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147400.9912Simple, rapid, and cost-effective modified Carba NP test for carbapenemase detection among Gram-negative bacteria. PURPOSE: Detection of carbapenemases among Gram-negative bacteria (GNB) is important for both clinicians and infection control practitioners. The Clinical and Laboratory Standards Institute recommends Carba NP (CNP) as confirmatory test for carbapenemase production. The reagents required for CNP test are costly and hence the test cannot be performed on a routine basis. The present study evaluates modifications of CNP test for rapid detection of carbapenemases among GNB. MATERIALS AND METHODS: The GNB were screened for carbapenemase production using CNP, CarbAcineto NP (CANP), and modified CNP (mCNP) test. A multiplex polymerase chain reaction (PCR) was performed on all the carbapenem-resistant bacteria for carbapenemase genes. The results of three phenotypic tests were compared with PCR. RESULTS: A total of 765 gram negative bacteria were screened for carbapenem resistance. Carbapenem resistance was found in 144 GNB. The metallo-β-lactamases were most common carbapenemases followed by OXA-48-like enzymes. The CANP test was most sensitive (80.6%) for carbapenemases detection. The mCNP test was 62.1% sensitive for detection of carbapenemases. The mCNP, CNP, and CANP tests were equally sensitive (95%) for detection of NDM enzymes among Enterobacteriaceae. The mCNP test had poor sensitivity for detection of OXA-48-like enzymes. CONCLUSION: The mCNP test was rapid, cost-effective, and easily adoptable on routine basis. The early detection of carbapenemases using mCNP test will help in preventing the spread of multidrug-resistant organisms in the hospital settings.201728966495
140210.9906Detection of β-lactam resistance genes in Gram-negative bacteria from positive blood cultures using a microchip-based molecular assay. BACKGROUND: Accurate detection of β-lactam resistance genes in bloodstream infections is critical for guiding antimicrobial therapy. This study evaluates the Alifax Gram-negative resistance (GNR) microchip assay for detecting β-lactam resistance genes directly from positive blood cultures (PBCs) for Gram-negative (GN) bacteria, including Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii. METHODS: Simulated (n=146) and clinical (n=106) GN-PBC samples were tested for bla (KPC), bla (VIM), bla (NDM), bla (IMP), bla (OXA-23)-like, bla (OXA-48)-like, bla (SHV)-ESBL, bla (CTX-M-1/9) group, and bla (CMY-2)-like genes using the GNR microchip assay. Whole-genome sequencing (WGS) served as the reference assay for simulated samples and, selectively, for clinical samples. The bioMérieux BioFire Blood Culture Identification 2 (BCID2) panel assay was used as a comparator for clinical samples. RESULTS: The GNR microchip assay correctly identified 203 (99.5%) of 204 β-lactam resistance genes in simulated samples. One sample tested false negative for a bla (SHV)-ESBL gene but true positive for a bla (KPC) gene. In clinical samples, GNR results were concordant with BCID2 for 113 (100%) of 113 genes included in both assays. Additionally, the GNR assay detected bla (CMY-2) -like (n=6), bla (OXA-23)-like (n=5), and bla (SHV)-ESBL (n=2), which are not targeted by BCID2, all confirmed by WGS. In two β-lactam-resistant P. aeruginosa samples but negative by the GNR assay, WGS confirmed the absence of acquired β-lactam resistance genes, suggesting alternative resistance mechanisms. CONCLUSION: The GNR microchip assay demonstrated high concordance and broader β-lactam resistance gene coverage compared to BCID2, supporting its potential role in routine diagnostics. Further validation in larger, prospective studies is warranted.202540529307
142620.9904Phenotypic and genotypic detection of carbapenemase production among gram negative bacteria isolated from hospital acquired infections. OBJECTIVES: To identify the carbapenemase producing Gram-negative bacteria (GNB) by phenotypic methods and to confirm the presence of resistant genes using real-time polymerase chain reaction (PCR). METHODS: This was a prospective study carried out at the Department of Microbiology, Sri Venkata Sai Medical College and Hospital, Mahabubnagar, India, from March 2018-2021. All samples were screened for carbapenem resistance by disc diffusion method and the VITEK(®)2 compact system (bioMérieux, France). Detection of carbapenemase was carried out using RAPIDEC(®)CARBA NP test (Biomeriux Private Limited, South Delhi, India), screening for metallo-β-lactamases (MBL) was carried out by double disk synergy test (DDST), and genotypic characterization by real-time PCR. RESULTS: Among the 1093 Gram-negative bacilli identified, 220 (17.0%) were resistant to carbapenems by both tested methods. Carbapenemase detection using the RAPIDEC(®)CARBA NP test indicated that 207 (94.0%) were carbapenemase producers, of which 189 (91.2%) were MBL producers. The most common carbapenemase genes identified were New Delhi metallo-β-lactamase (NDM; 47.3%), followed by the co-existence of genes in combination of NDM, with Verona integron-mediated metallo-β-lactamase (VIM; 39.6%), VIM and oxacillin hydrolyzing enzymes-48 (OXA-48; 4.3%), and OXA-48 (1.4%).No gene of active on imipenem, Klebsiella pneumonia carbapenemase, VIM, or OXA-48 alone was detected. CONCLUSION: This study suggests routine carbapenem resistance testing among multi-drug resistant-GNBs, as most of these infections occur in hospitals. In addition, there is a possibility that these highly antibiotic-resistant genes could spread to other bacteria resulting in further dissemination.202235256490
140530.9903The threat of carbapenem resistance in Eastern Europe in patients with decompensated cirrhosis admitted to intensive care unit. BACKGROUND: Multidrug-resistant organisms are an increasing concern in patients with decompensated cirrhosis. AIM: We aimed to evaluate the prevalence of infections with carbapenem-resistant Enterobacteriaceae in patients with decompensated cirrhosis. METHODS: Patients with decompensated cirrhosis admitted to ICU were included. The isolated Enterobacteriaceae strains were tested for carbapenemase-producing genes using the Roche LightMix® Modular VIM/IMP/NDM/GES/KPC/OXA48-carbapenemase detection kit. RESULTS: 48 culture-positive infections were registered in 75 patients with acutely decompensated cirrhosis. Thirty patients contracted a second infection. 46% of bacteria isolated at admission and 60% of bacteria responsible for infections identified during ICU-stay were multiresistant. ESBL+ Enterobacteriaceae were predominant at admission, while carbapenem-resistance was dominant in both Enterobacteriaceae and Non-Fermenting-Gram-Negative Bacteria responsible for infections diagnosed during hospitalisation. OXA 48 or KPC type carbapenemases were present in 30% of the analyzed Enterobacteriaceae and in 40% of the phenotypically carbapenem-resistant Klebsiella pneumoniae strains. The length of ICU stay was a risk-factor for a second infection (p=0.04). Previous carbapenem usage was associated with occurence of infections with carbapenem-resistant Gram-negative bacteria during hospitalization (p=0.03). CONCLUSION: The prevalence of infections with carbapenem-resistant Enterobacteriaceae is high in patients with decompensated cirrhosis admitted to ICU. Carbapenemase-producing genes in Enterobacteriaceae in our center are bla(OXA-48) and bla(KPC).202235732546
140340.9903Evaluation of the AusDiagnostics MT CRE EU assay for the detection of carbapenemase genes and transferable colistin resistance determinants mcr-1/-2 in MDR Gram-negative bacteria. OBJECTIVES: To evaluate the AusDiagnostics MT CRE EU assay for the detection of carbapenemase and acquired colistin resistance genes in Gram-negative bacteria. METHODS: The assay allows the detection of blaKPC, blaOXA-48-like, blaNDM, blaVIM, blaIMP, blaSIM, blaGIM, blaSPM, blaFRI, blaIMI, blaGES (differentiating ESBL and carbapenemase variants), blaSME and mcr-1/-2. It was evaluated against a panel of isolates including Enterobacteriaceae, Pseudomonas spp. and Acinetobacter spp. retrospectively (n = 210) and prospectively (n = 182). RESULTS: The CRE EU assay was able to detect 268/268 carbapenemase genes, with 239 belonging to the 'big five' families (KPC, OXA-48-like, NDM, VIM and IMP) and 29 carbapenemase genes of the SIM, GIM, SPM, FRI, IMI, SME and GES families. It could distinguish between ESBL and carbapenemase variants of GES. It also allowed detection of mcr-1/-2 colistin resistance genes on their own or in isolates co-producing a carbapenemase. CONCLUSIONS: The AusDiagnostics MT CRE EU assay offered wide coverage for detection of acquired carbapenemase genes. It required minimal hands-on time and delivered results in less than 4 h from bacterial culture.201830189011
142550.9902Distribution and Antimicrobial Resistance of Complicated Intraabdominal Infection Pathogens in Two Tertiary Hospitals in Egypt. Background: Management of complicated intraabdominal infections (cIAIs) requires containment of the source and appropriate initial antimicrobial therapy. Identifying the local data is important to guide the empirical selection of antimicrobial therapy. In this study, we aimed to describe the pathogen distribution and antimicrobial resistance of cIAI. Methods: In two major tertiary care hospitals in Egypt, we enrolled patients who met the case definition of cIAI from October 2022 to September 2023. Blood cultures were performed using the BACTAlert system (BioMerieux, Marcy l'Etoile, France). A culture of aspirated fluid, resected material, or debridement of the infection site was performed. Identification of pathogens and antimicrobial susceptibility testing were conducted by the VITEK-2 system (BioMerieux, Marcy l'Etoile, France). Gram-negative resistance genes were identified by PCR and confirmed by whole bacterial genome sequencing using the Nextera XT DNA Library Preparation Kit and sequencing with the MiSeq Reagent Kit 600 v3 (Illumina, USA) on the Illumina MiSeq. Results: We enrolled 423 patients, 275 (65.01%) males. The median age was 61.35 (range 25-72 years). We studied 452 recovered bacterial isolates. Gram-negative bacteria were the vast majority, dominated by E. coli, followed by Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Proteus mirabilis (33.6%, 30.5%, 13.7%, 13%, and 5.4%, respectively). High rates of resistance were detected to third- and fourth-generation cephalosporins and fluoroquinolones. No resistance was detected to colistin. Resistance to amikacin and tigecycline was low among all isolates. Resistance to meropenem and ceftazidime/avibactam was moderate. ESBL genes were common in E. coli and K. pneumoniae. CTX-M15 gene was the most frequent. Among Enterobacterales, bla(OXA-48) and bla(NDM) were the most prevalent carbapenemase genes. Pseudomonas aeruginosa isolates harbored a wide variety of carbapenemase genes (OXA, NDM, VIM, SIM, GIM, SPM, IMP, AIM), dominated by metallo-beta-lactamases. In 20.6% of isolates, we identified two or more resistance genes. Conclusion: High resistance rates were detected to third- and fourth-generation cephalosporins and fluoroquinolones. Amikacin and tigecyclines were the most active antimicrobials. Our data call for urgent implementation of antimicrobial stewardship programs and reinforcement of infection control.202439172656
142860.9901Carbapenem-resistant Gram-negative bacteria associated with catheter-related bloodstream infections in three intensive care units in Egypt. We aimed to identify the carbapenem-resistant Gram-negative bacteria (GNB) causing catheter-related bloodstream infections (CRBSI) in intensive care units (ICU) in a tertiary care Egyptian hospital, to study their resistance mechanisms by phenotypic and genetic tests, and to use ERIC-PCR for assessing their relatedness. The study was conducted over 2 years in three ICUs in a tertiary care hospital in Egypt during 2015-2016. We identified 194 bloodstream infections (BSIs); 130 (67.01%) were caused by GNB, of which 57 were isolated from CRBSI patients (73.84%). Identification of isolates was performed using conventional methods and MALDI-TOF MS. Antimicrobial susceptibility testing (AST) was done by disc diffusion following CLSI guidelines. Phenotypic detection of carbapenemases enzymes activity was by modified Hodge test and the Carba-NP method. Isolates were investigated for the most common carbapenemases encoding genes bla(KPC), bla(NDM), and bla(OXA-48) using multiplex PCR. Molecular typing of carbapenem-resistant isolates was done by ERIC-PCR followed by sequencing of common resistance genes. The overall rate of CRBSI in our study was 3.6 per 1000 central venous catheter (CVC) days. Among 57 Gram-negative CRBSI isolates, Klebsiella pneumoniae (K. pneumoniae) was the most frequently isolated (27/57; 47.4%), of which more than 70% were resistant to Meropenem. Phenotypic tests for carbapenemases showed that 37.9% of isolates were positive by modified Hodge test and 63.8% by Carba-NP detection. Multiplex PCR assay detected the bla(NDM) in 28.6% of the isolates and bla(KPC) in 26.8%, bla(NDM) and bla(KPC) were detected together in the same isolate in 5.6%, while bla(OXA-48)-like were not detected. ERIC-PCR detected limited genetic relatedness between K. pneumoniae isolates. Elevated resistance rates were observed to all antibiotics including carbapenems among K. pneumoniae isolates causing CRBSI. ERIC-PCR showed that the resistant isolates were mainly polyclonal. Our results call for reinforcement of antimicrobial stewardship and measures to prevent CRBSI.201829936619
147870.9900Multicenter Evaluation of the FilmArray Blood Culture Identification 2 Panel for Pathogen Detection in Bloodstream Infections. The FilmArray Blood Culture Identification 2 panel (BCID2; bioMérieux) is a fully automated PCR-based assay for identifying bacteria, fungi, and bacterial resistance markers in positive blood cultures (BC) in about 1 h. In this multicenter study, we evaluated the performance of the BCID2 panel for pathogen detection in positive BC. Conventional culture and BCID2 were performed in parallel at four tertiary-care hospitals. We included 152 positive BC-130 monomicrobial and 22 polymicrobial cultures-in this analysis. The BCID2 assay correctly identified 90% (88/98) of Gram-negative and 89% (70/79) of Gram-positive bacteria. Five bacterial isolates targeted by the BCID2 panel and recovered from five positive BC, including three polymicrobial cultures, were missed by the BCID2 assay. Fifteen isolates were off-panel organisms, accounting for 8% (15/182) of the isolates obtained from BC. The mean positive percent agreement between the BCID2 assay and standard culture was 97% (95% confidence interval, 95 to 99%), with agreement ranging from 67% for Candida albicans to 100% for 17 targets included in the BCID2 panel. BCID2 also identified the bla(CTX-M) gene in seven BC, including one for which no extended-spectrum β-lactamase (ESBL)-producing isolate was obtained in culture. However, it failed to detect ESBL-encoding genes in three BC. Two of the 18 mecA/C genes detected by the BCID2 were not confirmed. No carbapenemase, mecA/C, or MREJ targets were detected. The median turnaround time was significantly shorter for BCID2 than for culture. The BCID2 panel may facilitate faster pathogen identification in bloodstream infections. IMPORTANCE Rapid molecular diagnosis combining the identification of pathogens and the detection of antibiotic resistance genes from positive blood cultures (BC) can improve the outcome for patients with bloodstream infections. The FilmArray BCID2 panel, an updated version of the original BCID, can detect 11 Gram-positive bacteria, 15 Gram-negative bacteria, 7 fungal pathogens, and 10 antimicrobial resistance genes directly from a positive BC. Here, we evaluated the real-life microbiological performance of the BCID2 assay in comparison to the results of standard methods used in routine practice at four tertiary care hospitals.202336519852
143080.9898Prevalence of multidrug-resistant Gram-negative bacteria from blood cultures and rapid detection of beta-lactamase-encoding genes by multiplex PCR assay. INTRODUCTION: This study aimed to determine the prevalence of multidrug-resistant Gram-negative bacteria (GNB) from blood cultures in a tertiary-care hospital and the multiplex PCR assay's ability to detect resistance genes. METHODS: A total of 388 GNB isolates obtained from hospitalized patients between November 2019 and November 2021 were included in the study. Antimicrobial susceptibility testing was done by VITEK 2 system and broth microdilution method. Beta-lactamase-encoding genes were detected by multiplex PCR assays, BioFire-Blood Culture Identification 2 (BCID2) panel (bioMérieux, France). Extended-spectrum beta-lactamases (ESBLs) were detected phenotypically with VITEK AST-GN71 card (bioMérieux, France). The isolates of GNB were classified into multidrug-resistant, extensively-drug-resistant, and pandrug-resistant categories, and their prevalence and distribution in different wards, including coronavirus diseases 2019 (COVID-19) intensive care units (ICU), were calculated. RESULTS: Results revealed that all isolates of Acinetobacter baumannii and Pseudomonas aeruginosa were multidrug-resistant as well as 91.6% of Enterobacter cloacae, 80.6% of Proteus mirabilis, and 76.1% of Klebsiella pneumoniae, respectively. In fermentative bacteria, bla(OXA-48-like) (58.1%), bla(NDM) (16.1%), bla(KPC) (9.7%) and bla(VIM) (6.5%) genes were detected. More than half of Enterobacter cloacae (58.3%) and Klebsiella pneumoniae (53.7%) produced ESBLs. Among non-fermenters, the bla(NDM) gene was carried by 55% of Pseudomonas aeruginosa and 19.5% of Acinetobacter baumannii. In the COVID-19 ICU, Acinetobacter baumannii was the most common isolate (86.1%). CONCLUSIONS: This study revealed high proportions of multidrug-resistant blood isolates and various underlying resistance genes in Gram-negative strains. The BCID2 panel seems to be helpful for the detection of the most prevalent resistance genes of fermentative bacteria.202238021186
222390.9897Evaluation of a new real-time PCR assay (Check-Direct CPE) for rapid detection of KPC, OXA-48, VIM, and NDM carbapenemases using spiked rectal swabs. To prevent the spread of carbapenemase-producing bacteria, a fast and accurate detection of patients carrying these bacteria is extremely important. The Check-Direct CPE assay (Check-Points, Wageningen, The Netherlands) is a new multiplex real-time PCR assay, which has been developed to detect and differentiate between the most prevalent carbapenemase genes encountered in Enterobacteriaceae (blaKPC, blaOXA-48, blaVIM, and blaNDM) directly from rectal swabs. Evaluation of this assay using 83 non-duplicate isolates demonstrated 100% sensitivity and specificity and the correct identification of the carbapenemase gene(s) present in all carbapenemase-producing isolates. Moreover, the limit of detection (LoD) of the real-time PCR assay in spiked rectal swabs was determined and showed comparable LoDs with the ChromID CARBA agar. With an excellent performance on clinical isolates and spiked rectal swabs, this assay appeared to be an accurate and rapid method to detect blaKPC, blaOXA-48, blaVIM, and blaNDM genes directly from a rectal screening swab.201324135412
1477100.9897Multicenter Evaluation of the BIOFIRE Blood Culture Identification 2 Panel for Detection of Bacteria, Yeasts, and Antimicrobial Resistance Genes in Positive Blood Culture Samples. Diagnostic tools that can rapidly identify and characterize microbes growing in blood cultures are important components of clinical microbiology practice because they help to provide timely information that can be used to optimize patient management. This publication describes the bioMérieux BIOFIRE Blood Culture Identification 2 (BCID2) Panel clinical study that was submitted to the U.S. Food & Drug Administration. Results obtained with the BIOFIRE BCID2 Panel were compared to standard-of-care (SoC) results, sequencing results, PCR results, and reference laboratory antimicrobial susceptibility testing results to evaluate the accuracy of its performance. Results for 1,093 retrospectively and prospectively collected positive blood culture samples were initially enrolled, and 1,074 samples met the study criteria and were included in the final analyses. The BIOFIRE BCID2 Panel demonstrated an overall sensitivity of 98.9% (1,712/1,731) and an overall specificity of 99.6% (33,592/33,711) for Gram-positive bacteria, Gram-negative bacteria and yeast targets which the panel is designed to detect. One hundred eighteen off-panel organisms, which the BIOFIRE BCID2 Panel is not designed to detect, were identified by SoC in 10.6% (114/1,074) of samples. The BIOFIRE BCID2 Panel also demonstrated an overall positive percent agreement (PPA) of 97.9% (325/332) and an overall negative percent agreement (NPA) of 99.9% (2,465/2,767) for antimicrobial resistance determinants which the panel is designed to detect. The presence or absence of resistance markers in Enterobacterales correlated closely with phenotypic susceptibility and resistance. We conclude that the BIOFIRE BCID2 Panel produced accurate results in this clinical trial.202337227281
2196110.9897Antibiotic resistance profiles in Gram-negative bacteria causing bloodstream and urinary tract infections in paediatric and adult patients in Ndola District, Zambia, 2020-2021. BACKGROUND: Bloodstream infections (BSIs) and urinary tract infections (UTIs) caused by antibiotic resistant bacteria (ARB) have unfavourable treatment outcomes and negative economic impacts. OBJECTIVES: The main objective of this study was to determine antibiotic resistance profiles in Gram-negative bacteria (GNB) causing BSIs and UTIs. METHOD: A prospective study from October 2020 to January 2021 at Ndola Teaching Hospital and Arthur Davison Children's Hospital in the Ndola district, Zambia. Blood and urine samples collected from inpatients and outpatients presenting with fever and/or urinary tract infection symptoms were submitted for microbiological analysis. Pathogen identification and antibiotic susceptibility was determined by the automated VITEK 2 Compact machine. Resistance genes to commonly used antibiotics were determined using polymerase chain reaction. Data were analysed using SPSS version 28.0. RESULTS: One hundred and ten GNB were isolated, E. coli (45.5%) was predominant, with varying resistance profiles to different antibiotic classes. Resistance to third-generation cephalosporin was highest in Enterobacter cloacae (75%) and Klebsiella pneumoniae (71%), respectively. Emergence of carbapenem resistance was noted with the highest being 17% in Acinetobacter baumannii. Notably, the prevalence of multi-drug resistance was 63% and extensively drug-resistance was 32%. Resistance gene determinants identified included bla (CTX-M,) qnrA and bla (NDM). CONCLUSION: High level antibiotic resistance was observed in GNB known to be prevalent causative agents of BSIs and UTIs locally in Zambia. Improving microbiology diagnostic capacity, strengthening antimicrobial stewardship programs and enforcing infection prevention and control measures are of utmost importance in promoting rational use of antibiotics and preventing the spread and emergence of resistant pathogens.202540585877
1488120.9897Evaluation of an automated rapid diagnostic assay for detection of Gram-negative bacteria and their drug-resistance genes in positive blood cultures. We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA), an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB) and for detection of 9 genes associated with β-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods), Citrobacter spp. (7/7), Escherichia coli (87/87), Klebsiella oxytoca (13/13), and Proteus spp. (11/11); Enterobacter spp. (29/30); Klebsiella pneumoniae (62/72); Pseudomonas aeruginosa (124/125); and Serratia marcescens (18/21); respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all β-lactam resistance genes tested (233 genes), including 54 bla(CTX-M), 119 bla(IMP), 8 bla(KPC), 16 bla(NDM), 24 bla(OXA-23), 1 bla(OXA-24/40), 1 bla(OXA-48), 4 bla(OXA-58), and 6 blaVIM. The data shows that the BC-GN assay provides rapid detection of GNB and β-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes.201424705449
1485130.9896Evaluation of Verigene Blood Culture Test Systems for Rapid Identification of Positive Blood Cultures. The performance of molecular tests using the Verigene Gram-Positive and Gram-Negative Blood Culture nucleic acid tests (BC-GP and BC-GN, resp.; Naosphere, Northbrook, IL, USA) was evaluated for the identification of microorganisms detected from blood cultures. Ninety-nine blood cultures containing Gram-positive bacteria and 150 containing Gram-negative bacteria were analyzed using the BC-GP and BC-GN assays, respectively. Blood cultures were performed using the Bactec blood culture system (BD Diagnostic Systems, Franklin Lakes, NJ, USA) and conventional identification and antibiotic-susceptibility tests were performed using a MicroScan system (Siemens, West Sacramento, CA, USA). When a single strain of bacteria was isolated from the blood culture, Verigene assays correctly identified 97.9% (94/96) of Gram-positive bacteria and 93.8% (137/146) of Gram-negative bacteria. Resistance genes mecA and vanA were correctly detected by the BC-GP assay, while the extended-spectrum β-lactamase CTX-M and the carbapenemase OXA resistance gene were detected from 30 cases cultures by the BC-GN assay. The BC-GP and BC-GN assays showed high agreement with conventional identification and susceptibility tests. These tests are useful for rapid identification of microorganisms and the detection of clinically important resistance genes from positive Bactec blood cultures.201626904669
1436140.9896Characterisation of carbapenem-resistant Gram-negative organisms from clinical specimens in Yola, Nigeria. OBJECTIVES: This study aimed to identify carbapenem-resistant Gram-negative bacteria from clinical specimens of patients in Yola, Nigeria. METHODS: Routine clinical specimens were screened for the presence of carbapenem-resistant Gram-negative bacteria using chromogenic agar plates. Susceptibility of all presumptive isolates to carbapenems was tested by MIC and disk diffusion methods. Real-time PCR was used to test for the presence of carbapenemase genes. RESULTS: Screening of 1741 clinical specimens yielded 119 (6.8%) presumptive carbapenem-resistant Gram-negative bacteria. Antimicrobial susceptibility testing confirmed carbapenem resistance in 105 of these isolates. New Delhi metallo-β-lactamase (bla(NDM)) gene was detected in 26 isolates and Verona integron-encoded metallo-β-lactamase (bla(VIM)) gene was detected in four. The mechanism of resistance could not be identified in approximately two thirds of the carbapenem-resistant isolates. CONCLUSION: While bla(NDM) and bla(VIM) accounted for 28.6% of the resistance seen, further molecular-based studies are needed to characterise the other mechanisms of carbapenem resistance in these isolates.202031472281
1459150.9894Molecular characterization of carbapenem-resistance in Gram-negative isolates obtained from clinical samples at Jimma Medical Center, Ethiopia. BACKGROUND: In resource-constrained settings, limited antibiotic options make treating carbapenem-resistant bacterial infections difficult for healthcare providers. This study aimed to assess carbapenemase expression in Gram-negative bacteria isolated from clinical samples in Jimma, Ethiopia. METHODS: A cross-sectional study was conducted to assess carbapenemase expression in Gram-negative bacteria isolated from patients attending Jimma Medical Center. Totally, 846 Gram-negative bacteria were isolated and identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Phenotypic antibiotic resistance patterns were determined using the Kirby-Bauer disk diffusion method and Etest strips. Extended-spectrum β-lactamase phenotype was determined using MAST disks, and carbapenemases were characterized using multiplex polymerase chain reactions (PCR). RESULTS: Among the isolates, 19% (157/846) showed phenotypic resistance to carbapenem antibiotics. PCR analysis revealed that at least one carbapenemase gene was detected in 69% (107/155) of these strains. The most frequently detected acquired genes were blaNDM in 35% (37/107), blaVIM in 24% (26/107), and blaKPC42 in 13% (14/107) of the isolates. Coexistence of two or more acquired genes was observed in 31% (33/107) of the isolates. The most common coexisting acquired genes were blaNDM + blaOXA-23, detected in 24% (8/33) of these isolates. No carbapenemase-encoding genes could be detected in 31% (48/155) of carbapenem-resistant isolates, with P. aeruginosa accounting for 85% (41/48) thereof. CONCLUSION: This study revealed high and incremental rates of carbapenem-resistant bacteria in clinical samples with various carbapenemase-encoding genes. This imposes a severe challenge to effective patient care in the context of already limited treatment options against Gram-negative bacterial infections in resource-constrained settings.202438328425
1462160.9893Phenotypic synergy testing of ceftazidime-avibactam with aztreonam in a university hospital having high number of metallobetalactamase producing bacteria. BACKGROUND: Ceftazidime-avibactam combination with aztreonam and role of rapid synergy reporting has not been widely evaluated. Also the synergy correlation with various betalactamases has not been widely studied. METHODS: We studied phenotypic synergy testings and molecular detection of betalactamases in our university hospital where we have large number of mellatobetalactmase producing bacteria. We tested two phenotypic synergy methods for ceftazidime-avibactam with aztreonam (Disc-E strip method, E strip-Agar method) for rapid reporting to clinicians (153 isolates). The treatment (colistin, ceftazidime-avibactam, ceftazidime-avibactam with aztreonam) was guided as indicated in the synergy testings. The resistance genes in bacteria were identified by polymerase chain reaction (PCR) and correlated with synergy results. RESULTS: The highest synergy was seen in Klebsiella pneumoniae by Disc-E strip and E strip-Agar method (86% and 84% respectively). About 70% of Pseudomonas aeruginosa and 29% of Escherichia coli showed synergy. Molecular methods revealed multiple resistance gene combinations and bla(NDM) (96%) was predominant gene in isolates showing synergy. Among isolates that were sensitive to ceftazidime-avibactam, the predominant genes were bla(OXA-48) and bla(IMP.) Rapid laboratory reporting led to proper utilization of antibiotic combinations. CONCLUSIONS: Ceftazidime-avibactam and aztreonam rapid synergy testing will be highly beneficial in treatment of infections by metallobetalactamase producing resistant bacteria, especially K. pneumoniae and P. aeruginosa.202032628575
1429170.9893Detection of blaKPC and blaGES Carbapenemase Genes in Klebsiella pneumoniae Isolated from Hospitalized Patients in Kashan, Iran. INTRODUCTION: Klebsiella pneumoniae carbapenemase (KPC)-producing bacteria are among the highly antimicrobial resistant gram negative bacteria and infections due to them are an increasingly major health problem worldwide. METHODS: In this study we have detected the blaKPC and blaGES carbapenemase genes in Klebsiella pneumoniae isolated from hospitalized patients in Kashan, Iran. In a cross-sectional study, a total of 181 K. pneumoniae isolates were recovered from clinical specimens during November 2013 to October 2014. RESULT: Antimicrobial susceptibility profiles were determined using disk diffusion method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and CLSI guidelines. Carbapenem-resistant K. pneumoniae isolates were identified. PCR method and sequencing were used for detection of blaKPC and blaGES carbapenemase genes. Of the 181 K. pneumoniae isolates, 35 (19.3%) were found to be resistant to imipenem and 150 (82.9%) were identified as MDR strains. Among carbapenems, the most resistant rate 39 (21.5%) was seen against ertapenem using disk diffusion method. Of K. pneumoniae isolates 21 (11.6%) and 42 (23.2%) carried blaKPC and blaGES genes, respectively and 19(10.5%) carried both genes simultaneously. CONCLUSION: The data of current study revealed that the frequency of resistance to carbapenems and production of carbapenemase enzymes especially GES type was high among clinical isolates of K pneumoniae in Kashan, Iran.201627527726
1418180.9893Nosocomial infections and antimicrobial susceptibility patterns among patients admitted to intensive care unit of Imam Khomeini hospital in Ilam, Iran. INTRODUCTION: Nosocomial infections (NIs) are a major challenge worldwide. Identification of antibiotic resistance pattern extended spectrum beta-lactamases (ESBLs) and carbapenem-resistant Enterobacteriaceae (CRE) were the objectives of this study. METHODS: In this cross-sectional study, the antimicrobial susceptibility pattern of bacterial isolates collected from patients with NIs in ICU was determined. Overall, 42 Escherichia coli and Klebsiella pneumoniae isolates from different infection sites were used to determine phenotypic tests of ESBLs, Metallo-β-lactamases (MBLs) and CRE. Detection of ESBLs, MBLs and CRE genes were performed by the polymerase chain reaction (PCR) method. RESULTS: From 71 patients with NIs, 103 different bacterial strains were isolated. The most frequently isolated bacteria were E. coli (n = 29; 28.16%), Acinetobacter baumannii (n = 15; 14.56%), and K. pneumoniae (n = 13; 12.26%). Also, the rate of multidrug-resistant (MDR) isolates was 58.25% (60/103). Based on phenotypic confirmation tests, 32 (76.19%) isolates of E. coli and K. pneumoniae produced ESBLs, and 6 (14.28%) isolates were identified as CRE producers. PCR showed the high prevalence of the bla(CTX-M) (n = 29; 90.62%) in ESBL genes. In addition, bla(NDM) was detected in 4 (66.66%), bla(OXA-23) in 3 (50%), and bla(OXA-48) gene in 1 (16.66%) isolates. The bla(VIM), bla(KPC), and bla(IMP) genes were not detected in any of the isolates. CONCLUSION: The Gram-negative bacteria E. coli, A. baumannii, and K. pneumoniae with high resistance levels were the most common bacteria causing NIs in the ICU. This study for the first time identified bla(OXA-11), bla(OXA-23), and bla(NDM-1) genes in E. coli and K. pneumoniae in Ilam city of Iran.202337155016
1479190.9893BioFire FilmArray BCID2 versus VITEK-2 System in Determining Microbial Etiology and Antibiotic-Resistant Genes of Pathogens Recovered from Central Line-Associated Bloodstream Infections. Central line-associated bloodstream infection (CLABSI) is among the most serious hospital acquired infections. Therefore, the rapid detection of the causative microorganism is of crucial importance to allow for the appropriate antimicrobial therapy. In the present study, we analyzed the clinical performance of the BioFire FilmArray Blood Culture Identification 2 (BCID2) panel in the identification of 33 microbial species and 10 antibiotic resistance genes in comparison to the VITEK-2 system. A total of 104 blood specimens were included. The FilmArray BCID2 results were concordant with the VITEK-2 system in 69/97 specimens (71.1%). Non-concordance was either due to the detection of more pathogens by the FilmArray BCID2 23/28 (82%) or microbial species were misidentified 5/28 (18%). Hence, in comparison to the VITEK-2 system, the FilmArray BCID2 panel showed an overall sensitivity of 75.8% (95% CI, 66-83%) and an overall specificity of 98% (95% CI, 97-98.8%) in detecting microbial species. For the resistance genes, the FilmArray BCID was able to detect the presence of blaCTX-M gene in 23 Gram-negative isolates, blaNDM and blaOXA-48- like genes in 14 and 13 isolates, respectively. The mecA and mecC genes were found in 23 Staphylococcus species, while mecA, mecC and MREJ genes were found in 4 Staphylococcus aureus isolates. The sensitivity and specificity for detecting resistance genes by the FilmArray BCID2 was 90% (95% CI, 81.4-95%) and 99.6% (95% CI, 99-100%), respectively. As concluded, the present study emphasizes the high sensitivity and specificity of the FilmArray BCID2 in the rapid and reliable detection of different bacteria and fungi from positive blood culture bottles, as well as the accurate detection of various antibiotic resistance markers.202236358274