The epidemiology and microbiological characteristics of infections caused by Gram-negative bacteria in Qatar: national surveillance from the Study for Monitoring of Antimicrobial Resistance Trends (SMART): 2017 to 2019. - Related Documents




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211301.0000The epidemiology and microbiological characteristics of infections caused by Gram-negative bacteria in Qatar: national surveillance from the Study for Monitoring of Antimicrobial Resistance Trends (SMART): 2017 to 2019. BACKGROUND: The global Study of Monitoring Antimicrobial Resistance Trends (SMART) is a surveillance program for evaluation of antimicrobial resistance (AMR) in Gram-negative bacteria (GNB) from different regions including Gulf countries. OBJECTIVES: To evaluate AMR in GNB from various clinical specimens including microbiological and genetic characteristics for existing and novel antimicrobials. METHODS: A prospective study was conducted on clinical specimens from Hamad Medical Corporation, Qatar, between 2017 and 2019 according to the SMART protocol. Consecutive GNB from different sites were evaluated including lower respiratory, urinary tract, intrabdominal and bloodstream infections. RESULTS: Over the 3 years study period, 748 isolates were evaluated from the specified sites comprising 37 different GNB outlining four key pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia.For the two major pathogens E. coli and K. pneumoniae, phenotypic ESBL was identified in 55.77% (116/208) compared to 39% (73/187), while meropenem resistance was 3.8% compared to 12.8% and imipenem/relebactam resistance was 2.97% compared to 11.76%, respectively. The overall ceftolozane/tazobactam resistance for E. coli was 9.6% (20/208) compared to 14.97% (28/187) for K. pneumoniae while resistance for ceftazidime/avibactam was 3.65% (5/137) and 5.98% (10/117), respectively. Genomic characteristics of 70 Enterobacterales including 48 carbapenem-resistant, revealed prevalence of β-lactamases from all classes, predominated by bla(CXM-15) while carbapenem resistance revealed paucity of bla(KPC) and dominance of bla(OXA-48) and bla(NDM) resistance genes. CONCLUSIONS: Surveillance of GNB from Qatar showed prevalence of key pathogens similar to other regions but demonstrated significant resistance patterns to existing and novel antimicrobials with different underlying resistance mechanisms.202337546546
212010.9999Antimicrobial 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
211120.9999Antimicrobial 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
211230.9999Multidrug-resistant gram-negative bacteria in ICU patients of a tertiary care hospital in Saudi Arabia: distribution of carbapenemase genes in clinical and rectal swab samples. Antimicrobial resistance among Gram-negative bacteria is a growing clinical challenge. This study aimed to assess bacterial distribution, antimicrobial susceptibility, and carbapenemase gene prevalence in clinical isolates. A total of 154 patients (mean age: 57.51 ± 18.75 years) were included. Specimens were primarily sputum (42.2%), blood (22.7%), and urine (18.8%). Bacterial isolates included K pneumoniae (43.8%), A. baumannii (24%), and P. aeruginosa (13.5%). Antimicrobial susceptibility testing (AST) was conducted to evaluate resistance patterns. MDR was detected, with alarming resistance to carbapenems, β-lactams, and fluoroquinolones. A. baumannii and P. aeruginosa exhibited near-total resistance to Imipenem (IPM), Meropenem (MRP), and Ertapenem (ETP), indicating extensive drug resistance (XDR). K. pneumoniae demonstrated exceptionally high resistance to carbapenems (IPM: 90.5%, MRP: 92.9%) and β-lactam antibacterial drugs (> 90%). Fluoroquinolone resistance exceeded 90% for Ciprofloxacin and Levofloxacin in A. baumannii, P. aeruginosa, and K. pneumoniae. Aminoglycosides, particularly Gentamicin, showed moderate resistance (A. baumannii: 87%, P. aeruginosa: 69.2%). Tigecycline remained one of the few viable treatment options against K. pneumoniae. Biofilm formation was significant, with 63.6% of isolates producing biofilm, particularly P. aeruginosa (80.9%), K. pneumoniae (67.2%), and A. baumannii (48.6%), increasing their pathogenic potential. Carbapenemase production was detected in 42.9% of isolates. The most prevalent genes were blaOXA- 48 (15.6%), blaNDM (8.4%), and blaVIM (7.1%), with co-expression in 9.7% of isolates. K. pneumoniae exhibited the highest risk for carbapenemase production (OR: 4.23, p < 0.001), whereas A. baumannii had a significantly lower risk (OR: 0.20, p = 0.005). Screening swabs showed more OXA- 48 (42.1%), while clinical isolates had more NDM and VIM. Alternative resistance mechanisms were suggested in 57.3% of clinical cases. The overwhelming prevalence of MDR and Carbapenem resistance among Gram-negative bacteria, particularly K. pneumoniae and A. baumannii, emphasizes an urgent need for strict antimicrobial stewardship, advanced infection control strategies, and novel therapeutic interventions to combat resistance spread.202540272517
212640.9999Carbapenemase 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
105150.9998Multi-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
211060.9998First report of carbapenems encoding multidrug-resistant gram-negative bacteria from a pediatric hospital in Gaza Strip, Palestine. BACKGROUND: The worldwide prevalence of multi-drug resistance (MDR) in Gram-negative bacteria (GNB), particularly related to extended-spectrum beta-lactamases (ESBLs) and carbapenemases, poses significant global public health and clinical challenges. OBJECTIVES: To characterize ESBL-producing Gram-negative bacilli, within a pediatric hospital in Gaza using whole genome sequencing (WGS). METHODS: A total of 158 clinical isolates of Gram-negative bacilli were collected from Al-Nasser Pediatric Hospital. These isolates were tested for ESBL production using the double disk synergy test. The antibiotic susceptibility profile was determined using the Kirby Bauer method following the Clinical and Laboratory Standard Institute guidelines. Selected 15 phenotypically MDR isolates were whole-genome sequenced and characterized for their genome-based species identity and antibiotic resistance gene profile. RESULTS: Of the 158 isolates, 93 (58.9%) were positive for ESBL production. The frequency of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, and Serratia marcescens was 50%, 22.7%, 22.7%, 1.8%, 1.2%, and 1.2% respectively. The prevalence of ESBL among urine, pus, blood, and sputum was 64%, 44%, 23%, and 63.6%, respectively. Chloramphenicol, Imipenem, and Meropenem were the most effective antibiotics against ESBL producers. In sequenced isolates,  an average of six anti-microbial resistance (AMR) genes were noted per isolate, where one of them carried up to 13 antibiotic resistance genes. Carbapenem resistance genes such as bla(KPC-2)(6.6%), bla(PDC-36/12) (6.6%), and bla(POM-1) (6.6%) were detected. All the sequenced E. coli isolates (n = 8) showed multiple resistance genes, mainly against β-lactamase (25.0%), aminoglycosides (37.5%), sulfonamides (37.5%), and genes conferring resistance to tetracyclines (25.0). CONCLUSION: Our results showed a high prevalence of ESBL-producing GNB isolated from a pediatric hospital in the Gaza Strip. Various antibiotic resistance genes were identified, including those encoding ESBL and carbapenems. The results highlight the significant challenge posed by MDR in GNB and emphasize the need for effective antibiotic strategies. Given the high endemicity observed in various studies from Palestine, it is important to conduct clinical and molecular epidemiology research to identify risk factors, transmission patterns, and clinical outcomes associated with GNB strains that carry ESBL and carbapenem resistance genes.202439379824
212470.9998Evaluation 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
92380.9998Prevalence of Oxacillinase Genes in Clinical Multidrug-Resistant Gram-Negative Bacteria. BACKGROUND: The emergence of OXA-type beta-lactamases has become a significant threat to public healthcare systems and may lead to prolonged hospital stays and increased mortality rates among affected patients. This study aimed to determine the prevalence of oxacillinase resistance (OXA) genes in multidrug-resistant (MDR) Gram-negative bacteria. METHODS: One hundred and six clinical isolates were collected from a stock of Gram-negative isolates and were identified and tested for antibiotic susceptibility and presence of OXA genes using polymerase chain reaction (PCR). RESULTS: The most common detected isolate was Klebsiella pneumoniae (36.8%), followed by Escherichia coli (33%), Pseudomonas aeruginosa (16%), and Acinetobacter baumannii (14.2%). Out of these isolates, 97.4%, 87.2%, 84.6%, and 79.5% were resistant to ampicillin/sulbactam, cefotaxime, ceftazidime, and aztreonam, respectively. PCR results confirmed the presence of one or more OXA genes in 34% of the samples studied. The blaOXA-1 and blaOXA-10 genes were the most highly detected genes, followed by blaOXA-4 and blaOXA-51. The total number of Pseudomonas aeruginosa isolates was confirmed to carry at least one OXA gene (70.6%), whereas Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli were confirmed to carry at least one OXA gene (53.3, 28.2, and 22.9%, respectively). There was a significant association (p < 0.05) between the resistance genes and the type of isolate. CONCLUSIONS: Pseudomonas aeruginosa and Acinetobacter baumannii are the most common MDR Gram-negative strains carrying OXA-type beta-lactamase genes. Monitoring of MDR pathogens in Gram-negative bacteria must be continuously undertaken to implement effective measures for infection control and prevention.202540066541
212790.9998Molecular 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
949100.9998Molecular and clinical insights into extended-spectrum β-lactamase genes of Klebsiella pneumoniae isolated from neonatal sepsis in Ethiopia. BACKGROUND: Klebsiella bacterial strains harboring Extended-Spectrum Beta-Lactamase (ESBL) enzymes are the primary culprits behind neonatal sepsis globally. These strains significantly impact clinical outcomes due to their multi-drug resistance patterns in local healthcare settings. In response to this spiraling threat, we studied the prevalence and clinical implications of ESBL-encoding genes in neonates hospitalized with confirmed sepsis. METHODS: A correlational study was conducted on 51 neonates diagnosed with sepsis caused by ESBL-positive Klebsiella pneumoniae at Jimma Medical Center spanning from May 2022 to July 2023. Antimicrobial resistance profiles of the bacterial isolates were determined using the Kirby-Bauer diffusion test, while multiplex polymerase chain reaction (mPCR) techniques were employed to identify resistance genes. The correlation between resistance genes and treatment outcomes was analyzed using the phi coefficient (φ) with a significance level below 0.05. The data management was executed through the utilization of WHONET and STATA software platforms. RESULTS: The sample consisted of 26 (50.9%) male and the remaining 25 (49.1%) female neonates, with diverse clinical characteristics. All 51 Klebsiella pneumoniae isolates were 100% resistant to trimethoprim/sulfamethoxazole and ceftriaxone, but showed varying resistance profiles ranging from 30.8% to meropenem to 94.2% to ceftazidime. Notably, all isolates demonstrated multidrug resistance, with 23% of cases showing resistance to seven different antimicrobial classes. The most prevalent resistance genes identified were bla(CTX-M) (96.1%), bla(TEM) (94.1%), and bla(SHV) (88.2%). The majority of isolates (94.1%) carried at least two resistance genes, such as bla(TEM) and bla(CTX) (94.1%), bla(TEM) and bla(SHV) (86.2%), and bla(CTX) and bla(SHV) (86.2%). Notably, 84.3% of the bacteria harbored the trio of bla(TEM), bla(CTX), and bla(SHV) resistance genes, and only the presence of bla(SHV) in monogenic (φ = 0.4, P = 0.01) or the trio of bla(TEM), bla(CTX), and bla(SHV) genes (φ = 0.3, P = 0.02) showed positive correlation with neonatal mortality. CONCLUSION: We observed a significant prevalence of multidrug-resistant Klebsiella pneumoniae strains among neonates. Moreover, ESBL-resistance genes were widespread, with the blaSHV gene showing a correlation with increased neonatal mortality. These findings emphasize the urgent need for enhanced infection prevention measures, robust antimicrobial resistance surveillance, innovative treatment strategies, antibiotic stewardship initiatives, further research into resistance transfer mechanisms as well as hierarchical predictors of neonatal mortality. CLINICAL TRIAL NUMBER: Not applicable.202439695444
2121110.9998Investigation 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
2115120.9998Assessment 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
997130.9998Prevalence 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
2122140.9998Phenotypic 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
922150.9998Insertion 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
2174160.9998Frequency of Beta-Lactamase Antibiotic Resistance Genes in Escherichia Coli and Klebsiella pneumoniae. BACKGROUND: This cross-sectional study was performed on isolates of Klebsiella pneumoniae, and E.coli from clinical specimens of patients admitted to Sayyad Shirazi Hospital by census sampling method in 2019. Antibiogram testing was performed using the disk diffusion method as defined by the Clinical and Laboratory Standards Organization for performing this test. Finally, the abundance of genes was evaluated by PCR using specific primers. Frequency, percentage, mean±SD were used to describe the data. Chi-square and Fisher's exact tests were used to compare the presence and absence of the studied genes alone and in the presence of each other. RESULT: This study was performed on 130 positive samples, isolated from 32 (24.6%) males and 98 (65.4%) females with a mean age of 43.78 ± 21.72. From the total number of 130 isolates, 84 (64.6%) consisted of E.coli, and 46 (35.4%) were Klebsiella. Most of the cultures were urine and vaginal (61.5%). The highest antibiotic resistance in isolates was cephalexin and cefazolin (67.9% in E.coli & 63% in Klebsiella). Colistin was identified as the most effective antibiotic (100%) in both. AMPC extendedspectrum β-lactamase genes were present in 40 (30.8%) isolates. The highest frequency about the gene pattern of AMPC positive β-lactamase bacteria was correlated to DHA, FOX, and CIT genes, while none of the samples contained the MOX β-lactamase gene. E.coli and Klebsiella beta-lactamase-producing AMPC isolates were also significantly correlated with antibiotic resistance to the cephalosporin class (P <0.05). CONCLUSION: This study indicated a high percentage of resistance to third and fourth generation cephalosporins. Hence, careful antibiogram tests and prevention of antibiotic overuse in infections caused by AMPC-producing organisms and screening of clinical samples for the resistance mentioned above genes and providing effective strategies to help diagnose and apply appropriate treatments and change antibiotic usage strategies can partially prevent the transmission of this resistance.202134483624
2114170.9998Clinical, phenotypic, and genotypic characteristics of ESBL-producing Salmonella enterica bloodstream infections from Qatar. BACKGROUND: Resistant Salmonella infections are a major global public health challenge particularly for multidrug-resistant (MDR) isolates manifesting as bloodstream infections (BSIs). OBJECTIVES: To evaluate clinical, phenotypic, and genotypic characteristics of extended-spectrum beta-lactamase (ESBL) producing Salmonella enterica BSIs from Qatar. METHODS: Phenotypic ESBL Salmonella enterica from adult patients presenting with positive BSIs were collected between January 2019 to May 2020. Microbiological identification and characterization were performed using standard methods while genetic characteristics were examined through whole genome sequencing studies. RESULTS: Of 151 episodes of Salmonella enterica BSI, 15 (10%) phenotypic ESBL isolates were collected. Recent travel was recorded in most cases (80%) with recent exposure to antimicrobials (27%). High-level resistance to quinolines, aminoglycosides, and cephalosporins was recorded (80-100%) while meropenem, tigecycline and colistin demonstrated universal susceptibility. Genomic evaluation demonstrated dominance of serotype Salmonella Typhi sequence type 1 (93%) while antimicrobial resistance genes revealed dominance of aminoglycoside resistance (100%), qnrS1 quinolones resistance (80%), bla(CTX-M-15) ESBLs (86.7%), and paucity of AmpC resistance genes (6.7%). CONCLUSIONS: Invasive MDR Salmonella enterica is mainly imported, connected to patients from high prevalent regions with recent travel and antimicrobial use caused by specific resistant clones. In suspected cases of multidrug resistance, carbapenem therapy is recommended.202438742235
924180.9998Screening of Antimicrobial Resistance Genes and Epidemiological Features in Hospital and Community-Associated Carbapenem-Resistant Pseudomonas aeruginosa Infections. INTRODUCTION: Researching carbapenem-resistant isolates enables the identification of carbapenemase-producing bacteria and prevents their spread. METHODS: P. aeruginosa isolates were recovered from Medicine Faculty of Recep Tayyip Erdoğan University and identified by conventional methods and the automated Vitek 2 Compact system. Antimicrobial susceptibility experiments were performed in accordance with CLSI criteria and the automated Vitek 2 Compact system. The PCR method was investigated for the presence of β-lactamase resistance genes. PFGE typing was performed to show clonal relation among samples. RESULTS: Seventy P. aeruginosa isolates were isolated from seventy patients. Of the patients, 67.1% had contact with the health service in the last 90 days and 75.7% of the patients had received antimicrobial therapy in the previous 90 days. Twenty-four isolates were carbapenem resistant, 2 isolates were multidrug-resistant except colistin, and none of the samples had colistin resistance. The gene encoding β-lactamase or metallo-β-lactamase was found in a total of 36 isolates. The bla (VEB) and bla (PER) genes were identified in 1 and 5 isolates alone or 17 and 13 isolates in combination with other resistance genes, respectively. The bla (NDM) was the most detected metallo-β-lactamase encoding gene (n=18), followed by bla (KPC) (n=12). bla (IMP) and bla (VIM) were detected in 5 and 1 isolates, respectively. Also, the association of bla (VEB)-bla (PER) and bla (VEB)-bla (KPC)-bla (NDM) was found to be very high. Much more resistance genes and co-occurrence were detected in hospital-acquired samples than community-acquired samples. No difference was found between the community and hospital-associated isolates according to PFGE results. Simultaneously from 6 patients, other microorganisms were also isolated and 5 of them died. CONCLUSION: The average length of stay (days) was found to be significantly higher in HAI group than CAI group. The death of 5 patients with fewer or no resistance genes showed that the co-existence of other microorganisms in addition to resistance genes was important on death.202133907430
998190.9998Extended 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