Resistant Enterobacteriaceae Research Articles

2056. Trends in the Rates of Multidrug-resistant Bacteria Commonly Associated with Healthcare in U.S. Acute Care Hospitals, 2019-June 2021

Abstract Background Several studies demonstrated an increase in hospital-onset (HO) infections during the COVID-19 pandemic. We examined trends in the rates of multidrug-resistant (MDR) infections among acute care hospitals in the United States (U.S.) for bacteria commonly associated with healthcare: methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum cephalosporin resistance in Enterobacteriaceae suggestive of extended-spectrum beta-lactamase production (ESBL), vancomycin resistant Enterococcus (VRE), MDR Pseudomonas aeruginosa, carbapenem resistant Enterobacteriaceae (CRE), and carbapenem-resistant Acinetobacter species (CRAB). Methods We measured incidence of clinical cultures yielding the bacterial species of interest among hospitalized patients in a dynamic cohort of hospitals submitting data to the Premier Healthcare Database Special COVID-19 Release during 2019-June 2021. Community-onset (CO) cultures were obtained ≤ day 3 of hospitalization; HO were obtained ≥ day 4. We determined monthly hospital-specific rates for each species. We used generalized estimating equations (GEE) multivariable negative binomial regression models adjusting for hospital characteristics to examine trends. Results From 2019-June 2021, the overall number of hospitals contributing data was 318. Rates for each pathogen are shown in Figures 1 and 2. All pathogens’ HO rates were significantly higher in 2021 compared with 2019. The rates of ESBL, VRE, and CRE were also significantly higher in 2021 when compared to 2020 (Table 1a). For CO rates, we found that MRSA rates decreased significantly during the study period, while ESBL, VRE, and CRE increased with varying degree of significance (Table 1b). Rates of CO MDR Pseudomonas and CO CRAB did not significantly change. Conclusion Our study confirmed that the rates of several MDR infections increased during the COVID-19 pandemic through June 2021, especially HO infections. CO MRSA was the only pathogen with consistent and significant decline. As infections caused by MDR pathogens represent a serious threat to patient safety, further study of factors contributing to the emerging trends may inform prevention strategies during a pandemic. Disclosures All Authors: No reported disclosures.

First report of Molecular Epidemiology of Carbapenem Resistant Enterobacteriaceae from a Tertiary Level Hospital in Rajasthan, Western India

Background: Carbapenem Resistant Enterobacteriaceae (CRE) are emerging at an alarming rate and pose a significant global threat. Objective: To conduct phenotypic and genotypic characterization of CRE strains from Rajasthan, Western India. Methodology: This was a prospective observational study conducted in Department of Microbiology, Dr S.N. Medical College, Jodhpur, Rajasthan from October to December 2018. All clinical samples received during the study period were processed and bacterial identification and antimicrobial susceptibility tests were performed according to standard microbiological guidelines. A total of 14 non duplicate carbapenem resistant clinical isolates of E coli and K pneumoniae were included in the study and subjected to Rapidec Carba NP test. Carbapenemase‑ encoding genes were amplified by multiplex polymerase chain reaction (PCR). PCR amplified products from three random isolates were subjected to Sanger sequencing. Results: Amikacin remained active against 36% isolates. All isolates were found to be susceptible to colistin and tigecycline. Carbapenemase production by Rapidec Carba NP test was noted in all (14/14) study isolates. All isolates were found to harbour ≥ 1 carbapenemase gene. The most common resistance gene observed was blaoxa (86%) followed by blaNDM (79%). None of the CRE isolates included in our study showed production of KPC enzymes. The sequences were analysed using BLAST analysis and were confirmed to be matching to OXA-48/181 and NDM-1. Conclusions: Growing carbapenem resistance is an important issue which needs urgent attention and blaOXA is an emerging mechanism of resistance among clinical CRE isolates in our setting Keywords: Carbapenem resistant Enterobacteriaceae, Phenotypic tests, Carbapenemase gene, Polymerase chain reaction

Multidrug resistance-encoding gene in Citrobacter freundii isolated from healthy laying chicken in Blitar District, Indonesia

Background and Aim: The increasing prevalence of resistance (MDR) of Enterobacteriaceae in Indonesia has caused concern regarding human health. Citrobacter freundii reportedly targets the gastrointestinal tract of animals and is a common cause of foodborne diseases associated with diarrhea, peritonitis, meningitis, brain abscess, bacteremia, and urinary tract infection. This study aimed to estimate the prevalence of MDR and the presence of Class 1 integron-encoding genes in C. freundii isolates obtained from cloacal swabs of healthy laying chickens in Blitar district, Indonesia. Materials and Methods: One hundred and sixty-five cloacal swab samples were collected from 33 farms in Blitar over a period of 4 months. Standard microbiological techniques such as bacterial culture in MacConkey agar, Simmons citrate agar, and triple sugar iron agar and biochemical tests such as the indole test were performed to identify the isolates. The antibiotic sensitivity patterns of C. freundii isolates were determined by the disk diffusion method, and MDR-encoding genes (Class 1 integron) were detected by polymerase chain reaction (PCR). Results: Out of 165 cloacal swab samples, 7 (4.24%) were positive for C. freundii. Citrobacter freundii was highly resistant to erythromycin (71.43%) and moderately to streptomycin, tetracycline, and trimethoprim-sulfamethoxazole (all 42.86%); however, it showed low resistance to ampicillin (28.57%). All isolates were found to exhibit MDR. Only 1 (14.29%) of the seven C. freundii isolates harbored a Class 1 integron gene. This study revealed that Class 1 integron-encoding genes have a low prevalence in C. freundii isolated from healthy laying chickens in Blitar, Indonesia. Conclusion: Poultry animals can play a role in the transmission of resistance genes to humans due to the MDR of Enterobacteriaceae, including C. freundii in the intestines.

Zinc Oxide Nanoflakes Mechanism of Action: A Future Prospective Nanomedicine Against CRE Infections

The emergence and spread of carbapenem-hydrolysing beta-lactamases among Enterobacteriaceae and Non-fermentative Gram-negative bacilli organisms like Pseudomonas spp. or Acinetobacter baumannii over the past ten years is a serious problem in hospital settings. This problem has been exacerbated by the fact that carbapenems are no longer as effective against these pathogens. Aside from that, numerous bacteria in the natural environment form biofilms. When opportunistic biofilm-forming pathogens cause infections, they can cause severe symptoms in many cases and death in people who don't have strong immune systems. No new class of antibiotic have been reported in the last several decades. In this context, Recent years have seen a rise in the importance of nanobiotechnology in the production of nanomaterials that function as antibacterial agents. It is possible for nanoparticles to be active molecules or compounds that react with bacterial cells to kill them. This has the potential to resolve issues associated with multidrug resistance and inhibit biofilm. In the present study, synthesized ZnO nanoflakes were utilized. These nanoflakes had an average crystallite size of 21.5 ± 4.8 nm, a thickness of 20-50 nm, and different characteristics. We have included 67 Carbapenem resistant Enterobacteriaceae (CRE) and Non-fermentative Gram-negative bacilli isolates, which were isolated from various clinical samples. ZnO-NPs showed strong antibacterial and antibiofilm action against clinical isolates, according to growth kinetics and antibiofilm assay. In addition, we looked into how ZnO-NPs interact with clinical bacterial strains to determine their mode of action. ZnO is thought to exert its effects via reactive oxygen species (ROS) production, which boosts membrane lipid peroxidation and ultimately results in the loss of reducing sugars through membrane leakage. These findings suggest that in future ZnO-NPs might be an effective alternate treatment of choice to treat infections caused by CR bacterial isolates.

Drug resistance profiles of Gram-negative bacilli isolated from clinical samples in Cross River State, Nigeria

Objectives: Resistance of Gram-negative bacilli (GNB) to antimicrobial agents is increasing worldwide. This is fast becoming a serious public health concern as these bacteria display multiple antibiotic resistance mechanisms. This study was aimed at evaluating antibiotic resistance profiles of GNB from clinical samples in Cross River State, Nigeria. Material and Methods: Urine and stool samples of 600 randomly selected participants were analyzed. Samples were inoculated onto CLED agar and selenite-F broth, respectively, and enriched bacterial growth in selenite-F broth was subcultured on deoxycholate citrate agar. Gram stain procedure was used to determine the Gram reaction of isolates and identification was carried out using the Microbact 24E GNB identification kit. Antibiotic susceptibility testing was performed using the Kirby–Bauer disk diffusion method. Multiple antibiotic resistance indices (MARIs) for each isolate were calculated. Data analysis was carried out using Microsoft Excel Package 2016 and GraphPad Prism version 6. Results: A total of 129 non-repetitive GNB were isolated and categorized by their ability to ferment sugars. The lactose-fermenting Enterobacteriaceae (LFE) were the most predominant isolates (32 Klebsiella pneumoniae and 25 Escherichia coli). There were 50 non-sugar-fermenting Gram-negative bacilli (NSF-GNB) comprising Pseudomonas spp. (28), Acinetobacter spp. (15), Burkholderia cepacia (3), and one isolate each of Tatumella ptyseos, Alcaligenes faecalis, Aeromonas hydrophila, and Stenotrophomonas maltophilia. Non-lactose-fermenting Enterobacteriaceae comprised Proteus spp. (14), Providencia stuartii (4), and Serratia rubidaea (4). Antimicrobial susceptibility test results showed that tetracycline was the least effective with 71.3% of isolates showing resistance. About 65% of LFE and 95.5% of non-lactose-fermenting Enterobacteriaceae (NLFE) showed resistance to tetracycline. Resistance of all isolates to tigecycline, a member of a new class of antibiotics, was 31% (40/129); however, all isolates of E. coli, S. rubidaea, and Acinetobacter spp. were susceptible to tigecycline. Resistance profiles of LFE to tested antibiotics showed comparable resistance levels for ceftriaxone and tetracycline between K. pneumoniae and E. coli. However, the resistance of K. pneumoniae to ceftazidime, ciprofloxacin, and tigecycline was 50%, 44%, and 13% compared with E. coli – 32%, 32%, and 0%, respectively. E. coli showed, on average, higher resistance levels to carbapenems compared with K. pneumoniae. Among NLFE, Proteus spp. was more resistant than P. stuartii to cephalosporins, quinolones, and tigecycline. In contrast, P. stuartii isolates were twice as resistant to the carbapenems as Proteus spp. Except for ciprofloxacin, tetracycline, and gentamicin, S. rubidaea was susceptible to all other antibiotics. Among NSF-GNB, Acinetobacter spp. was the most resistant to all other carbapenems, except ertapenem. Pseudomonas spp. were the most resistant to fluoroquinolones. The mean of the total MARI was 0.45 ± 0.26, with 54.3% (70/129) of isolates having MARI above the total mean. About 73% (95/129) of the total GNB had MARI above 0.2. Multidrug resistance in Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter species was 53.2%, 100%, and 93.3%, respectively. Conclusion: The high level of antibiotic resistance of GNB, especially by NLFE and NSF-GNB, portends great danger for the health sector as these organisms are opportunistic pathogens and pose serious health risks as nosocomial pathogens and community-acquired pathogens in immunosuppressed individuals.

Investigating the Role of Antibiotics on Induction, Inhibition and Eradication of Biofilms of Poultry Associated Escherichia coli Isolated from Retail Chicken Meat.

Widespread use of antibiotics as growth promoters and prophylactic agents has dramatic consequences for the development of antibiotic resistance. In this study, we investigated effects of selected antibiotics on bacterial biofilms and performed extensive antibiotic and VF profiling of poultry-meat associated E. coli strains. Antibiotic susceptibility was performed by a disc diffusion method, followed by molecular screening of resistance and virulence determinants. Further biofilm formation assays, MIC-p, MIC-b, MBIC and MBEC, were performed using standard tissue culture plate method. In total, 83 (75%) samples were confirmed as E. coli from poultry sources, 26 different antibiotics were tested, and maximum numbers of the isolates were resistant to lincomycin (100%), while the least resistance was seen against cefotaxime (1%) and polymyxin B (1%). Overall, 48% of the isolates were ESBL producers and 40% showed carbapenemase activity; important virulence genes were detected in following percentages: fimH32 (39%), papC21 (25%), iutA34 (41%), kpsMT-II23 (28%), papEF9 (11%), papGII22 (27%) and fyuA13 (16%). Colistin showed remarkable anti-biofilm activity, while at sub-MIC levels, gentamicin, ceftriaxone and enrofloxin significantly (p < 0.01) inhibited the biofilms. A strong induction of bacterial biofilm, after exposure to sub-minimal levels of colistin clearly indicates risk of bacterial overgrowth in a farm environment, while use of colistin aggravates the risk of emergence of colistin resistant Enterobacteriaceae, a highly undesirable public health scenario.

A cross-sectional study of the antibiotic resistant prevalence of ESBL-producing Enterobacteriaceae in Vietnam

Introduction: Antibiotic resistance in Enterobacteriaceae producing extended spectrum beta-lactamase (ESBL) is increasing. Accurate evaluation of antibiotic resistance rates in various categories of bacteria assists medical physicians in recommending suitable indications for their medical problems, improving treatment efficiency, and minimizing dangers for patients. As a result, we undertook this research to assess the prevalence of ESBL-producing Enterobacteriaceae as well as the rate of antibiotic resistance in ESBL-producing Enterobacteriaceae. Methods: A cross-sectional study was conducted on 2716 patients at the An Giang Central General Hospital from June 2020 to June 2021. Data collection was based on interviews and used SPSS 18.0 and GraphPad Prism 9 for data analysis and presentation. Samples included urine, blood, sputum, and pus. Samples were treated with the Phoenix 100 automated machine to separate and identify samples. Results: The highest rate was 64.8% for Escherichia coli, followed by 30.2% for Klebsiella pneumoniae. Proteus mirabilis and Klebsiella oxytoca were found in 4.5% and 0.6% of the samples, respectively. Ampicillin resistance was greatest in E. coli (96.5%), K. pneumonia (92.4%), and K oxytoca (83.3%). The frequency of resistance to the other antibiotics was likewise extremely high, approaching 60%. Tobramycin, Amoxicillin/Clavulanate, Cefoxitin, and Nitrofurantoin were totally resistant to K. oxytoca in the ESBL-producing group. E. coli and K. pneumoniae with ESBL-producing genes also have a high antibiotic resistance rate of more than 50%. Conclusion: E. coli was the most common pathogenic bacteria. Most of the species of bacteria resisted Ampicillin.

Incidence of Drug-Resistant Enterobacteriaceae Strains in Organic and Conventional Watermelons Grown in Tennessee.

The production and consumption of organic fresh produce have constantly increased since the 1990s. Consumers prefer organic produce because it does not contain synthetic chemical residues that are often implicated in health problems. The contamination of fresh produce by pathogenic Enterobacteriaceae strains remains a major challenge, and is responsible for frequent foodborne disease outbreaks. The use of antibiotics has proved an effective treatment, but the increase in occurrences of antibiotic resistance is becoming a health challenge. This study seeks to establish the presence of antimicrobial resistance in Enterobacteriaceae on organic and conventional watermelon fruits. Watermelons used for this study were cultivated at the Tennessee State University Certified Organic Farm, Nashville. At harvest, nine fruits were selected from among fruits lying on plastic mulch, and nine from fruits lying on the soil of both organic and conventional plots. These were placed in sterile sample bags for microbial analysis. Spread plating technique, API 20E, and apiweb software were used for microbial isolation and identification. Identified strains were tested for antimicrobial resistance against 12 common antibiotics. Seventeen Enterobacteriaceae strains were isolated and identified. Isolates were susceptible to gentamycin, ciprofloxacin, and chloramphenicol, but were resistant to cefoxitin. Citrobacter freundii showed a 14.3% resistance to Streptomycin. Pantoea spp. and Providencia rettigeri showed 50% and 100% resistance to tetracycline. Findings from this study confirm the presence of antibiotic-resistant Enterobacteriaceae strains on organic watermelons in Nashville, TN.

Invitro Activity of Tigecycline against Multidrug-Resistant Enterobacteriaceae from Blood Stream Infection in a Tertiary Care Hospital of Nepal

Background: Multidrug resistant (MDR) enterobacteriaceae like extended spectrum beta lactamase (ESBL) and metallo-beta lactamase (MBL) are being encountered as the causative agents of blood stream infection. To overcome this, accurate diagnosis of MDR pattern with appropriate antibiotics is required. Tigecycline is a broad spectrum antibiotic which exhibit strong activity against MDR enterobacteriaceae. This study is aimed to find out resistance pattern like ESBL and MBL with invitro activity of tigecycline against enterobacteriaceae. Methods: A descriptive cross-sectional study was conducted in the Department of Microbiology, B.P. Koirala Institute of Health Sciences, from 1st September 2014 to 31st August 2015. Confirmation for ESBL was done as recommended by Clinical and Laboratory Standard Institute (CLSI) and MBL production was detected by double disk synergy test. Antibiotic sensitivity test against tigecycline was done by Kirby-Bauer disk diffusion method. Results: 192 (1.70%) enterobacteriaceae were isolated throughout the study. Among them, 94 (49%) were ESBL, 51 (26.5%) were carbapenemase and 22 (11.5%) were MBL producers. A total of 64 (33.4%) isolates were found to be MDR. None of the isolates was resistant against tigecycline. Conclusion: Tigecycline is found to have excellent invitro activity against MDR enterobacteriaceae from BSI.

Detection of an IMI-2 carbapenemase-producing Enterobacter asburiae at a Swedish feed mill.

Occurrence of multidrug resistant Enterobacteriaceae in livestock is of concern as they can spread to humans. A potential introduction route for these bacteria to livestock could be animal feed. We therefore wanted to identify if Escherichia spp., Enterobacter spp., Klebsiella spp., or Raoutella spp. with transferable resistance to extended spectrum cephalosporins, carbapenems or colistin could be detected in the environment at feed mills in Sweden. A second aim was to compare detected isolates to previous described isolates from humans and animals in Sweden to establish relatedness which could indicate a potential transmission between sectors and feed mills as a source for antibiotic resistant bacteria. However, no isolates with transferable resistance to extended-cephalosporins or colistin could be identified, but one isolate belonging to the Enterobacter cloacae complex was shown to be carbapenem-resistant and showing carbapenemase-activity. Based on sequencing by both short-read Illumina and long-read Oxford Nanopore MinIon technologies it was shown that this isolate was an E. asburiae carrying a bla IMI-2 gene on a 216 Kbp plasmid, designated pSB89A/IMI-2, and contained the plasmid replicons IncFII, IncFIB, and a third replicon showing highest similarity to the IncFII(Yp). In addition, the plasmid contained genes for various functions such as plasmid segregation and stability, plasmid transfer and arsenical transport, but no additional antibiotic resistance genes. This isolate and the pSB89A/IMI-2 was compared to three human clinical isolates positive for bla IMI-2 available from the Swedish antibiotic monitoring program Swedres. It was shown that one of the human isolates carried a plasmid similar with regards to gene content to the pSB89A/IMI-2 except for the plasmid transfer system, but that the order of genes was different. The pSB89A/IMI-2 did however share the same transfer system as the bla IMI-2 carrying plasmids from the other two human isolates. The pSB89A/IMI-2 was also compared to previously published plasmids carrying bla IMI-2, but no identical plasmids could be identified. However, most shared part of the plasmid transfer system and DNA replication genes, and the bla IMI-2 gene was located next the transcription regulator imiR. The IS3-family insertion element downstream of imiR in the pSB89A was also related to the IS elements in other bla IMI-carrying plasmids.

Drug Resistance Mechanism of Enterobacteriaceae with Decreased Antibiotic Sensitivity.

To investigate the mechanism of antibiotic resistance in Enterobacteriaceae. Carbapenem Enterobacteriaceae bacteria isolated from a hospital from January 2015 to June 2020 were selected. Drug resistance phenotype test, drug sensitivity test, and conjugation test were used to observe the drug sensitivity results and the titer of acrB antibody. Finally, the data were statistically analyzed. All strains were resistant to ceftazidime, ceftriaxone, ertapenem, and aztreonam. 87.5% of the samples were resistant to piperacillin. Multisite sequence typing showed that 5 carbapenem-resistant Klebsiella pneumoniae belonged to 4 different types. The sequence types of kpn6099 and kpn6617 were the same. In the sensitivity comparison, Escherichia coli J53 was more sensitive to these two antibiotics, minimum inhibitory concentration values were 0.5 and 0.25 μg/ml, respectively. In addition, the sensitivity of E. coli J53 to carbapenems was slightly higher than that of kpn6617. The results showed that the enzyme-linked immunosorbent assay titer of acrB antibody was 1:40,000, and the preparation of acrB antibody was successful. Plasmid-mediated deletion of IMP-1 metallo-β-lactamase binding outer membrane protein is one of the main reasons for the decrease of antibiotic sensitivity.

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.

Efficacy of empiric antibiotic treatment of late-onset neonatal sepsis caused by Enterobacteriaceae: A systematic review.

Neonatal sepsis is a serious condition, where an adequate empiric antibiotic treatment is crucial. The objective of this systematic review is to assess whether the World Health Organization's recommended treatment regime remains applicable for late-onset neonatal sepsis caused by Enterobacteriaceae, in the time of increased antimicrobial resistance. PubMed was searched for articles from 2009 to 2020. A total of 49 articles were eligible for inclusion. The review was carried out in accordance with PRISMA guidelines. For Klebsiella spp. 100, 68 and 63% of the studies found sensitivity to ampicillin, gentamicin and third-generation cephalosporin in <50% of the isolates. For Escherichia coli, the corresponding values were 88, 50 and 42% respectively, whilst for Enterobacter spp. 100, 70 and 94% of the studies found <50% sensitivity to these antibiotics. Overall, there is low sensitivity to all agents in the WHO's recommended empiric treatment regimes (WHO recommends ampicillin plus gentamicin as first-line treatment and third-generation cephalosporin as second-line treatment). A revised guideline for empiric antibiotic treatment of neonatal sepsis is urgently needed due to the increased threat of antimicrobial resistant Enterobacteriaceae causing neonatal sepsis.

Antimicrobial, Multi-Drug and Colistin Resistance in Enterobacteriaceae in Healthy Pigs in the Greater Accra Region of Ghana, 2022: A Cross-Sectional Study.

There is little published information on antimicrobial resistance (AMR) in animals in Ghana. We determined the prevalence and factors associated with AMR, multi-drug resistance (MDR-resistance to ≥3 antimicrobial classes) and colistin resistance in Enterobacteriaceae in healthy pigs in Accra, Ghana. Rectal swabs obtained from the pigs on 20 farms from January to March 2022, were examined for Escherichia coli, Enterobacter spp. and Klebsiella pneumoniae. AMR was determined using standard microbiological techniques and the mcr-1 gene detected through molecular analysis. Enterobacteriaceae were isolated from 197 of 200 pigs: these comprised 195 E. coli isolates, 38 Enterobacter spp. and 3 K. pneumoniae, either singly or combined. Over 60% of E. coli were resistant to tetracycline, with 27% and 34% being resistant to amoxicillin/clavulanic acid and ampicillin, respectively; 23% of E. coli and 5% of Enterobacter spp. exhibited MDR phenotypes. Phenotypic colistin resistance was found in 8% of E. coli and Enterobacter spp., with the mcr-1 gene detected in half. Our study findings should be incorporated into on-going AMR, MDR and colistin resistance surveillance programs in Ghana. We further advocate for tailored-specific education for pig farmers on animal antimicrobial use and for strengthened regulatory policy on antimicrobial usage and monitoring in the animal production industry.

The diversity in antimicrobial resistance of MDR Enterobacteriaceae among Chinese broiler and laying farms and two mcr-1 positive plasmids revealed their resistance-transmission risk.

This research aimed to investigate the microbial composition and diversity of antimicrobial resistance genes (ARGs) found in Chinese broiler and layer family poultry farms. We focused on the differences in resistance phenotypes and genotypes of multidrug-resistant Enterobacteriaceae (MDRE) isolated from the two farming environments and the existence and transmissibility of colistin resistance gene mcr-1. Metagenomic analysis showed that Firmicutes and Bacteroides were the dominant bacteria in broiler and layer farms. Many aminoglycoside and tetracycline resistance genes were accumulated in these environments, and their absolute abundance was higher in broiler than in layer farms. A total of 526 MDRE were isolated with a similar distribution in both farms. The results of the K-B test showed that the resistance rate to seven antimicrobials including polymyxin B and meropenem in broiler poultry farms was significantly higher than that in layer poultry farms (P ≤ 0.05). PCR screening results revealed that the detection rates of mcr-1, aph(3’)Ia, aadA2, blaoxa–1, blaCTX–M, fosB, qnrD, sul1, tetA, and catA1 in broiler source MDRE were significantly higher than those in layers (P ≤0.05). A chimeric plasmid p20432-mcr which carried the novel integron In1866 was isolated from broiler source MDRE. The high frequency of conjugation (10–1 to 10–3) and a wide range of hosts made p20432-mcr likely to play an essential role in the high detection rate of mcr-1, aph(3’)-Ia, and aadA2 in broiler farms. These findings will help optimize disinfection and improve antimicrobial-resistant bacteria surveillance programs in poultry farms, especially broilers.

In Vitro Activity of Single and Combined Antibiotics against Carbapenem Resistant Enterobacteriaceae Clinical Isolates in Relation to their Resistance Genes

Background: Mortality due to infection with carbapenem-resistant Enterobacteriaceae (CRE) is reported globally and carbapenemase production is the main mechanism of resistance in these isolates. The detection and treatment of carbapenemase-producing Enterobacteriaceae (CPE) is a major challenge in health care facilities.&#x0D; Objectives: The aim of the current study was to evaluate the in-vitro effect of different single and combined antibiotic agents against CRE clinical isolates.&#x0D; Methodology: Fifty CRE isolates were detected using disk diffusion test as a screening test. Species identification and antibiotic susceptibility testing was done using Vitek 2 system. Carbapenemase enzyme production was confirmed by Carba NP test. Multiplex PCR was done to detect carbapenem resistance genes. Antibiotics were tested in the form of single agents (colistin and tigecycline) and combined (tigecycline/ colistin, doripenem/ colistin and dual carbapenem therapy (ertapenem and doripenem) against CRE isolates using E-test method.&#x0D; Results: Most of the CRE isolates were K. pneumoniae, 68%, followed by E. coli, 22%, S. marcescens, 4%, E. cloacae, 4% and C. freundii, 2%. CPE was confirmed in 46 isolates by multiplex PCR; blaNDM-like was the main carbapenem resistance gene in (84%) of the isolates, followed by blaOXA-48-like (6%) and blaKPC-like (2%). Carba NP test detected 90% of CPE isolates. Single use of colistin and tigecycline showed 100% sensitivity against all tested CRE isolates except in blaNDM-like (83%). Combination of colistin/tigecycline showed synergetic activity in 18% of CRE that was correlated to their carbapenemase R genes showing a significant increase in blaOXA-48-like and blaKPC-like positive isolates (100%) compared to blaNDM-like (7%). Other combinations showed indifferent effect whereas antagonism was not detected in any of the tested combinations.&#x0D; Conclusions: blaNDM-like is the main carbapenemase-producing gene detected among our CPE isolates followed by blaOXA-48-like. Colistin and tigecycline are still effective when used as single agents, and may offer effective treatment options when used in combination for CRE infections. Characterization of carbapenemases is crucial in determining treatment options. There is urgent demand for the development of novel therapeutic agents against NDM-producing CPE isolates.

Antimicrobial Resistance of Enterobacteriaceae in Bloodstream Infections in Hospitalized Patients in Southern Poland

Aim: The aim of this study was to highlight antimicrobial resistance among Enterobacteriaceae isolated from bloodstream infections in hospitals in southern Poland. Materials and Methods: The present study includes laboratory-confirmed secondary bloodstream infections (LC-BSIs), in the years 2015–2018, in hospitalized adult patients (≥18). Episodes of BSIs were defined according to the strictly described guidelines. Antimicrobial susceptibility testing was performed with the automated system and the disc diffusion method. Extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriaceae were detected using the double-disc synergy test. Results: Between 2015 and 2018, 356 episodes of secondary BSIs in 997 patients aged 21–96 years were documented in a prospective study, including 134 (37.6%) ESBL-producing Enterobacteriaceae. Escherichia coli was the predominant pathogen in internal medicine (37.6%) and surgery units (46.8%); in intensive care units (ICUs), Klebsiella pneumoniae was isolated more frequently (33.3%). Enterobacteriaceae were highly resistant to most antimicrobial agents. K. pneumoniae isolates had a higher level of resistance than E. coli, regardless of the unit. Conclusions: The increase in AMR and the widespread distribution of ESBL-producing Enterobacteriaceae in Polish hospitals can be related to the lack of or inappropriate antibiotic treatment.

Evaluation of Bi-Lateral Co-Infections and Antibiotic Resistance Rates among COVID-19 Patients in Lahore, Pakistan.

Background and Objective: Bacterial infections are among the major complications of many viral respiratory tract illnesses, such as influenza and coronavirus disease-2019 (COVID-19). These bacterial co-infections are associated with an increase in morbidity and mortality rates. The current observational study was conducted at a tertiary care hospital in Lahore, Pakistan among COVID-19 patients with the status of oxygen dependency to see the prevalence of bacterial co-infections and their antibiotic susceptibility patterns. Materials and Methods: A total of 1251 clinical samples were collected from already diagnosed COVID-19 patients and tested for bacterial identification (cultures) and susceptibility testing (disk diffusion and minimum inhibitory concentration) using gold standard diagnostic methods. Results: From the total collected samples, 234 were found positive for different bacterial isolates. The most common isolated bacteria were Escherichia coli (E. coli) (n = 62) and Acinetobacter baumannii (A. baumannii) (n = 47). The E. coli isolates have shown the highest resistance to amoxicillin and ampicillin, while in the case of A. baumannii, the highest resistance was noted against tetracycline. The prevalence of methicillin resistant Staphylococcus aureus (MRSA) was 14.9%, carbapenem resistant Enterobacteriaceae (CRE) was 4.5%, and vancomycin resistant Enterococcus (VRE) was 3.96%. Conclusions: The results of the current study conclude that empiric antimicrobial treatment in critically ill COVID-19 patients may be considered if properly managed within institutional or national level antibiotic stewardship programs, because it may play a protective role in the case of bacterial co-infections, especially when a patient has other AMR risk factors, such as hospital admission within the previous six months.

Co-occurrence of blaNDM-1 and blaOXA-48 among carbapenem resistant Enterobacteriaceae isolates causing bloodstream infections in Alexandria, Egypt

Co-occurrence of blaNDM-1 and blaOXA-48 among carbapenem resistant Enterobacteriaceae isolates causing bloodstream infections in Alexandria, Egypt

Preadmission checklist by nursing staff for timely implementation of isolation precautions to prevent spread of infection in a paediatric transplant centre

Introduction: Hematopoietic stem cell transplant patients are at a high risk of infections because of prolonged neutropenia and lymphopenia.[1] Bacteraemia caused by enteric organisms is well known but they can have prolonged shedding of upper respiratory tract viruses and progression to pneumonia.[2] These organisms are spread via direct contact and nosocomial spread has been reported. Aim: Retrospective analysis of children transplanted in last three years after pre-admission checklist was implemented. Method: A pre-admission checklist of 3 infection control components was formulated. The protocol involved informing the nurse in-charge of admission for transplant and handing over all infection reports by on call fellow to nurses prior to admission. Isolation precautions were planned by nurses. Nasopharyngeal swab was sent on admission to the unit and droplet, or airborne precautions are instituted based on reports. Surveillance cultures were sent weekly for CRE (Carbapenem resistant Enterobacteriaceae and Nasopharyngeal swab was sent when child has symptoms. Result: 61 patients were analysed post institution of the checklist. 15 patients had respiratory organisms (viruses, streptococcus pneumoniae), 36 patients were positive for CRE and 2 for Methicillin resistant staphylococcus aureus in nasal swab. No respiratory organisms were transmitted. Surveillance cultures showed one suspected cross transmission of CRE. No outbreaks were reported. Conclusion: Respiratory viral illness are associated with high morbidity with limited management options. Strict adherence to infection control measures is important to preventing outbreaks in the transplant unit. Spread of multi-drug resistant organism puts patients at high risk of developing subsequent infections with them, increasing morbidity and mortality. A simple pre-admission checklist can ensure adequate early isolation and prevent spread of infections in this severely immunocompromised cohort.