hazard ratio [HR] 0.80; 95%CI, 0.41–1.55) adjusting for patient age, sex, intensive care admission, origin of infection and site of infection. Analysis of cause-specific hazards showed that 3GCR-EB infections significantly decreased the daily rate of hospital discharge (cause-specific HR = 0.84; 95%CI, 0.76–0.92) leading to lengthier hospitalizations. Conclusion: 3GCR-EB infection per se was not associated with increased in-hospital mortality in this study, but placed significant healthcare burden by increasing the length of hospitalization.

Antibiotic use and prescription and its effects on Enterobacteriaceae in the gut in children with mild respiratory infections in Ho Chi Minh City, Vietnam. A prospective observational outpatient study.

Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. Patients were prospectively enrolled in Children's Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients' urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422.

The Implementation of Active Environmental Surveillance in a Veterinary Referral Hospital Setting

Emily Feyes, The Ohio State University College of Veterinary Medicine; Dixie Mollenkopf, The Ohio State University College of Veterinary Medicine; Thomas Wittum, The Ohio State University College of Veterinary Medicine; Dubraska Diaz-Campos, The Ohio State University College of Veterinary Medicine; Rikki Horne, The Ohio State University College of Veterinary MedicineBackground: The Ohio State University College of Veterinary Medicine (OSU-CVM) Antimicrobial Stewardship Working Group (ASWG) uses monthly environmental surveillance to understand the effectiveness of our veterinary medical center (VMC) infection control and biosecurity protocols in reducing environmental contamination with multidrug resistant organisms. Monthly surveillance allows us to monitor trends in the recovery of these resistant organisms and address issues of concern that could impact our patients, clients, staff, and students. Methods: The OSU-CVM ASWG collects samples from &gt;100 surfaces within the companion animal, farm animal, and equine sections of our hospital each month. Sampling has been continuous since January 2018. Samples are collected from both human–animal contact and human-only contact surfaces using Swiffer electrostatic cloths. These samples are cultured for recovery of Salmonella spp, extended-spectrum cephalosporin-resistant Enterobacteriaceae, carbapenemase-producing Enterobacteriaceae (CPE), and methicillin-resistant Staphylococcus spp. Results: The recovery of these antibiotic resistant target organisms is low in the environment of our hospital. Recovery from human-only contact surfaces (19.8%) is very similar to recovery from human–animal contact surfaces (25.5%). We commonly recover Enterobacteriaceae (E.coli, Klebsiella spp, and Enterobacter spp) that are resistant to extended-spectrum cephalosporins (496 of 2,016; 24.6%) from the VMC environment. These antibiotic-resistant indicator bacteria are expected in a veterinary hospital setting where use the of β-lactam drugs is common. Recovery of both Salmonella spp and CPE has remained very low in our hospital environment over the past 19 months: 16 of 2,016 (0.7%) for Salmonella and 15 of 2,016 (0.8%) for CPE. Discussion: The active environmental surveillance component of our antimicrobial stewardship program has allowed us to reduce the threat of nosocomial infections within our hospital and address environmental contamination issues before they become a problem. Our consistently low recovery of resistant organisms indicates the effectiveness of our existing cleaning and disinfection protocols and biosecurity measures. Due to the nature of our patient population, we do expect to find resistant organisms in the patient-contact areas of the hospital environment. However, our similar rates of resistant organisms from human-only surfaces (eg, computer keyboards, door handles, telephones, and Cubex machines) indicates a need to improve our hand hygiene practices. These data are now supporting the implementation of a new hand hygiene campaign in our veterinary hospital.Funding: NoneDisclosures: None

Third-generation cephalosporin resistant Enterobacteriaceae in neonates and young infants: impact and outcome

Objective Third-generation cephalosporins resistant Enterobacteriaceae (3GCR-EB) are a major threat in severely ill neonates hospitalized in Neonatal Intensive Care Units. Still, the particular impact of 3GCR-EB on outcomes in the wide neonatal population is not well-appreciated. We aimed to study the impact of 3GCR-EB on the length of hospital stay and mortality of a general population of neonates and young infants. Study design This was a retrospective cohort study of neonates and young infants born in eight Israeli hospitals between 2009 and 2013, with a culture taken within three months after birth that tested positive for Enterobacteriaceae (EB). Data for this study were taken from centralized electronic health records included inpatient, outpatient, socio-demographic, administrative and laboratory information. The main outcomes were length of stay and mortality. The main explanatory variable was an isolation of 3GCR-EB in any bacterial culture taken from a neonate or young infant. Results Cultures were taken for 31,921 neonates and young infants; 2647 (8.3%) tested positive for EB and 290 (11%) tested positive for 3GCR-EB. Length of stay for those who tested positive was 2.8 times longer (95%CI: 2.70–2.91, p ˂ .001) than patients who tested positive for 3GC-susceptible EB. 3GCR-EB were also associated with increased mortality (OR: 12.06, 95%CI: 4.92–32.29). Conclusions Neonates with third-generation cephalosporins resistant Enterobacteriaceae had extended hospitalization and increased mortality, which was mostly significant in normal gestational weight newborns.

Risks and burdens of third-generation cephalosporin resistant Enterobacteriaceae in neonatal sepsis.

Third-generation cephalosporin resistant Enterobacteriaceae (TCRE) is a global concern especially in neonatal sepsis. We performed a secondary data analysis in a Thai neonatal intensive care unit to identify the risk factors for acquisition of TCRE sepsis and mortality of Enterobacteriaceae sepsis between 1991 and 2017. Multivariate logistic and Cox proportional regression were used for analysis. Numbers of neonates with TCRE and nonTCRE sepsis were 100 and 41 patients, respectively. Medians (interquartile ranges) of gestational age, birthweight, onset of sepsis and total hospital stay of neonates with Enterobacteriaceae sepsis were 32 (28, 38) weeks, 1670 (1025, 2750) grams, 11 (6, 25) days and 41 (22, 74) days, respectively. Univariate and multivariate analysis, neonates with TCRE sepsis were more likely to have birth asphyxia (adjusted odds ratio [aOR] = 2.6; 95% confidence interval [CI] 1.1-6.0; p = 0.02) and history of aminoglycoside exposure (aOR = 2.9; 95% CI 1.3- 6.7; p = 0.01). In-hospital case fatality rate from Enterobacteriaceae sepsis was 26% (36/141). In Cox regression, neonates with TCRE sepsis was not an independent risk of non-survivors, but septic shock (adjusted hazard ratio = 9.9; 95% CI 5.0-19.7, p < 0.001) increased 30-day mortality in the final model. Asphyxia and previous aminoglycoside consumption were risks of acquisition for neonatal TCRE sepsis while the burden was not a significant difference. Infection prevention and control must be strictly implemented in high multidrug-resistant area.

High Prevalence and Diversity of Cephalosporin-Resistant Enterobacteriaceae Including Extraintestinal Pathogenic E. coli CC648 Lineage in Rural and Urban Dogs in Northwest Spain.

The aim of this work was to assess the prevalence of extended spectrum-β-lactamase (ESBL)- and carbapenemase-producing Enterobacteriaceae in fecal samples recovered from rural and urban healthy dogs in Northwest Spain (Galicia) to identify potential high-risk clones and to molecularly characterize positive isolates regarding the genes coding for ESBL/pAmpC resistance and virulence. Thirty-five (19.6%) out of 179 dogs were positive for cephalosporin-resistant Enterobacteriaceae, including Escherichia coli and Klebsiella pneumoniae (39 and three isolates, respectively). All the isolates were multidrug resistant, with high rates of resistance to different drugs, including ciprofloxacin (71.4%). A wide diversity of ESBL/pAmpC enzymes, as well as E. coli phylogroups (A, B1, C, D, E, F and clade I) were found. The eight isolates (20.5%) found to conform to the ExPEC status, belonged to clones O1:H45-clade I-ST770 (CH11-552), O18:H11-A-ST93-CC168 (CH11-neg), O23:H16-B1-ST453-CC86 (CH6-31), and O83:H42-F-ST1485-CC648 (CH231-58), with the latter also complying the uropathogenic (UPEC) status. The three K. pneumoniae recovered produced CTX-M-15 and belonged to the ST307, a clone previously reported in human clinical isolates. Our study highlights the potential role of both rural and urban dogs as a reservoir of high-risk Enterobacteriaceae clones, such as the CC648 of E. coli and antimicrobial resistance traits. Within a One-Health approach, their surveillance should be a priority in the fight against antimicrobial resistance.

Effectiveness and safety of an institutional aminoglycoside-based regimen as empirical treatment of patients with pyelonephritis.

To determine clinical outcomes associated with aminoglycosides versus other antimicrobial agents as empirical treatment of hospitalized patients with pyelonephritis. An institutional programme promoting aminoglycosides as empirical treatment of pyelonephritis was implemented in 2016. We reviewed the hospital records of patients with pyelonephritis from January 2017 to April 2019. The primary outcome was death within 30 days of index culture. Initial treatment with aminoglycoside-based regimens was compared with non-aminoglycoside antibiotics. Propensity score matching was performed to adjust for between-group differences in baseline covariates. The study cohort included 2026 patients, 715 treated with aminoglycosides and 1311 treated with non-aminoglycoside drugs (ceftriaxone, n = 774; piperacillin/tazobactam, n = 179; carbapenems, n = 161; and fluoroquinolones, n = 133); 589 patients (29%) had bloodstream infections. Treatment with aminoglycosides was associated with a higher likelihood of in vitro activity against clinical isolates (OR = 2.0; P < 0.001). Death at 30 days occurred in 55 (7.6%) versus 145 (11%) patients treated with aminoglycosides and non-aminoglycoside drugs, respectively (adjusted HR = 0.78; P = 0.013). Aminoglycosides were either superior or similar to comparator drugs in all patient subgroups, stratified according to age, glomerular filtration rate, bacteraemia, haemodynamic shock and infection with third-generation cephalosporin-resistant Enterobacteriaceae. The incidence of acute kidney injury was similar for aminoglycosides and comparators (2.5% versus 2.9%, respectively; P = 0.6). Within the context of an institutional programme, initial empirical treatment of pyelonephritis with aminoglycosides was associated with higher rates of in vitro activity and lower overall mortality compared with non-aminoglycoside drugs, without excess nephrotoxicity.