Characterization of extended-spectrum beta-lactamases in Enterobacteriaceae causing nosocomial infections in a Zagreb University Hospital. - Related Documents




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99101.0000Characterization of extended-spectrum beta-lactamases in Enterobacteriaceae causing nosocomial infections in a Zagreb University Hospital. The bacteria producing extended-spectrum beta-lactamases (ESBLs) are increasingly reported. production of ESBLs by Gram-negative bacteria is the major mechanism of resistance to oxymino-cephalosporins and aztreonam. the aim of the present study was to characterize ESBLs produced by Enterobacteriaceae, collected during 2003-2005 in a University Hospital in Zagreb, and to determine the risk factors associated with nosocomial infections due to them. 76 isolates of Enterobacteriaceae were included in the study. Antibiotic susceptibility testing was performed by disk-diffusion and broth microdilution method according to CLSI. beta-lactamases were characterized by PCR and sequencing of bla(ESBL )genes. plasmids were extracted by alkaline lysis method and digested with EcoRI enzyme. Most of the strains displayed CAZ phenotype meaning a higher level of resistance to ceftazidime compared to cefotaxime and ceftriaxone. 50 strains produced SHV-ESBL, 28 tem and 8 CTX-M beta-lactamase. Sequencing of bla(SHV )genes from representative strains revealed SHV-5 beta-lactamase in 6 strains whereas sequencing of bla(CTX-M )genes identified CTX-M-3 beta-lactamase in 3 and CTX-M-15 in 5 strains. Strains were assigned to groups from A to f according to plasmid fingerprinting. The spread of SHV-5-producing strains throughout the hospital units could be due to selective pressure of ceftazidime which is widely prescribed in our hospital thus favoring survival of strains possessing a mutation at the Ambler position 240 responsible for ceftazidime and aztreonam resistance.200919567348
99010.9999Resistance phenotype-genotype correlation and molecular epidemiology of Citrobacter, Enterobacter, Proteus, Providencia, Salmonella and Serratia that carry extended-spectrum β-lactamases with or without plasmid-mediated AmpC β-lactamase genes in Thailand. Extended-spectrum β-lactamases (ESBLs) and plasmid-mediated AmpC β-lactamases (pAmpCs) have been increasingly reported among less commonly encountered genera of Enterobacteriaceae. However, little is known regarding the genetic characteristics of resistance genes and epidemiology of these genera. Lack of accurate ESBL and pAmpC detection may adversely affect therapeutic outcomes. This study investigated resistance phenotype-genotype correlation and molecular epidemiology among six genera of Enterobacteriaceae (Citrobacter, Enterobacter, Proteus, Providencia, Salmonella and Serratia) that carried ESBL with or without pAmpC genes at a university hospital in Thailand. From a total of 562 isolates, 105 isolates (18.7%) had ESBL-positive phenotype whilst 140 isolates (24.9%) harboured one or more ESBL genes. CTX-M and TEM were common ESBL-related bla genes among these isolates. The sensitivity and specificity of ESBL phenotypic detection as opposed to ESBL gene detection were 70.7% and 98.6%, respectively. pAmpC genes were detected in 96 ESBL gene-carrying isolates (68.6%) and significantly caused false negative detection of ESBL. Molecular typing based on pulsed-field gel electrophoresis revealed several clones that may be endemic in this hospital. This study indicated a high prevalence of ESBLs and pAmpCs among less common members of the family Enterobacteriaceae in Thailand and these resistant bacteria need to be monitored.201120880563
99220.9999Phenotypic and genotypic evaluation of beta-lactamases (ESBL and KPC) among enterobacteria isolated from community-acquired monomicrobial urinary tract infections. Beta-lactamases enzymes such as extended-spectrum beta-lactamases (ESBL) and carbapenemase type beta-lactamases (KPC) confer resistance to beta-lactam drugs among Gram-negative rods, mainly Enterobacteriaceae, as those frequently related to urinary tract infections (UTI). The aim of this study was to evaluate ESBL and KPC among enterobacteria isolated from monomicrobial UTI and to establish correlations between the presence of genetic markers and the phenotypic resistance to beta-lactam antibiotics. Out of 12 304 urine samples collected during 2009, 93 enterobacteria showing an ESBL phenotype were recovered. Imipenem was used for KPC screening and modified disk approximation assay was used for detection of ESBL phenotype. Polymerase chain reaction was used for screening of bla(SHV), bla(TEM), bla(CTX-M), and bla(KPC). Considering the isolated bacteria showing ESBL phenotype 56% of the isolates were positive for two genes. The bla(TEM) was the most frequent (87·1%). Neither KPC phenotype nor bla(KPC)-harboring bacteria were observed. Monitoring the antimicrobial resistance is extremely important to sustain empirical therapy of community-acquired urinary tract infections (Co-UTI).201424621159
98930.9999Development of a Method for the Fast Detection of Extended-Spectrum β-Lactamase- and Plasmid-Mediated AmpC β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae from Dogs and Cats in the USA. Antibiotic resistance, such as resistance to beta-lactams and the development of resistance mechanisms, is associated with multifactorial phenomena and not only with the use of third-generation cephalosporins. Many methods have been recommended for the detection of ESBL and pAmpC β-lactamase production but they are very subjective and the appropriate facilities are not available in most laboratories, especially not in clinics. Therefore, for fast clinical antimicrobial selection, we need to rapidly detect ESBL- and pAmpC β-lactamase-producing bacteria using a simple method with samples containing large amounts of bacteria. For the detection of ESBL- and pAmpC phenotypes and genes, the disk diffusion test, DDST and multiplex PCR were conducted. Of the 109 samples, 99 (90.8%) samples were grown in MacConkey broth containing cephalothin, and 71 samples were grown on MacConkey agar containing ceftiofur. Of the 71 samples grown on MacConkey agar containing ceftiofur, 58 Escherichia coli and 19 Klebsiella pneumoniae isolates, in particular, harbored β-lactamase genes. Of the 38 samples that did not grow in MacConkey broth containing cephalothin or on MacConkey agar containing ceftiofur, 32 isolates were identified as E. coli, and 10 isolates were identified as K. pneumoniae; β-lactamase genes were not detected in these E. coli and K. pneumoniae isolates. Of the 78 ESBL- and pAmpC β-lactamase-producing E. coli and K. pneumoniae, 55 (70.5%) isolates carried one or more ESBL genes and 56 (71.8%) isolates carried one or more pAmpC β-lactamase genes. Our method is a fast, and low-cost tool for the screening of frequently encountered ESBL- and pAmpC β-lactamase-producing bacteria and it would assist in diagnosis and improve therapeutic treatment in animal hospitals.202336830436
105340.9999Antimicrobial Resistance and Extended-Spectrum Beta-Lactamase Genes in Enterobacterales, Pseudomonas and Acinetobacter Isolates from the Uterus of Healthy Mares. Antibiotic-resistant bacteria are a growing concern for human and animal health. The objective of this study was to determine the antimicrobial resistance and extended-spectrum beta-lactamase genes in Enterobacterales, Pseudomonas spp. and Acinetobacter spp. isolates from the uterus of healthy mares. For this purpose, 21 mares were swabbed for samples, which were later seeded on blood agar and MacConkey agar. The isolates were identified using MALDI-TOF and the antimicrobial susceptibility test was performed using the Kirby-Bauer technique. To characterize the resistance genes, a polymerase chain reaction (PCR) scheme was performed. Of the isolates identified as Gram-negative, 68.8% were Enterobacterales, represented by E. coli, Enterobacter cloacae, Citrobacter spp., and Klebsiella pneumoniae; 28.1% belonged to the genus Acinetobacter spp.; and 3.1% to Pseudomonas aeruginosa. A 9.3% of the isolates were multidrug-resistant (MDR), presenting resistance to antibiotics from three different classes, while 18.8% presented resistance to two or more classes of different antibiotics. The diversity of three genes that code for ESBL (bla(TEM), bla(CTX-M) and bla(SHV)) was detected in 12.5% of the strains. The most frequent was bla(SHV), while bla(TEM) and bla(CTX-M) were present in Citrobacter spp. and Klebsiella pneumoniae. These results are an alarm call for veterinarians and their environment and suggest taking measures to prevent the spread of these microorganisms.202337764953
99750.9999Prevalence and antibacterial resistance patterns of extended-spectrum beta-lactamase producing Gram-negative bacteria isolated from ocular infections. PURPOSE: Extended-spectrum beta-lactamases (ESBLs) mediated resistance is more prevalent worldwide, especially among Gram-negative bacterial isolates, conferring resistance to the expanded spectrum cephalosporins. As limited data were available on the prevalence of ESBLs in this area, the current study was undertaken to determine the prevalence, antibacterial resistance patterns, and molecular detection and characterization of ESBL encoding resistance genes among ocular Gram-negative bacterial isolates from ocular infections. MATERIALS AND METHODS: A prospective study was done on 252 ocular Gram-negative bacterial isolates recovered from ocular infections during a study period from February 2011 to January 2014. All isolates were subjected to detection of ESBLs by cephalosporin/clavulanate combination disc test and their antibacterial resistance pattern was studied. Molecular detection and characterization of ESBL encoding blaTEM -, blaSHV , blaOXA -, and blaCTX-M (phylogenetic groups 1, 2, 9, and 8/25) resistance genes by multiplex polymerase chain reaction and DNA sequence analysis. RESULTS: Of all Gram-negative bacteria, Pseudomonas aeruginosa (44%) was the most common strain, followed by Enterobacter agglomerans and Klebsiella pneumoniae each (10%). Among the 252, 42 (17%) were ESBL producers. The major source of ESBL producers were corneal scraping specimens, highest ESBL production was observed in P. aeruginosa 16 (38%) and Escherichia coli 7 (16.6%). Among ESBL-producing genes, the prevalence of blaTEM -gene was the highest (83%) followed by blaOXA -gene (35%), blaSHV -gene (18.5%), and blaCTX-M-1 -gene (18.5%) alone or together. CONCLUSION: The higher rate of prevalence of ESBLs-encoding genes among ocular Gram-negative bacteria is of great concern, as it causes limitation to therapeutic options. This regional knowledge will help in guiding appropriate antibiotic use which is highly warranted.201627221683
101660.9999Investigation of CTX-M Type Extended-Spectrum β-Lactamase, Carbapenem and Colistin Resistance in Enterobacterales Isolated From Dairy Cattle in Turkey. BACKGROUND: The increasing prevalence of antimicrobial resistance in animals, particularly the spread of multidrug-resistant Enterobacterales, poses a significant zoonotic and public health risk. OBJECTIVE: The aim of this study was to investigate extended-spectrum β-lactamase (ESBL), carbapenem and colistin resistance among Enterobacterales in faecal swabs of dairy cattle. METHODS: A total of 400 samples were cultured on Mac Conkey screening media for ESBL, carbapenem and colistin resistance. The grown Enterobacterales were identified by MALDI-TOF-MS, followed by ceftriaxone, cefotaxime and ceftazidime resistance and double disk synergy. ESBL resistance genes were identified by polymerase chain reaction (PCR) and Sanger sequencing. Bacteria grown on colistin screening media were investigated for colistin resistance by EUCAST microbroth dilution method. RESULTS: A total of 89 (22.25%) of the bacteria grown from 400 samples were identified as potential ESBL-producing Enterobacterales members. A number of 53 (59.5%) of them were identified as ESBL blaCTX-M as a result of PCR, and 10 of them were identified as blaCTX-M-15/28/36/66 as a result of sequencing. None of the samples cultured on carbapenem medium grew. A total of 18 samples grown in colistin medium were found to be colistin sensitive by broth microdilution. Genotypes were not included in the study. All isolated bacteria were identified as Escherichia coli. SOLUTION: In this study, blaCTX-M-15 and its derivatives, which are common in humans, were also found to be the predominant ESBL type in animals. Monitoring resistance in animals together with resistance in human infections may provide more important data on the spread of resistance.202540704983
98770.9999Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-Producing Escherichia coli among Uropathogens of Pediatrics in North of Iran. Escherichia coli remains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs) making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producing E. coli isolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of the E. coli isolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR) for the presence or absence of CTX, TEM, SHV, GES, and VEB beta-lactamase genes. About 30.5% of isolated E. coli was ESBL-producing strain. The TEM gene was the most prevalent (49%) followed by SHV (44%), CTX (28%), VEB (8%), and GES (0%) genes. The ESBL-producing E. coli isolates were susceptible to carbapenems (66%) and amikacin (58%) and showed high resistance to cefixime (99%), colistin (82%), and ciprofloxacin (76%). In conclusion, carbapenems were the most effective antibiotics against ESBl-producing E. coli in urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise.201526064896
99580.9999Genetic Characterization of Extended-Spectrum Beta-Lactamase (ESBL) and Metallo-Beta-Lactamase (MBL) Producing Klebsiella pneumoniae from Diabetic Foot Ulcer (DFU). BACKGROUND: Antibiotic resistance in common pathogenic bacteria is linked with the genetic makeup. The genetic basis of antibiotic resistance may vary in different species or pathophysiological conditions. OBJECTIVES: We studied the antibiotic resistance in Klebsiella pneumonia isolates from DFU in the western Indian population. We also studied the presence of ESBL and MBL mechanisms of antibiotic resistance along with the prevalence of the genes involved in ESBL (TEM (ESBL) , SHV (ESBL) , and CTX-M (ESBL) ) and MBL (NDM-1 (bla) , KPC (bla) , OXA-48 (bla) , and VIM (bla) ) production. RESULTS: A total of 161 K. pneumoniae isolates were analyzed; among which 50.93% were positive for ESBL and 45.96% were positive for MBL production. Most of the isolates were resistant to antibiotics used in the present study and partially resistant to Imipenem and Amikacin. There was no relation between the antibiotic resistance of the isolates and the production of ESBL or MBL mechanism of antibiotic resistance. Further, TEM (ESBL) was the most prevalent gene in K. pneumoniae isolates followed by CTX-M (ESBL) , NDM-1 (bla) , SHV (ESBL) , and KPC (bla) . VIM (bla) was the least prevalent gene found in K. pneumoniae isolates. There was no difference in the prevalence of the genes with respect to the presence or absence of ESBL and MBL mechanism of resistance. Further, there was no relation between the prevalence of the genes and antibiotic resistance in K. pneumoniae isolates. CONCLUSION: These results along with the literature review suggest that the prevalence of the genes involved in antibiotic resistance mechanisms are widespread in India and their distribution varies in different studies.202439346272
99890.9999Extended spectrum beta-lactamases among Gram-negative bacteria of nosocomial origin from an intensive care unit of a tertiary health facility in Tanzania. BACKGROUND: Resistance to third generation cephalosporins due to acquisition and expression of extended spectrum beta-lactamase (ESBL) enzymes among Gram-negative bacteria is on the increase. Presence of ESBL producing organisms has been reported to significantly affect the course and outcome of an infection. Therefore infections due to ESBL isolates continue to pose a challenge to infection management worldwide. The aim of this study was to determine the existence and to describe phenotypic and genotypic characteristics of ESBLs in an Intensive Care Unit (ICU) setting in Tanzania. METHODS: Between October 2002 and April 2003, clinical information and samples were collected from patients suspected to have nosocomial infections in an Intensive Care Unit of a tertiary hospital in Tanzania. The isolates were identified, tested for antimicrobial susceptibility and analysed for presence of ESBL genes. RESULTS: Thirty-nine Gram-negative bacteria were isolated from clinical samples of 39 patients. These isolates included 13 Escherichia coli, 12 Enterobacter spp, 5 Pseudomonas spp, 4 Proteus spp, 2 Klebsiella. pneumoniae, 2 Citrobacter freundii and 1 Chryseomonas luteola. Eleven (28.2%) of these isolates were ESBL producing. The ESBL genes characterised were SHV-12, SHV-28 and CTX-M-15. The ESBL producing isolates were more resistant to gentamicin and ciprofloxacin than non-ESBL producing isolates. CONCLUSION: This study shows the presence of ESBL genes among Gram-negative bacteria in the ICU setting in Tanzania. There is a need to institute strict hospital infection control policy and a regular surveillance of resistance to antimicrobial agents.200516225701
955100.9999Occurrence and characteristics of extended-spectrum β-lactamase- and carbapenemase- producing bacteria from hospital effluents in Singapore. One of the most important resistance mechanisms in Gram-negative bacteria today is the production of enzymes causing resistance to cephalosporin and carbapenem antibiotics. The spread of extended-spectrum β-lactamases (ESBL)- and carbapenemase- producing Gram-negative bacteria is an emerging global public health problem. The aim of the present study was to (i) assess the prevalence of carbapenem-resistant bacteria (CRB) and ESBL-producing strains in sewage effluents from two major hospitals in Singapore, (ii) characterize the isolated strains and (iii) identify some of the ESBL and carbapenemase genes responsible for the resistance. CHROMagar ESBL and KPC plates were used to rapidly screen for ESBL-producing bacteria and those expressing reduced susceptibility to carbapenems, respectively. The abundance of ESBL-producers and CRB in hospital wastewater ranged between 10(3) and 10(6)CFU/mL. Out of the 66 isolates picked from ESBL and KPC plates, 95%, 82%, 82% and 76% were resistant to ceftriaxone, ceftazidime (3rd generation cephalosporin family), ertapenem and meropenem (carbapenem family), respectively. Among the resistant isolates, the most predominant taxa identified were Pseudomonas spp. (28.2%), Klebsiella spp. (28.2%), Enterobacter spp. (18.3%) and Citrobacter spp. (11.3%). PCR and sequencing analysis showed that the predominant β-lactamase genes were bla(SHV) (41.1%) followed by bla(NDM-1) (35.6%), bla(CTX) (35.6%) and bla(KPC) (28.8%). The results of this study show a high prevalence of bacteria resistant to modern extended-spectrum cephalosporins and carbapenems and the presence of ESBL- and carbapenemase producers in hospital effluents. These findings support the need to improve management of hospital wastewater in order to minimize the spread of antimicrobial resistant microorganisms from this source.201829751417
994110.9999Moroccan Hospital Cockroaches: Carriers of Multidrug-Resistant Gram-Negative Bacteria. Antimicrobial resistance in Gram-negative bacteria (GNB) is a growing global health concern, particularly in hospital environments, where cockroaches act as vectors for resistant strains. This study aimed to analyze antimicrobial resistance and biofilm formation in GNB isolated from cockroaches collected in the hospital environment. Cockroaches were collected, and bacterial isolation was performed from their gut contents and external surfaces. GNB strains were tested for antibiotic susceptibility using the disk diffusion method and examined for Extended-spectrum β-lactamases (ESBLs) and carbapenemases production. Molecular characterization of ESBLs and carbapenemases in GNB involved PCR amplification of antibiotic resistance genes, while biofilm formation was studied using a microplate assay. Seventy-five cockroaches were collected from which 165 GNB were isolated. The prevalence of ESBL-producing and carbapenemase-producing GNB was 6.7 and 1.8%, respectively. The predominant ESBL gene was bla(CTX-M-28), while bla(NDM-1) was the only carbapenemase gene detected. The qnrS1 gene was found in one NDM-1-producing Klebsiella pneumoniae and three ESBL-producing Escherichia coli. The qacΔE1 gene was detected in an NDM-1-producing Citrobacter freundii and a CTX-M-28-producing E. coli, whereas one NDM-1-producing Enterobacter cloacae carried both qacΔE1 and acrA genes. Strains harboring qacΔE1 and/or acrA genes exhibited biofilm-forming capabilities, with biofilm formation observed in 81.81% of ESBL-producing isolates and 100% of carbapenemase-producing isolates. The study underscores the role of cockroaches in carrying and disseminating ESBL- and carbapenemase-producing GNB in hospital settings. The coexistence of disinfectant resistance genes and antibiotic resistance suggests co-selection mechanisms, while biofilm formation enhances bacterial survival. These findings underline the urgent need for infection control strategies.202540095169
1503120.9998OXA-48 Carbapenemase-Encoding Transferable Plasmids of Klebsiella pneumoniae Recovered from Egyptian Patients Suffering from Complicated Urinary Tract Infections. Gram-negative bacteria are common causes of urinary tract infections (UTIs). Such pathogens can acquire genes encoding multiple mechanisms of antimicrobial resistance, including carbapenem resistance. The aim of this study was to detect the carbapenemase-producing ability of some Gram-negative bacterial isolates from urine specimens of patients suffering from complicated UTIs at two vital tertiary care hospitals in Cairo, Egypt; to determine the prevalence of carbapenemase genes among plasmid-bearing isolates; and explore the possibility of horizontal gene transfer to other bacterial species. The collected isolates were subjected to antimicrobial susceptibility testing, phenotypic analysis of carbapenemase production, and molecular detection of plasmid-borne carbapenemase genes, then the extracted plasmids were transformed into competent E. coli DH5α. A total of 256 Gram-negative bacterial clinical isolates were collected, 65 (25.4%) isolates showed carbapenem resistance of which 36 (55.4%) were carbapenemase-producers, and of these 31 (47.7%) harbored plasmids. The extracted plasmids were used as templates for PCR amplification of bla(KPC), bla(NDM), bla(VIM), bla(OXA-48,) and bla(IMP) carbapenemase genes. The bla(OXA-48) gene was detected in 24 (77.4%) of the tested isolates while bla(VIM) gene was detected in 8 (25.8%), both bla(KPC) and bla(NDM) genes were co-present in 1 (3.2%) isolate. Plasmids carrying the bla(OXA-48) gene from 4 K. pneumoniae clinical isolates were successfully transformed into competent E. coli DH5α. The transformants were carbapenemase-producers and acquired resistance to some of the tested antimicrobial agents as compared to untransformed E. coli DH5α. The study concluded that the rate of carbapenem resistance among Gram-negative bacterial uropathogens in Cairo, Egypt is relatively high and can be transferred horizontally to other bacterial host(s).202134571766
1045130.9998ESBL-Producing Enterobacter cloacae Complex and Klebsiella pneumoniae Harbouring bla(CTX-M-15) and bla(CTX-M-55) Potentially Risk the Worldwide Spread of ESBL-Producing Bacteria Through Contaminated Dried Fishery Products. The transmission of life-threatening bacteria with plasmid-mediated antibiotic resistance poses a significant challenge to public health. This study aimed to determine the presence of plasmid-mediated antibiotic resistance genes in Enterobacterales isolates obtained from dried fishery products. Eighty-one dried fishery products were purchased from Vietnamese markets. Enterobacterales were isolated using a CHROMagar Escherichia coli coliform agar containing cefotaxime or meropenem. The isolated strains were assessed for their susceptibility to 14 antibiotics using a disc diffusion assay. Extended-spectrum β-lactamase (ESBL) sub-group typing was performed based on multiplex PCR of isolated ESBL-producing strains. In addition, Enterobacter cloacae AD2-1, which showed multiple drug resistance, was subject to whole-genome sequence analysis. CTX-resistant bacteria were isolated from 22% and MEM-resistant bacteria from 27% of the Vietnamese samples. CTX-resistant bacteria were isolated from 17% and MEM-resistant bacteria from 4% of Japanese samples. Bacterial identification indicated that 98 strains were isolated, of which 29 strains of E. coli, 28 of Enterobacter cloacae complex, 19 of Staphylococcus spp., and 9 of Klebsiella pneumoniae were predominant in Vietnamese samples. Japanese samples were predominantly contaminated with E. cloacae complex. Multiplex PCR and sequencing was used to determine the presence of ESBL-related genes bla(CTX-M-15) and bla(CTX-M-55) in E. cloacae and K. pneumoniae isolates. E. cloacae AD2-1 isolated from the Vietnamese dried fish was resistant to 14 antibiotics, and approximately 300 kbp of the IncHI2 plasmid harboured multiple antibiotic resistance genes and formed an antibiotic resistance gene region. This E. cloacae is considered a risk for the spread of antibiotic resistance across countries.202541171320
1038140.9998Isolation of Extended Spectrum β-lactamase (ESBL) Producing Bacteria from Urban Surface Waters in Malaysia. BACKGROUND: This was a preliminary study to test for the presence of multiple antibiotic-resistant extended spectrum β-lactamase (ESBL) producing bacteria in Malaysian urban surface waters. Although the literature review revealed several published papers on clinical ESBL isolates in Malaysia, none were found on ESBL isolates obtained from local surface waters. METHODS: Isolated bacterial species were tested for resistance to cefotaxime, amoxicillin/clavulanate and aztreonam, and susceptibility to imipenem and meropenem using antibiotic susceptibility testing (AST) by disc diffusion. This served as a screening step to detect bacteria that could be potential ESBL species. 16S ribose ribonucleic acid (rRNA) polymerase chain reaction (PCR) testing with two clusters of bla (β-lactamase) gene primers was used to test for the bla genes CTX-M (Groups 1, 2, 9), OXA-1, SHV and TEM. RESULTS: A total of 19 isolates were found, possessing at least one of the bla genes tested for. There was a relatively high occurrence of CTX-M genes (84.2%) among these, followed by TEM genes (47.4%). The isolates were identified as Enterobacteriaceae (89.5%), predominantly Escherichia coli and Klebsiella pneumoniae. CONCLUSION: There appears to be a high occurrence of ESBL-bacteria in local surface waters, among these being opportunistic pathogens. The persistence and spread of these species in the environment poses a threat to exposed human populations.201323966820
1054150.9998Molecular detection of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates of chicken origin from East Java, Indonesia. BACKGROUND AND AIM: Klebsiella pneumoniae is one of the respiratory disease agents in human and chicken. This bacterium is treated by antibiotic, but this treatment may trigger antibiotic resistance. Resistance gene in K. pneumoniae may be transferred to other bacteria. One of the known resistance genes is extended-spectrum β-lactamase (ESBL). This research aimed to study K. pneumoniae isolated from chicken farms in East Java, Indonesia, by observing the antibiotic resistance pattern and detect the presence of ESBL coding gene within the isolates. MATERIALS AND METHODS: A total of 11 K. pneumoniae isolates were collected from 141 chicken cloacal swabs from two regencies in East Java. All isolates were identified using the polymerase chain reaction method. Antimicrobial susceptibility was determined by agar dilution method on identified isolates, which then processed for molecular characterization to detect ESBL coding gene within the K. pneumoniae isolates found. RESULTS: The result of antibiotic sensitivity test in 11 isolates showed highest antibiotic resistance level toward ampicillin, amoxicillin, and oxytetracycline (100%, 100%, and 90.9%) and still sensitive to gentamicin. Resistance against colistin, doxycycline, ciprofloxacin, and enrofloxacin is varied by 90.9%, 54.5%, 27.3%, and 18.2%, respectively. All isolates of K. pneumoniae were classified as multidrug resistance (MDR) bacteria. Resistance gene analysis revealed the isolates harbored as bla (SHV) (9.1%), bla (TEM) (100%), and bla (CTX-M) (90.9%). CONCLUSION: All the bacterial isolates were classified as MDR bacteria and harbored two of the transmissible ESBL genes. The presence of antibiotic resistance genes in bacteria has the potential to spread its resistance properties.201931190714
984160.9998Genetic characterization of TEM-type ESBL-associated antibacterial resistance in Enterobacteriaceae in a tertiary hospital in Ghana. BACKGROUND: Antibiotic resistance due to the presence of extended-spectrum beta-lactamases (ESBLs) among Enterobacteriaceae is a worldwide problem. Data from Ghana regarding this resistance mechanism is limited. This study was designed to investigate the presence of TEM-type ESBL genes, their locations and their conjugabilities in clinical isolates of enterobacteria collected from the Korle-Bu Teaching Hospital in Ghana. METHODS: Study isolates were characterized with respect to ESBL phenotype, TEM-type ESBL gene detection, location of the ESBL gene(s) and conjugability of the ESBL phenotype using nalidixic acid-resistant Escherichia coli K-12 as recipient. Phenotyping was by Kirby Bauer disk diffusion using cefpodoxime, ceftazidime, cefotaxime and their combinations with clavulanate. Gene detections were by PCR using blaTEM primers. RESULTS: Overall, 37.96 % of 137 clinical isolates showed ESBL phenotype. The ESBLs occurred mostly in Klebsiella spp. (42.3 %) and then Escherichia coli (34.6 %). The TEM gene was detected in 48.1 % of ESBL-positive isolates and was determined to be plasmid-borne in 24 of 25 blaTEM detections. Overall, 62.7 % of TEM-producing isolates transferred the ESBL phenotype by conjugation. CONCLUSIONS: The results highlight the presence of TEM-type ESBLs in the Korle-Bu Teaching Hospital and show considerable risk of environmental contamination through the urine of infected persons. An inhibition zone chart was generated which indicates the possible presence of complex beta-lactamase types. The data points to the fact that the ESBL-producing bacteria may disseminate this resistance mechanism via conjugation.201627145868
2150170.9998Analysis of drug resistance genes of integrons in clinical isolates of Escherichia coli from elderly bloodstream infections. This experiment was carried out to provide a basis for the treatment of clinical bloodstream infections by analyzing the drug resistance characteristics and integrated gene distribution of Escherichia coli in bloodstream infections in elderly patients. For this aim, E. coli were collected for bacterial identification and drug sensitivity testing from bloodstream infections in elderly patients in the hospital from January 2016 to December 2019. ESBLs positive strains were assayed for genotypes and their integron carriage rates by PCR amplification. The characteristics and differences of various genotype rates were compared and analyzed. Results showed that a total of 230 E. coli strains were isolated. The detection rate of ESBLs-producing bacteria was 37.39 %. ESBLs-producing E. coli showed a high rate of resistance to cefepime, levofloxacin, cotrimoxazole, and ticarcillin/clavulanic acid (>40%). The resistance rate of 230 strains of E. coli to meropenem, minocycline, amikacin, gentamicin and cefoxitin was less than 20%. Among the ESBLs-producing E. coli in bloodstream infections in elderly patients, CTX-M-9 accounted for 27.91%, CTX-M-2 for 17.44%, and SHV for 13.95%. The detection rate of type I integrated genes was 41.30%, and type II and III integrated genes were not detected. ESBLs-producing genotyping-positive bacteria were detected with more than 50% of type I integrated genes. It was concluded that type I integrated genes in ESBLs-producing E. coli isolated from elderly patients carried resistance genes such as CTX-M-9 and CTX-M-2 aggravating multi-drug resistance in bacteria.202236227675
1098180.9998Extended spectrum beta-lactamase and fluoroquinolone resistance genes among Escherichia coli and Salmonella isolates from children with diarrhea, Burkina Faso. BACKGROUND: The emergence and spread of multidrug-resistant gram-negative bacteria (MDR) has become a major public health concern worldwide. This resistance is caused by enzymes-mediated genes (i.e., extended spectrum beta-lactamases) that are common in certain Enterobacterioceae species. However, the distribution of these genes is poorly documented in Burkina Faso. This study aims to determine the prevalence and distribution of the resistant genes coding for broad spectrum beta-lactamases and quinolones in rural Burkina Faso. METHODS: Multiplex PCR assays were carried out to detect ESBL-encoding genes, including bla(OXA), bla(TEM), bla(CTX-M), bla(SHV). The assays also assessed the presence of quinolone resistance gene namely qnrA, qnrB and qnrS in the quinolone-resistance DEC and Salmonella strains. RESULTS: The Extended-Spectrum Beta-Lactamases (ESBL) resistance phenotype was reported in all the E. coli isolates (5/5). Cross-resistance phenotype to quinolones (CRQ) was shown by one Salmonella strain (1/9) and three E. coli (3/5). Cross-resistance phenotypes to fluoroquinolones (CRFQ) were harboured by one Salmonella (1/9) and carbapenemase phenotypes were detected in two E. coli strains (2/5). Whilst the bla(OXA) genes were detected in 100% (5/5) of E. coli isolates and in 33.33% (3/9) Salmonella isolates. One strain of E. coli (1/5) harbored the bla(CTX-M) gene and the qnrB gene simultaneously. CONCLUSIONS: This study identified β-lactam (bla) and quinolone resistance (qnr) genes in multidrug-resistant E. coli and Salmonella spp. in rural Burkina Faso. Our finding which highlighted the enterobacteriaceae strains resistance to β-lactams and quinolones are of high interest for adequate management of antimicrobial resistant genes outbreak in Burkina Faso.202033010801
913190.9998Intestinal carriage of colistin-resistant Enterobacteriaceae at Saint Georges Hospital in Lebanon. OBJECTIVES: The increase in resistance to antibiotics has led to the revival of colistin as the last option for treatment, which automatically led to an increase of colistin-resistant, Gram-negative bacteria. In this study, we report the presence of clinical colistin-resistant Enterobacteriaceae isolated from a Lebanese hospital. METHODS: From 23 rectal swabs, eight colistin-resistant clinical strains (five Escherichia coli, two Enterobacter cloacae, and one Klebsiella pneumoniae) were isolated. Antibiotic susceptibility testing was performed using the disk diffusion method and Etest. The broth microdilution method was used to determine colistin susceptibility. Reverse transcription polymerase chain reaction (RT-PCR), standard PCR and sequencing were used to investigate genes encoding for extended-spectrum β-lactamases, carbapenemases and colistin resistance. Genotyping of these isolates was conducted by multilocus sequence typing (MLST). RESULTS: Results of antibiotic susceptibility testing revealed that all isolates were resistant to colistin. They had MICs for colistin that ranged from 8 to 32 mg/L. Real-time PCR results showed that five strains harboured bla(TEM-1) and one strain harboured bla(TEM-163). Moreover, four strains were positive for bla(CTX-M-15), bla(CTX-M-103) and bla(CTX-M-189), and K. pneumoniae harboured bla(SHV-1). Observed colistin resistance was linked to amino acid substitutions into protein sequences of pmrA/B, phoP/Q, and mgrB. Interestingly, we report here a mutation in the mgrB regulator and pmrA/B, phoP/Q in colistin-resistant E. cloacae and E. coli clinical isolates for the first time in Lebanon. CONCLUSION: This study highlights the presence of colistin-resistant Gram-negative bacteria in a Lebanese hospital, which is worrisome. An urgent strategy needs to be adopted to avoid the spread of such bacteria.202031838239