Molecular characterization of carbapenem-resistant Klebsiella pneumoniae in a tertiary university hospital in Turkey. - Related Documents




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212701.0000Molecular characterization of carbapenem-resistant Klebsiella pneumoniae in a tertiary university hospital in Turkey. The aim of this study was to identify the resistance genes and genetic relationship of carbapenemase-resistant Klebsiella pneumoniae (CRKP) identified in a tertiary university hospital in Turkey. During the study, CRKP was isolated from 137 patients. Resistance genes were studied in 94 isolates. Among these isolates, most of the CRKP produced only oxacillinase (OXA)-48 (91.5%); however, 4.3% of the isolates produced only New Delhi metallo-beta-lactamase 1 (NDM-1), 1% produced both OXA-48 and NDM-1, and 3.2% produced imipenem. This study adds Turkey to the growing list of countries with NDM-1-producing bacteria and shows that NDM-1 may easily spread worldwide.201323623803
212610.9999Carbapenemase genes among multidrug resistant gram negative clinical isolates from a tertiary hospital in Mwanza, Tanzania. The burden of antimicrobial resistance (AMR) is rapidly growing across antibiotic classes, with increased detection of isolates resistant to carbapenems. Data on the prevalence of carbapenem resistance in developing countries is limited; therefore, in this study, we determined the prevalence of carbapenemase genes among multidrug resistant gram negative bacteria (MDR-GNB) isolated from clinical specimens in a tertiary hospital in Mwanza, Tanzania. A total of 227 MDR-GNB isolates were analyzed for carbapenem resistance genes. For each isolate, five different PCR assays were performed, allowing for the detection of the major carbapenemase genes, including those encoding the VIM-, IMP-, and NDM-type metallo-beta-lactamases, the class A KPC-type carbapenemases, and the class D OXA-48 enzyme. Of 227 isolates, 80 (35%) were positive for one or more carbapenemase gene. IMP-types were the most predominant gene followed by VIM, in 49 (21.59%) and 28 (12%) isolates, respectively. Carbapenemase genes were most detected in K. pneumoniae 24 (11%), followed by P. aeruginosa 23 (10%), and E. coli with 19 isolates (8%). We have demonstrated for the first time a high prevalence of MDR-GNB clinical isolates having carbapenem resistance genes in Tanzania. We recommend routine testing for carbapenem resistance among the MDR-GNB particularly in systemic infections.201424707481
212120.9999Investigation of VIM, IMP, NDM-1, KPC AND OXA-48 enzymes in Enterobacteriaceae strains. Gram-negative bacteria especially Enterobacteriaceae species have become an increasing etiologic agent of nosocomial infections. The development of resistance to carbapenems have become an increasing problem in the treatment of nosocomial infections. Especially carbapenamases are common for Enterobacteriaceae strains. This study was performed to detect the types of carbapenemases in Enterobacteriaceae strains isolated from various clinical samples. Enterobacteriaceae species were isolated from urine, blood, tracheal aspirates, wound, and other respiratory samples. Susceptibility of isolates to imipenem, meropenem and ertapenem was tested. Carbapenemase genes were studied using HyplexSuperBug ID kit. VIM (1-13), IMP (1-22), NDM-1, KPC(1-10) and OXA-48 genes were investigated. Ninety-five isolates of Enterobacteriaceae spp. were included in the study. Sixty isolates were resistant to imipenem, meropenem and ertapenem and 20 isolates were found resistant to imipenem or ertapenem while 15 were susceptible to all carbapenems. Among the isolates with carbapenem resistance, 57 were positive for one carbapenemase gene and susceptible isolates did not have carbapenemase gene. OXA-48 was found in 49 of the isolates (86%), NDM-1 in 6 (10.5%) isolates, VIM in 2 isolates. IMP and KPC gene loci were not identified. Carbapenemase genes play a crucial role in the development and spread of resistant strains.201526051720
212030.9999Antimicrobial Resistance Patterns of Gram-negative Bacteria in an Iranian Referral Pediatric Hospital: A Present Danger of New Delhi Metallo-β- lactamase. BACKGROUND: Antimicrobial resistance among gram-negative bacteria has been growing, particularly in developing countries, like Iran. The emergence and spread of carbapenem-resistance mechanisms is a major public health concern because no definite treatments have yet been established for this problem. This study aimed to evaluate antibiotic susceptibility of gram-negative bacteria, metallo-β-lactamases (MBLs) and carbapenemase-producing genes, including bla (NDM), bla (VIM), and bla (IMP) in patients referred to Children's Medical Center, Tehran, Iran. MATERIAL AND METHODS: In this cross-sectional study, a total of 944 gram-negative isolates were tested in the study, and antimicrobial susceptibility testing was performed. Moreover, MBL production of carbapenem-resistant isolates, as well as the presence of bla (NDM), bla (VIM), and bla (IMP), was investigated. RESULTS: The most common gram-negative isolated bacteria were Escherichia coli (489 samples, 52%), followed by Klebsiella pneumoniae (167 samples, 18%), Pseudomonas aeruginosa (101 samples, 11%), Enterobacter spp. (64 samples, 7%), Pseudomonas spp. (35 samples, 4%), Acinetobacter baumannii (18 samples, 2%), and Burkholderia cepacia (17 samples, 2%). Imipenemresistant was found in 75%, 61%, and 60% of Stenotrophomonas maltophilia, Enterobacter spp., and A. baumannii isolates, respectively. Moreover, the highest resistance to meropenem was observed in S. maltophilia, A. baumannii, P. aeruginosa, and B. cepacia (100%, 96%, 83%, and 61.5%, respectively). Double disk synergy test (DDST) results showed that 112 out of 255 carbapenem- resistant isolates (44%) were MBL-producing ones. The presence of the bla (NDM) gene was identified in 32 (29%) of MBL-producing isolates, 13 of which were K. pneumoniae, 7 P. aeruginosa, and 7 E. coli, 3 Enterobacter spp., and 2 Klebsiella spp., respectively. The presence of the bla (IMP) and bla (VIM) genes was detected in 2 (2%) and 1 (1%) of MBL-producing isolates. These genes were detected in only MBL-producing P. aeruginosa isolates. CONCLUSION: Our findings suggest the emergence of NDM-producing strains in our hospital, and bla NDM was the most frequently detected carbapenemase gene in MBL-producing P. aeruginosa, K. pneumoniae, and Klebsiella spp. Since such bacteria can easily spread among patients in the hospital, a strong infection control and prevention plan is highly recommended.202337106518
212540.9999Emergence of Carbapenem-Resistant Gram-Negative Isolates in Hospital Settings in Djibouti. Introduction: The antimicrobial resistance (AMR) of bacteria is increasing rapidly against all classes of antibiotics, with the increasing detection of carbapenem-resistant isolates. However, while growing prevalence has been reported around the world, data on the prevalence of carbapenem resistance in developing countries are fairly limited. In this study, we investigated and determined the resistance rate to carbapenems among multidrug-resistant Gram-negative bacteria (MDR-GNB) isolated in Djibouti and characterized their resistance mechanisms. Results: Of the 256 isolates, 235 (91.8%) were identified as Gram-negative bacteria (GNB). Of these GNBs, 225 (95.7%) isolates exhibited a multidrug resistance phenotype, and 20 (8.5%) isolates were resistant to carbapenems, including 13 Escherichia coli, 4 Acinetobacter baumannii, 2 Klebsiella pneumoniae and 1 Proteus mirabilis. The most predominant GNB in this hospital setting were E. coli and K. pneumoniae species. Carbapenemase genes such as bla(OXA-48) and bla(NDM-5) were identified, respectively, in six and four E. coli isolates, whereas the carbapenemase bla(NDM-1) was identified in three E. coli, two K. pneumoniae, one P. mirabilis and one A. baumannii. Moreover, three A. baumannii isolates co-hosted bla(OXA-23) and bla(NDM-1). Materials and Methods: A total of 256 clinical strains collected between 2019 and 2020 were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF). Antibiotic susceptibility testing was performed using disk diffusion and E-test methods. Real-time polymerase chain reaction (RT-PCR), standard PCR and sequencing were used to investigate genes encoding for extended-spectrum-β-lactamases, carbapenemases and colistin resistance genes. Conclusions: We report, for the first time, the presence of MDR-GNB clinical isolates and the emergence of carbapenem-resistant isolates in Djibouti. In addition to performing antimicrobial susceptibility testing, we recommend phenotypic and molecular screening to track the spread of carbapenemase genes among clinical GNB isolates.202337508230
92250.9999Insertion Sequences within Oxacillinases Genes as Molecular Determinants of Acinetobacter baumannii Resistance to Carbapenems-A Pilot Study. Carbapenem-resistant Acinetobacter baumannii is one of the major problems among hospitalized patients. The presence of multiple virulence factors results in bacteria persistence in the hospital environment. It facilitates bacterial transmission between patients, causing various types of infections, mostly ventilator-associated pneumonia and wound and bloodstream infections. A. baumannii has a variable number of resistance mechanisms, but the most commonly produced are carbapenem-hydrolyzing class D β-lactamases (CHDLs). In our study, the presence of bla(OXA-23), bla(OXA-40) and bla(OXA-51) genes was investigated among 88 clinical isolates of A. baumannii, including 53 (60.2%) strains resistant to both carbapenems (meropenem and imipenem) and 35 (39.8%) strains susceptible to at least meropenem. Among these bacteria, all the isolates carried the bla(OXA-51) gene. The bla(OXA-23) and bla(OXA-40) genes were detected in two (5.7%) and three (8.6%) strains, respectively. Among the OXA-23 carbapenemase-producing A. baumannii strains (n = 55), insertion sequences (ISAba1) were detected upstream of the bla(OXA-23) gene in fifty-two (94.5%) carbapenem-resistant and two (3.6%) meropenem-susceptible isolates. A. baumannii clinical strains from Poland have a similar antimicrobial resistance profile as those worldwide, with the presence of ISAba1 among bla(OXA-23)-positive isolates also being quite common. Carbapenem resistance among A. baumannii strains is associated with the presence of CHDLs, especially when insertion sequences are present.202439458366
212460.9999Evaluation of Phenotypic and Genotypic Characteristics of Carbapnemases-producing Enterobacteriaceae and Its Prevalence in a Referral Hospital in Tehran City. BACKGROUND & OBJECTIVE: Carbapenem-resistant Enterobacteriaceae is a growing concern worldwide including Iran. The emergence of this pathogen is worrying as carbapenem is one of the 'last-line' antibiotics for treatment of infections caused by multi drug resistant gram- negative bacteria. The main objective of this study was to determine the prevalence of carbapenem-resistant Enterobacteriaceae in a referral hospital in Tehran, Iran. METHODS: In this study, all positive isolates of Enterobacteriaceae recorded in blood, urine, and other body fluids were studied during April 2017 to April 2018 in a referral hospital in Tehran. All cases of resistance to carbapenems were first tested by modified Hodge test. All cases with positive or negative test, after gene extraction, were examined genotypically based on the primers designed for the three Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), and OXA-48 genes by conventional PCR method. RESULTS: 108 isolates (13.6%) were resistant to all cephalosporins as well as to imipenem and meropenem. In a genotypic study, including 45 isolates, 13 isolates were positive for OXA-48 gene, 11 isolates for OXA-48 and NDM genes, 11 isolates for OXA-48, NDM and KPC genes, 4 isolates for OXA-48 genes and KPC, 3 isolates for NDM, one isolate for KPC. On the other hand, two isolates were negative for all three genes examined. CONCLUSION: OXA-48 gene was one of the most common genes resistant to carbapenems in Iran. According to studies, the prevalence of antibiotic resistance in Iran is rising dramatically, which reduces the choice of antibiotics to treat severe infections in the future.202032215024
212270.9999Phenotypic and genotypic characteristics of carbapenemase- and extended spectrum β-lactamase-producing Klebsiella pneumoniae ozaenae clinical isolates within a hospital in Panama City. Klebsiella pneumoniae spp ozaenae is a versatile bacterial species able to acquire antimicrobial resistance; the species presents a higher antimicrobial resistance profile compared to Klebsiella pneumoniae spp pneumoniae. Carbapenemase and extended spectrum β-lactamase (ESBL)-producing bacteria commonly arise in clinical settings where antimicrobial stewardship is limited. Our study aims to report the phenotypical and genetic characteristics of nosocomial Klebsiella pneumoniae spp ozaenae isolates associated with mortality collected from a tertiary-level hospital in Panama City. In October 2020, 11 consecutive multidrug-resistant Gram-negative isolates were recovered from secretions and blood cultures from hospitalized patients. Nearly 90% (10/11) of these patients died, and bacteria was obtained from six patients for investigation. Biochemical evaluation of the six isolates revealed the presence of multidrug-resistant Klebsiella pneumoniae spp ozaenae. Phenotypic evaluation indicated resistance to carbapenemase and EBSL. In contrast, genetic evaluation by PCR showed that only 30% (2/6) were resistant to CTX-M-1 (CTX-M group 1), whereas 60.7% (4/6) presented carbapenemase resistance genes, and 33.3% (2/6) presented New Delhi metallo-β-lactamase (NDM) resistance genes. Klebsiella pneumoniae ST258 was identified in 83.3% (5/6) of the isolates. Phylogenetic analysis using 16S revealed low homology among the six isolates. These results suggest that antibiotic resistance genes may have been incorporated into these Klebsiella pneumoniae spp ozaenae isolates within the hospital environment. We recommend strengthening the antimicrobial stewardship program and antibiotic control policy, as well as heightened infection control and prevention measures, such as ward sanitation and increased hand washing frequency.202134733509
212380.9999Phenotypic and genotypic detection of resistance mechanisms in carbapenem-resistant gram-negative bacteria isolated from Egyptian ICU patients with first emergence of NDM-1 producing Klebsiella oxytoca. BACKGROUND AND OBJECTIVES: Carbapenems are considered the last resort to treat several infections, particularly in intensive care units (ICUs). However, increasing carbapenem resistance is problematic because it leads to high morbidity and mortality rates. This study aimed to determine the rate of carbapenem resistance among Gram-negative bacteria collected from patients in ICUs and to identify their resistance mechanisms using phenotypic and genotypic methods. MATERIALS AND METHODS: Antimicrobial susceptibility testing was carried out using the disc diffusion method among 180 Gram-negative bacterial isolates. Productions of carbapenemases, metallo-beta-lactamases (MBLs) and the harboring of carbapenemase-encoding genes, were detected in 40 selected carbapenem-resistant Gram-negative bacteria (CR-GNB). RESULTS: Of 40 selected CR-GNB isolates, 28 (70%), and 20 (50%) isolates were phenotypically positive for carbapenemase, and MBL production, respectively. Furthermore, 22 (55%) showed amplification of one or more of the carbapenemase-encoding genes, including bla (NDM-1), bla (VIM-2), and bla (OXA-48). This study described the first emergence of NDM-1 producing Klebsiella oxytoca in Egyptian ICUs. CONCLUSION: High incidence of CR-GNB detected in the ICUs in our study area may be attributed to the overuse of antibiotics, including carbapenems, and improper application of infection control measures. These findings confirm the need for the application of a strict antibiotic stewardship program.202236721446
211590.9999Assessment of carbapenemase genes and antibiotic resistance profiles in ceftazidime-avibactam resistant Klebsiella pneumoniae isolates: A single-center cross-sectional study. BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKp) is an urgent global health threat due to its rapid spread and limited treatment options. Ceftazidime-avibactam exhibits broad efficacy against gram-negative bacteria, including CRKp; however, emerging resistance to this agent is increasingly reported. Understanding the prevalence of ceftazidime-avibactam resistance and the underlying carbapenemase genes is critical for optimizing antimicrobial stewardship and guiding clinical management. This study aimed to determine the prevalence of ceftazidime avibactam resistance among CRKp isolates collected from various clinical specimens, and to analyze their associated carbapenemase genes and antibiotic resistance profiles. METHODS: This cross-sectional study analyzed 312 K pneumoniae isolates obtained from various clinical specimens of hospitalized patients at a tertiary care hospital in Turkey. Antibiotic susceptibility testing was performed using the disk diffusion method for ceftazidime-avibactam and broth microdilution for both colistin and ceftazidime-avibactam. Molecular detection of carbapenemase genes was carried out using polymerase chain reaction. RESULTS: Ceftazidime-avibactam resistance was identified in 21.5% (67/312) of CRKp isolates. Among these isolates, 37.3% harbored both OXA-48 and NDM genes, 13.4% carried NDM alone, 10.4% carried OXA-48 alone, and 38.8% lacked these genes. The majority of resistant isolates originated from urine (31.3%), followed by tracheal aspirate (29.9%), and blood (22.4%) specimens. The prevalence of colistin susceptibility among ceftazidime-avibactam-resistant CRKp isolates was 56.7%. CONCLUSIONS: The coexistence of NDM and OXA-48 genes is a major contributor to ceftazidime-avibactam resistance in CRKp isolates, particularly in urinary and respiratory tract infections. These findings underscore the need for ongoing surveillance and tailored antibiotic stewardship programs to control the spread of resistance in hospital settings.202541088587
2111100.9999Antimicrobial Resistance and Resistance Determinant Insights into Multi-Drug Resistant Gram-Negative Bacteria Isolates from Paediatric Patients in China. INTRODUCTION: The emergence of multi-drug-resistant Gram-negative bacteria (GNB) is a concern in China and globally. This study investigated antimicrobial resistance traits and resistance determinant detection in GNB isolates from paediatric patients in China. METHODS: In the present study, a total of 170 isolates of GNB including the most prevalent Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii were collected from Shenzhen Children's Hospital, China. ESBLs production was confirmed by using the combination disc diffusion method, and carbapenemase production was confirmed by using a carbapenem inactivation method followed by antimicrobial susceptibility. In addition, β-lactamase-encoding genes and co-existence of plasmid-borne colistin resistance mcr-1 gene were determined by PCR and sequencing. RESULTS: Overall, 170 etiological agents (GNB) were recovered from 158 paediatric patients. The most prevalent species was E. coli 40% (n=68), followed by K. pneumoniae 17.64% (n=30), and Enterobacter cloacae 14.11% (n=24). Of 170 GNB, 71.76% (n=122) were multi-drug-resistant, 12.35% (n=21) extreme-drug resistant, and 7.64% (n=13) single-drug-resistant, while 8.23% (n=14) were sensitive to all of the studied antibiotics. The prevalence of ESBLs and carbapenemase producers were 60% and 17%, respectively. bla (CTX-M) was the most prevalent resistance gene (59.42%), followed by bla (TEM) (41.17%), bla (SHV) (34.270%), bla (KPC) (34.11%), bla (OXA-48) (18.82%) and bla (NDM-1) (17.64%). CONCLUSION: The present study provides insights into the linkage between the resistance patterns of GNB to commonly used antibiotics and their uses in China. The findings are useful for understanding the genetics of resistance traits and difficulty in tackling of GNB in paediatric patients.201931819545
837110.9999Diversity of Carbapenem Resistance Mechanisms in Clinical Gram-Negative Bacteria in Pakistan. Antibiotic resistance is a health challenge worldwide. Carbapenem resistance in Gram-negative bacteria is a major problem since treatment options are very limited. Tigecycline and colistin are drugs of choice in this case, but resistance to these drugs is also high. The aim of this study was to describe the diversity of resistance mechanisms in carbapenem-resistant clinical Gram-negative bacteria from Pakistan. Carbapenem-hydrolyzing enzyme-encoding genes were detected using PCR and DNA sequencing and clonal types determined by multilocus sequence typing (MLST). Forty-four carbapenem-resistant isolates were collected from the microbiology laboratory of Fauji Foundation Hospital and Al-Syed Hospital, Rawalpindi, Pakistan, including Klebsiella spp., Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter cloacae, and Achromobacter xylosoxidans. bla(NDM-1), bla(NDM-4,) bla(NDM-5,) bla(NDM-7), bla(OXA-48), and bla(OXA-181) were detected in Enterobacteriaceae; bla(OXA-23,) bla(OXA-72), and bla(NDM-1) in A. baumannii, and bla(VIM-6) and bla(VIM-11) in P. aeruginosa. MLST analysis revealed several predominant clonal types: ST167 in E. coli, ST147 in Klebsiella pneumoniae, ST2 in Acinetobacter, and ST664 in P. aeruginosa. In Acinetobacter, a new clonal type was observed for the first time. To the best of our knowledge, this is the first study describing the clonality and resistance mechanisms of carbapenem-resistant Gram-negative bacteria in Pakistan.202133211640
1503120.9999OXA-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
996130.9999Rapid Detection of New Delhi Metallo-β-Lactamase Gene Using Recombinase-Aided Amplification Directly on Clinical Samples From Children. New Delhi metallo-β-lactamase, a metallo-β-lactamase carbapenemase type, mediates resistance to most β-lactam antibiotics including penicillins, cephalosporins, and carbapenems. Therefore, it is important to detect bla (NDM) genes in children's clinical samples as quickly as possible and analyze their characteristics. Here, a recombinase-aided amplification (RAA) assay, which operates in a single one-step reaction tube at 39°C in 5-15 min, was established to target bla (NDM) genes in children's clinical samples. The analytical sensitivity of the RAA assay was 20 copies, and the various bacterial types without bla (NDM) genes did not amplify. This method was used to detect bla (NDM) genes in 112 children's stool samples, 10 of which were tested positive by both RAA and standard PCR. To further investigate the characteristics of carbapenem-resistant bacteria carrying bla (NDM) in children, 15 carbapenem-resistant bacteria (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Citrobacter freundii, Klebsiella oxytoca, Acinetobacter junii, and Proteus mirabilis) were isolated from the 10 samples. Notably, more than one bacterial type was isolated from three samples. Most of these isolates were resistant to cephalosporins, cefoperazone-sulbactam, piperacillin-tazobactam, ticarcillin-clavulanic acid, aztreonam, co-trimoxazole, and carbapenems. bla (NDM) (-) (1) and bla (NDM) (-) (5) were the two main types in these samples. These data show that the RAA assay has potential to be a sensitive and rapid bla (NDM) gene screening test for clinical samples. The common existence of bla (NDM) and multi-drug resistance genes presents major challenges for pediatric treatment.202134367092
998140.9999Extended 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
1051150.9999Multi-drug Resistance, β-Lactamases Production, and Coexistence of bla (NDM-1) and mcr-1 in Escherichia coli Clinical Isolates From a Referral Hospital in Kathmandu, Nepal. The ability of pathogenic Escherichia coli to produce carbapenemase enzymes is a characteristic that allows them to resist various antibiotics, including last-resort antibiotics like colistin and carbapenem. Our objectives were to identify rapidly developing antibiotic resistance (AR), assess β-lactamases production, and detect mcr-1 and bla (NDM-1) genes in the isolates. A prospective cross-sectional study was carried out in a referral hospital located in Kathmandu from November 2019 to December 2020 using standard laboratory and molecular protocols. Among 77 total E. coli isolates, 64 (83.1%) of them were categorized as MDR. Phenotypically 13 (20.3%) colistin-resistant, 30 (46.9%) ESBL and 8 (12.5%) AmpC producers, and 5 (7.8%) ESBL/AmpC co-producers were distributed among MDR-E. coli. Minimum inhibitory concentrations (MIC) against the majority of MDR isolates were exhibited at 1 g/L. Of these 77 E. coli isolates, 24 (31.2%) were carbapenem-resistant. Among these carbapenem-resistant bacteria, 11 (45.9%) isolates were reported to be colistin-resistant, while 15 (62.5%) and 2 (8.3%) were MBL and KPC producers, respectively. Out of 15 MBL producers, 6 (40%) harbored bla (NDM-1), and 8 (61.5%) out of 13 colistin-resistant pathogens possessed mcr-1. The resistance by colistin- and carbapenem were statistically associated (P < .001). However, only 2 (18.2%) of the co-resistant bacteria were found to have both genes. Our study revealed the highly prevalent MDR and the carbapenem-resistant E. coli and emphasized that the pathogens possess a wide range of capabilities to synthesize β-lactamases. These findings could assist to expand the understanding of AR in terms of enzyme production.202336741474
994160.9999Moroccan 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
2118170.9999Gram-negative bacteria as causative agents of ventilator-associated pneumonia and their respective resistance mechanisms. Ventilator-associated pneumonia (VAP) is a serious and common complication in patients admitted to intensive care unit (ICU) and contributes to mortality. Multidrug Gram-negative bacteria such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae are frequently associated with VAP in ICU. A prospective study was set up in three ICUs of the University Hospital Center Zagreb and one ICU in General Hospital Pula from September 2017 to March 2018. Antibiotic susceptibility was determined by broth microdilution method. Production of extended-spectrum β-lactamases (ESBLs) was determined by double-disk synergy test and carbapenemases by Hodge and carbapenem inactivation method (CIM). The genes encoding ESBLs, carbapenemases of class A, B and D and qnr genes were determined by PCR. In total 97 Gram-negative bacteria isolates were analyzed. P. aeruginosa demonstrated high resistance rates for imipenem and meropenem with 74% and 68% of resistant strains, respectively. Moderate resistance rates were observed for ceftazidime andpiperacillin/tazobactam, ciprofloxacin and gentamicin (44%). All except three A. baumannii isolates, were resistant to carbapenems and to all other antibiotics apart from colistin and amikacin. Eight A. baumannii isolates were positive for bla(OXA-23) and 12 for bla(OXA-24) genes. Four K. pneumoniae and two E. cloacae strains were ESBL positive and harboured group 1 of CTX-M β-lactamases. Three P. mirabilis strains were positive for plasmid-mediated ampC β-lactamase of CMY family. Two carbapenem-resistant K. pneumoniae harboured OXA-48 and one carbapenem-resistant E. cloacae VIM-1. A high proportion of multidrug-resistant P. aeruginosa, K. pneumoniae and extensively resistant A. baumannii was reported. Acquired resistance mechanisms, mainly production of carbapenemases and ESBLs were dominant in A. baumannii and K. pneumoniae, respectively. Resistance of P. aeruginosa isolates was more likely due to upregulation of efflux pumps or porin loss. A marked diversity of β-lactamases was identified in Enterobacteriaceae.202032729399
2116180.9998Antibiotic Resistance Genes Among Carbapenem-resistant Enterobacterales (CRE) Isolates of Prapokklao Hospital, Chanthaburi Province, Thailand. BACKGROUND: The global spread of carbapenem-resistant Enterobacterales (CRE) inflicts a severe threat to human health. The CRE infections have resulted in an increased mortality rate in hospitals and other health-care settings worldwide. In this study, the antibiotic-resistance pattern and prevalence of carbapenemase-encoding genes among CRE isolated from patients of one hospital in Thailand were investigated. METHODS: By using conventional biochemical tests, we identified and isolated all species of Enterobacterales from the clinical samples kept at Prapokklao Hospital, Chanthaburi, Thailand, which were collected during 2016-2017. Multidrug-resistant (MDR) bacteria were determined by disc diffusion method and minimum inhibitory concentration (MIC) test strips. Carbapenemase genes were detected by PCR and confirmed by Sanger sequencing. RESULTS: Klebsiella pneumoniae complex, Escherichia coli, and Enterobacter spp. were isolated from the specimens. Of 9,564 isolated Enterobacterales, 282 were multidrug-resistance (MDR). The MIC test strips revealed that the MDR CRE were resistant to ertapenem (92.9%) and meropenem (81.3%). All these isolates carried carbapenemase-coding genes, including bla (NDM) (90%) and bla (IMP) (71%), the two most commonly found genes among CRE strains. There were 39.2% of the isolates that carried a combination of bla (NDM)-bla (IMP) and 22.6% carried combined bla (NDM)-bla (IMP)-bla (OXA-48-like) genes. CONCLUSION: This study demonstrates a significantly high prevalence of CRE isolates with the MDR phenotypes. A minority of the isolates carried a single carbapenem-resistant gene, while the majority harbored multiple genes in combination. Regular monitoring of MDR CRE and characterization of their drug resistance are important for guiding treatment, intervention and control of the CRE spread and outbreak in a health-care setting.202134511940
2119190.9998Detection of bla(IMP) and bla(VIM) metallo-β-lactamases genes among Pseudomonas aeruginosa strains. Acquired Metallo-β-Lactamases (MBLs) are emerging resistance determinants in Pseudomonas aeruginosa and other gram-negative bacteria.Using Combination Disk Diffusion test, it was found that among 83 imipenem non-susceptible P. aeruginosa strains, 48 (57.9%) were MBL producers. PCR and Sequencing methods proved that these isolates were positive for blaIMP-1 genes, whereas none were positive for bla(VIM) genes. The mortality rate due to MBL-producing Pseudomonas infection was 4 (8.3%) among the hospitalized patients. Therefore, identification of drug resistance patterns in P. aeruginosa and detection of MBLs producing isolates are of great importance in the prevention and control of infections.201323638331