Prevalence of multidrug-resistant extended spectrum beta-lactamase-producing Salmonella strains in commercial raw chicken meat

The incidence of extended spectrum beta-lactamase (ESBL)-producing pathogens is worrisome because it confers multiple drug resistance (MDR). Considering their serious clinical significance, the study investigated the prevalence of MDR-ESBL-producing Salmonella strains isolated from raw chicken meat in Southern Nigeria. A total of 240 raw chicken meat were sampled and the recovered Salmonella strains were characterized for MDR and ESBL-genes using Kirby Bauer disc diffusion and molecular techniques. Of the 52 confirmed Salmonellaenterica serotypes, 67.31% (35/52) were Salmonella entericasubsp. entericaserovar Typhimurium, 32.68% (17/52) were Salmonella entericasubsp. entericaserovar Enteritidis, 78.85% (41/52) were ESBL-producer and 88.45% (46/52) multidrug resistant. Ampicillin (96.15%) and gentamycin (40.39%) were the most and least antibiotics. The most prevalent MDR-ESBL-genes were bla CTX-M (92.68%), followed by bla SHV genes (68.29%) and bla TEM(31.71%). This study showed that Salmonella serotypes with high ESBL-genes and MDR were prevalent in raw chicken meat vended in southern Nigerian markets. Bangladesh J. Sci. Ind. Res.56(4), 271-284, 2021

Emergence of the New KPC-49 Variant Conferring an ESBL Phenotype with Resistance to Ceftazidime-Avibactam in the ST131-H30R1 Escherichia coli High-Risk Clone

We report the emergence of an isolate belonging to the sequence type (ST)131-Escherichia coli high-risk clone with ceftazidime-avibactam resistance recovered from a patient with bacteremia in 2019. Antimicrobial susceptibility was determined and whole genome sequencing (Illumina-NovaSeq6000) and cloning experiments were performed to investigate its resistance phenotype. A KPC-3-producing E. coli isolate susceptible to ceftazidime-avibactam (MIC = 0.5/4 mg/L) and with non-wild type MIC of meropenem (8 mg/L) was detected in a blood culture performed at hospital admission. Following 10-days of standard ceftazidime-avibactam dose treatment, a second KPC-producing E. coli isolate with a phenotype resembling an extended-spectrum β-lactamase (ESBL) producer (meropenem 0.5 mg/L, piperacillin-tazobactam 16/8 mg/L) but resistant to ceftazidime-avibactam (16/4 mg/L) was recovered. Both E. coli isolates belonged to ST131, serotype O25:H4 and sublineage H30R1. Genomics analysis showed a core genome of 5,203,887 base pair with an evolutionary distance of 6 single nucleotide polymorphisms. A high content of resistance and virulence genes was detected in both isolates. The novel KPC-49 variant, an Arg-163-Ser mutant of blaKPC-3, was detected in the isolate with resistance to ceftazidime-avibactam. Cloning experiments revealed that blaKPC-49 gene increases ceftazidime-avibactam MIC and decreases carbapenem MICs when using a porin deficient Klebsiella pneumoniae strain as a host. Both blaKPC-3 and blaKPC-49 genes were located on the transposon Tn4401a as a part of an IncF [F1:A2:B20] plasmid. The emergence of novel blaKPC genes conferring decreased susceptibility to ceftazidime-avibactam and resembling ESBL production in the epidemic ST131-H30R1-E. coli high-risk clone presents a new challenge in clinical practice.

Extended-Spectrum β-Lactamases in Human Isolates of Multidrug-Resistant Non-typhoidal Salmonella enterica

A total of 291 non-duplicate isolates of non-typhoidal Salmonella (NTS) were collected from the fecal samples of patients with salmonellosis in Armenia and Georgia during 1996–2016. The isolates were tested for resistance to antimicrobials, including extended-spectrum β-lactamases (ESBL). The high prevalence of multidrug-resistance (MDR) and ESBL-producer phenotypes was detected among Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) isolates collected from patients in Armenia between 1996 and 2016. A total of 36 MDR NTS isolates were subjected to whole genome sequencing (WGS) to determine the genetic background of antimicrobial resistance (AMR) and mobile genetic elements. All ESBL-producing S. Typhimurium isolates belonged to the same sequence type (ST328). The ESBL-producer phenotype was associated with plasmid-encoded CTX-M-5 production. A range of other plasmids was associated with resistance to other antimicrobials, including the MDR phenotype.

The Epidemiological Pattern and Risk Factor of ESBL (Extended Spectrum Β-Lactamase) Producing Enterobacteriaceae in Gut Bacterial Flora of Dairy Cows and People Surrounding in Rural Area, Indonesia

Livestock would be a risk factor of resistant bacteria that impact on human health. Rural area with farms as major economic source has become a risk of the spread of the ESBL producing Enterobacteriaceae The aim of the study was to explore the distribution and risk factor of ESBL (extended-spectrum β-lactamase) producing Enterobacteriaceae in the gut bacterial flora of dairy cows and people surrounding farming area. Total of 204 fecal swab samples were collected, 102 from dairy cows and 102 from farmers. Samples were sub-cultured by streaking on MacConkey agar supplemented with 2 mg/L cefotaxime. The growing colonies were confirmed of the ESBL producer by Modified Double Disk Test (M-DDST) and identification of Enterobacteriaceae by biochemical test. ESBL genes were identified by PCR. ESBL producing bacteria were found 13.7% in dairy cows and 34.3% in farmers. ESBL producing Enterobacteriaceae in dairy cows were 6.9% and in farmers of 33.3%. Statistical analysis showed: Distribution of ESBL producing Enterobacteriaceae strain were insignificant among dairy cows and farmers while blaTEM distribution was significantly different (p= 0,035) and use of antibiotic was identified as a risk factor of colonization of ESBL producing Enterobacteriaceae in farmers (p= 0,007). Farmers had suspected as the source of ESBL producing Enterobacteriaceae based on higher prevalence. Further education of appropriate use of antibiotic need to enhance to control risk factor and prevent the colonization of ESBL producing Enterobacteriaceae

Escherichia coli Producing Extended-Spectrum β-lactamases (ESBL) from Domestic Camels in the Canary Islands: A One Health Approach

Objective: This work aimed to determine the carriage rate of ESBL-producing Escherichia coli as well as their genetic characteristics in camels from the Canary Islands, Spain. Methods: Fecal samples were recovered from 58 healthy camels from Gran Canaria (n = 32) and Fuerteventura Islands (n = 26) during July 2019. They were seeded on MacConkey (MC) agar no supplemented and supplemented (MC + CTX) with cefotaxime (2 µg/mL). Antimicrobial susceptibility was determined by disk diffusion test (CLSI, 2018). The presence of blaCTX-M, blaSHV, blaTEM,blaCMY-2 and blaOXA-1/48 genes was tested by PCR/sequencing. Furthermore, the mcr-1 (colistin resistance), tetA/tetB (tetracycline resistance), int1 (integrase of class 1 integrons) and stx1,2 genes were analyzed. Phylogenetic groups and sequence types were determined by specific-PCR/sequencing for selected isolates. Results: E. coli was obtained from all the 58 camels in MC media (100%) and in five of them in MC + CTX media (8.6%). Furthermore, 63.8% of E. coli isolates recovered from MC agar were susceptible to all the antibiotics tested. The five E. coli isolates recovered from MC + CTX media were characterized and two of them were ESBL-producers (3.4%). Both ESBL-producer isolates carried the blaCTX-M-15 gene and belonged to the lineages ST3018 (phylogroup A) and ST69 (phylogroup B1). The 3 ESBL-negative isolates recovered from MC-CTX plates were ascribed to phylogroup-B1. Conclusions: Camels can be a source of ESBL-producer bacteria, containing the widespread blaCTX-M-15 gene associated with the lineages ST3018 and ST69.

Evaluation of ESBL (Extended Spectrum Beta-Lactamase) Producing Escherichia Coli Isolated from Patients with Urinary Tract Infection by Phenotypic and Genotypic Methods

Background: Urinary Tract Infection (UTI) is the most common bacterial infection in the world. E. coli is the predominant Pathogen. This study evaluates the prevalence of ESBL in E. colis isolated from patients with urinary tract infections with phenotypic and genotypic methods.Methods: This descriptive-analytical study was done on 155 isolates of E. coli isolated from patients with urinary tract infection who had received the study consent. After accurate identification of E. coli strains. ESBL production for Escherichia coli isolates which are resistant to ceftriaxone or ceftazidime was evaluated by CDT method. TEM, SHV and CTX-M genes were identified by PCR.Results: The results showed that 30 strains from 155 strains of E. coli had ESBL. Strains of ESBL producer were more in males was lower in educated persons. 38.9% of ESBL producer had antibiotic use, 29.9% -producing Escherichia hospitalization and 31.6% uti history. The highest level of drug allergy in the ESBL was related to nitrofurantoin, and the highest resistance was related to cefazolin, co-trimoxazole. The CTX-M and the CTX-M15 gene were found in 92.7% and 57.1% of cases, respectively; also the SHV and TEM genes were not found in any of ESBL-producing Escherichia coli strains. Most therapeutic response in patients was related to cefexime, ciprofloxacin and nitrofurantoin 27.4%, 26% 21.9%, respectively.Conclusion: This study showed that the history of antibiotic use, hospitalization, uti related to increase of ESBL-producing in E. coli isolates., the CTMX-M gene is the most common gene in ESBL-producing E. coli strains.

Silver nanoparticle Bacteriostatic activity Assessment against Extended-Spectrum Beta-Lactamase Producing Uropathogenic Klebsiella pneumonia

The aims: Screen for the Extended-Spectrum Beta-Lactamase producing Klebsiella pneumonia from urinary tract infection UTI patients phenotypically and molecularly, also testing different sizes of silver nanoparticles as antibacterial for the resistance isolates. Methodology: Vitek Extended-Spectrum Beta-Lactamase test , molecular confirmed ESBL-producing isolates were checked by PCR for the presence of AmpC and blaCTX-M genes. Flat well microtiter plates were used for packing of antibacterial activity of silver nanoparticles . This study included 85 urine samples were collected from patients that admitted to the "Rizgary Hospital" in Erbil province from 15 June to 15 December 2018. Antibiotic sensitivity test of all isolates to (Ampicillin, Ampicillin/sulbactam Cefazolin, Ceftazidime Ceftriaxone, Cefepime, Imipenem, Nafcillin and Nitrofurantoin )antibiotics were tested by the disc-agar method as standardized by the National Committee for Clinical laboratory Standards (2006).Results: Out of 51 tested isolates of Klebsiella pneumonia, 11 (21.6%) were Extended-Spectrum Beta-Lactamase Producers. Their antibiotic resistance profile showed the rate of resistance isolates was (100%) to Ampicillin, Cefazolin, Ceftazidime and Ceftriaxone and ( 90%) to Cefepime .In addition the susceptibility to Imipenem was (72.7%) of isolates. The bands of the AmpC and bla CTX-M genes was noted in (42.9%) samples and the remain samples (57.1 %)were negative for both genes. The Minimum Inhibitory Concentration during incubation of Non ESBL producer - ESBL producer isolates in series concentrations of silver nanoparticles size (20 nm) was between (625 -2500) µg/ml and for size (90 nm), it was (1250) µg/ml for non ESBL producer and not affected ESBL producer isolates .The increased percentage rates of β-lactamase producing Klebsiella species were seen which was considered as an alarm, due to limitation in treatment options for UTI. It was appeared that Imipenem currently is the main available antibiotic for UTI treatment as a drug of choice. It was noticed that different sizes of silver nanoparticles showed antibacterial activity for ESBL producing isolates.

479. Associated Factors for Extended-Spectrum β-Lactamase Infection Among Patients with Solid or Hematological Malignancy

Background Cancer patients are susceptible to infections due to immunodeficiency, frequent invasive interventions-devices, chemotherapy and antibiotics exposure. Infections caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae increase morbidity and mortality. The objective was to identify clinical factors associated with ESBL in infected patients with cancer at the Instituto Nacional de Cancerología. Methods A case–control study was conducted from 2013 to 2015. Cases were infected patients with ESBL-producer Enterobacteriaceae. Controls (matched for date and ward) with non-ESBL-producer Enterobacteriaceae were included. Data were extracted from electronic medical records at index culture: clinical and admission data, Charlson index, immunosuppressive, radio and chemotherapy, neutropenia, invasive devices, surgical procedures and antimicrobial therapy. Microorganisms were identified by the automatized system. Conditional logistic regression and backward stepwise was used to identify predictors of ESBL isolation. Results A total of 265 patients with ESBL producer Enterobacteriaceae and 445 non-ESBL producers were identified, mean age 59, 61% male, 48% admitted as outpatients, 73% with solid tumors, 38% with Charlson index ≥4. E.coli and Klebsiella spp. represented 90% of microorganisms. Factor associated with ESBL producer Enterobacteriaceae were hospitalization ≥7 days (OR: 1,59; CI 1.11–2,29), hospitalization the previous year (OR: 4.02; CI 2,68–6,02), immunosuppressive therapy (OR: 2.07; CI 1,05–4.05), Β-lactam therapy the last month (OR: 1.54; CI 1.05–2.26), invasive devices (OR: 1.58; CI 1.10–2.27), active neoplasia (OR: 2,22; CI1.05–4.68), neutropenia (OR: 2.03; CI:1.26–3.27) and absence of chemotherapy during last 3 months (OR: 1.91; CI1.29–2.82). Discriminatory capacity was acceptable (AUC: 0.71). Conclusion The presence of ESBL-producer Enterobacteriaceae in oncologic patients is associated with health care, hospital admission and length of stay, invasive devices and exposure to antibiotics. The magnitude of associated factors are weak and do not completely allow the identification of cancer patients infected with ESBL-producer Enterobacteriaceae. Disclosures All authors: No reported disclosures.