Prospective observational pilot study of the T2Resistance panel in the T2Dx system for detection of resistance genes in bacterial bloodstream infections. - Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
148001.0000Prospective observational pilot study of the T2Resistance panel in the T2Dx system for detection of resistance genes in bacterial bloodstream infections. Early initiation of antimicrobial therapy targeting resistant bacterial pathogens causing sepsis and bloodstream infections (BSIs) is critical for a successful outcome. The T2Resistance Panel (T2R) detects the following resistance genes within organisms that commonly cause BSIs directly from patient blood samples: bla(KPC), bla(CTXM-14/15), bla(NDM)/bla(/IMP)/bla(VIM), bla(AmpC), bla(OXA), vanA, vanB, and mecA/mecC. We conducted a prospective study in two major medical centers for the detection of circulating resistance genes by T2R in patients with BSIs. T2R reports were compared to antimicrobial susceptibility testing (AST), phenotypic identification, and standard molecular detection assays. Among 59 enrolled patients, 25 resistance genes were identified: bla(KPC) (n = 10), bla(NDM)/bla(/IMP)/bla(VIM) (n = 5), bla(CTXM-14/15) (n = 4), bla(AmpC) (n = 2), and mecA/mecC (n = 4). Median time-to-positive-T2R in both hospitals was 4.4 hours [interquartile range (IQR): 3.65-4.97 hours] in comparison to that for positive blood cultures with final reporting of AST of 58.34 h (IQR: 45.51-111.2 hours; P < 0.0001). The sensitivity of T2R to detect the following genes in comparison to AST was 100% for bla(CTXM-14/15), bla(NDM)/bla(/)(IMP)/bla(VIM), bla(AmpC), mecA/mecC and 87.5% for bla(KPC). When monitored for the impact of significant antimicrobial changes, there were 32 events of discontinuation of unnecessary antibiotics and 17 events of escalation of antibiotics, including initiation of ceftazidime/avibactam in six patients in response to positive T2R results for bla(KPC). In summary, T2R markers were highly sensitive for the detection of drug resistance genes in patients with bacterial BSIs, when compared with standard molecular resistance detection systems and phenotypic identification assays while significantly reducing by approximately 90% the time to detection of resistance compared to standard methodology and impacting clinical decisions for antimicrobial therapy. IMPORTANCE: This is the first reported study to our knowledge to identify key bacterial resistance genes directly from the bloodstream within 3 to 5 hours in patients with bloodstream infections and sepsis. The study further demonstrated a direct effect in modifying initial empirical antibacterial therapy in response to T2R signal to treat resistant bacteria causing bloodstream infections and sepsis.202438456690
221010.9995Beyond Culture: Real-Time PCR Performance in Detecting Causative Pathogens and Key Antibiotic Resistance Genes in Hospital-Acquired Pneumonia. Introduction: The rise in hospital-acquired pneumonia (HAP) due to antibiotic-resistant bacteria is increasing morbidity, mortality, and inappropriate empirical antibiotic use. This prospective research aimed to evaluate the performance of a real-time polymerase chain reaction (PCR) assay for detecting causative microorganisms and antibiotic-resistance genes from respiratory specimens compared to traditional methods. Additionally, we aimed to determine the molecular epidemiology of antibiotic resistance genes among HAP patients at The University of Jordan hospital. Methods: Lower respiratory tract samples were collected from HAP patients, including those with ventilator-associated pneumonia (VAP), between May 2024 and October 2024. Clinical data from the medical files were used to collect and analyze demographic and clinical information, including clinical outcomes. Real-time PCR was run to detect causative microbes and antibiotic resistance genes. Results: Among 83 HAP patients (median age 63, 61.45% male), 48.15% died. Culture identified Klebsiella (25.53%), Acinetobacter (22.34%), and Candida (24.47%) as the most common pathogens, while qPCR showed higher detection rates, including for A. baumannii (62.20%, p = 0.02) and K. pneumoniae (45.12%, p < 0.001). Carbapenem resistance was high; A. baumannii showed 100% resistance to most antibiotics except colistin (92.31%). The resistance genes ndm (60%) and oxa-48 (58.46%) were frequently detected and significantly associated with phenotypic resistance (p < 0.001). The qPCR identified resistance genes in all carbapenem-resistant cases. No gene significantly predicted mortality. Conclusions: Real-time PCR diagnostic technique combined with epidemiology of antibiotic resistance genes data may be a rapid and effective tool to improve HAP management. Large, multicenter studies are needed in the future to validate the performance of real-time PCR in HAP diagnosis, and appropriate management is also required.202541009915
147920.9995BioFire 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
147830.9995Multicenter 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
149040.9995Rapid detection of Gram-negative bacteria and their drug resistance genes from positive blood cultures using an automated microarray assay. We evaluated the performance of the Verigene Gram-negative blood culture (BC-GN) assay (CE-IVD version) for identification of Gram-negative (GN) bacteria and detection of resistance genes. A total of 163 GN organisms (72 characterized strains and 91 clinical isolates from 86 patients) were tested; among the clinical isolates, 86 (94.5%) isolates were included in the BC-GN panel. For identification, the agreement was 98.6% (146/148, 95% confidence interval [CI], 92.1-100) and 70% (7/10, 95% CI, 53.5-100) for monomicrobial and polymicrobial cultures, respectively. Of the 48 resistance genes harbored by 43 characterized strains, all were correctly detected. Of the 19 clinical isolates harboring resistance genes, 1 CTX-M-producing Escherichia coli isolated in polymicrobial culture was not detected. Overall, BC-GN assay provides acceptable accuracy for rapid identification of Gram-negative bacteria and detection of resistance genes, compared with routine laboratory methods despite that it has limitations in the number of genus/species and resistance gene included in the panel and it shows lower sensitivity in polymicrobial cultures.201525591999
149150.9995Evaluation of an expanded antibiotic resistance gene panel on prediction of antimicrobial susceptibility results for Gram-negative bacteria in blood cultures. The QIAstat-Dx BCID Panels (RUO) ("QIAstat," QIAGEN, Hilden, Germany) for identification of 13 Gram-negative bacteria and 18 antimicrobial resistance (AMR) gene groups was evaluated. The study was conducted in two phases; in phase 1, analytical performance was evaluated against 154 challenge isolates against whole genome sequencing data. In this phase, sensitivity and specificity of organism identification calls were 153/154 (99.3%) and 1,748/1,749 (99.8%), respectively. For AMR genes, sensitivity was 434/435 (99.8%) and specificity was 2,334/2,337 (99.9%). One false-negative bla(IMP), one false-positive bla(CTX-M), and two false-positive aac-6'-lb detections were noted in this challenge set of organisms. In phase 2, 101 clinical blood culture isolates of Gram-negative rods were evaluated by the multiplexed PCR versus reference broth microdilution, for the ability of identification combined with AMR genes to predict final susceptibility results. Negative predictive values were 92.8% for ampicillin resistance (100% for Escherichia coli), 93.4% for ceftriaxone, 97.4% for ceftazidime, and 98.7% for cefepime. In constrast, negative predictive values for current standard of care (identification plus detection of bla(CTX-M)) ranged from 56.5% to 88.8%. This study demonstrated additive value of additional beta-lactamase genes for bacteria isolated from blood cultures. IMPORTANCE: Prediction of Gram-negative bacteria resistance through detection of resistance genes is complex. This study evaluated a novel, direct-from-blood or bacterial isolate multiplexed PCR for the detection of 17 resistance genes, and evaluated the prediction of antimicrobial susceptibility.202439297627
211360.9995The 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
222070.9995Rapid detection and molecular survey of blaVIM, blaIMP and blaNDM genes among clinical isolates of Acinetobacter baumannii using new multiplex real-time PCR and melting curve analysis. BACKGROUND: Acinetobacter baumannii is a cosmopolitan bacterium that is frequently reported from hospitalized patients, especially those patients who admitted in the intensive care unit. Recently, multiplex real-time PCR has been introduced for rapid detection of the resistance genes in clinical isolates of bacteria. The current study aimed to develop and evaluate multiplex real-time PCR to detect common resistance genes among clinical isolates of A. baumannii. RESULTS: Multiplex real-time PCR based on melting curve analysis showed different T(m) corresponding to the amplified fragment consisted of 83.5 °C, 93.3 °C and 89.3 °C for blaIMP, blaVIM and blaNDM, respectively. Results of multiplex real-time PCR showed that the prevalence of blaIMP, blaVIM and blaNDM among the clinical isolates of A. baumannii were 5/128(3.9%), 9/128(7.03%) and 0/128(0%), respectively. Multiplex real-time PCR was able to simultaneously identify the resistance genes, while showed 100% concordance with the results of conventional PCR. CONCLUSIONS: The current study showed that blaVIM, was the most prevalent MBL gene among the clinical isolates of A. baumannii while no amplification of blaNDM was seen. Multiplex real-time PCR can be sensitive and reliable technique for rapid detection of resistance genes in clinical isolates.201931182026
223480.9995Clinical relevance of molecular identification of microorganisms and detection of antimicrobial resistance genes in bloodstream infections of paediatric cancer patients. BACKGROUND: Bloodstream infections (BSIs) are the major cause of mortality in cancer patients. Molecular techniques are used for rapid diagnosis of BSI, allowing early therapy and improving survival. We aimed to establish whether real-time quantitative polymerase chain reaction (qPCR) could improve early diagnosis and therapy in paediatric cancer patients, and describe the predominant pathogens of BSI and their antimicrobial susceptibility. METHODS: Blood samples were processed by the BACTEC system and microbial identification and susceptibility tests were performed by the Phoenix system. All samples were screened by multiplex 16 s rDNA qPCR. Seventeen species were evaluated using sex-specific TaqMan probes and resistance genes blaSHV, blaTEM, blaCTX, blaKPC, blaIMP, blaSPM, blaVIM, vanA, vanB and mecA were screened by SYBR Green reactions. Therapeutic efficacy was evaluated at the time of positive blood culture and at final phenotypic identification and antimicrobial susceptibility results. RESULTS: We analyzed 69 episodes of BSI from 64 patients. Gram-positive bacteria were identified in 61 % of the samples, Gram-negative bacteria in 32 % and fungi in 7 %. There was 78.2 % of agreement between the phenotypic and molecular methods in final species identification. The mecA gene was detected in 81.4 % of Staphylococcus spp., and 91.6 % were concordant with the phenotypic method. Detection of vanA gene was 100 % concordant. The concordance for Gram-negative susceptibilities was 71.4 % for Enterobacteriaceae and 50 % for Pseudomonas aeruginosa. Therapy was more frequently inadequate in patients who died, and the molecular test was concordant with the phenotypic susceptibility test in 50 %. CONCLUSIONS: qPCR has potential indication for early identification of pathogens and antimicrobial resistance genes from BSI in paediatric cancer patients and may improve antimicrobial therapy.201627585633
221990.9994Development and validation of a multiplex TaqMan real-time PCR for rapid detection of genes encoding four types of class D carbapenemase in Acinetobacter baumannii. A multiplex TaqMan real-time PCR to detect carbapenem-hydrolysing class D β-lactamases (bla(OXA-23)-like, bla(OXA-24/40)-like, bla(OXA-51)-like and bla(OXA-58)-like genes) was developed and evaluated for early detection of imipenem (IMP) resistance in clinically significant Acinetobacter baumannii isolates. Well-characterized strains of A. baumannii were used as positive controls and non-Acinetobacter strains were used to assess specificity. Analytical sensitivity was quantified by comparison with the number of bacterial c.f.u. Forty of 46 (87 %) clinically significant and IMP-resistant A. baumannii isolates were positive for the bla(OXA-23)-like gene, and one isolate (2 %) was positive for the bla(OXA-58)-like gene. The bla(OXA-24/40)-like gene was not detected in any of the 46 IMP-resistant strains and the bla(OXA-51)-like gene was identified in both IMP-resistant and non-resistant A. baumannii. All 11 non-Acinetobacter bacteria produced a negative result for each of the four bla(OXA) genes. This assay was able to detect as few as 10 c.f.u. per assay. This real-time PCR method demonstrated rapid detection of OXA-like carbapenem resistance in A. baumannii in comparison with phenotypic susceptibility testing methodology. This method could be adapted to a multiplexed single reaction for rapid detection of genes associated with carbapenem resistance in A. baumannii and potentially other clinically significant multidrug-resistant Gram-negative bacteria.201222878252
2124100.9994Evaluation 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
1489110.9994Direct detection of mecA, bla(SHV) , bla(CTX)(-M) , bla(TEM) and bla(OXA) genes from positive blood culture bottles by multiplex-touchdown PCR assay. Methicillin-resistant staphylococci (MRS) and ESBL(Extended-Spectrum β-Lactamase)-producing bacteria are the most important resistant pathogens in sepsis. In this study, a new multiplex-touchdown PCR method (MT-PCR) was developed to detect rapidly and simultaneously the presence of mecA, bla(SHV) , bla(CTX)(-M) , bla(TEM) and bla(OXA) genes from positive blood culture bottles. The technique showed a sensitivity of 10(3 ) CFU ml(-1) for mecA detection and of 10(2)  CFU ml(-1) for other genes, and 100% specificity in the detection of all genes. All genes were detected in the spiked blood culture bottles artificially contaminated with reference strains. Three methicillin-resistant S. aureus (MRSA), two methicillin-resistant S. epidermidis (MRSE) and 32 ESBL-producing bacteria, were isolated from the clinical blood culture specimens in 48 h by standard microbiological procedures. The corresponding genes were detected directly in the three MRSA, two MRSE and 29 ESBL-producing bacteria from the clinical blood culture specimens in 4 h by MT-PCR assay. None of the bla(SHV) , bla(CTX)(-M) , bla(TEM) and bla(OXA) genes were detected in three other bottles with ESBL-producing bacteria because of other ESBL genotypes in the pathogens. Likewise, all bottles proven negative by culture remained negative by PCR. The proposed method was rapid, sensitive and specific, and was able to directly detect the genes of MRS and ESBL-producing bacteria from the blood culture bottles. SIGNIFICANCE AND IMPACT OF THE STUDY: Many studies on the development of PCR for the detection of resistance genes have already been published, including multiplex PCR methods. However, cross-amplification reactions can be a major concern in multiplex PCR methods. In this study, we developed a highly sensitive and specific multiplex-touchdown PCR assay for simultaneous detection of mecA, bla(SHV) , bla(CTX)(-M) , bla(TEM) and bla(OXA) genes from positive blood culture bottles, cross-amplification was absent and false-positive results were not obtained.201727699804
2237120.9994Evaluation of Sepsis Flow Chip for identification of Gram-negative bacilli and detection of antimicrobial resistance genes directly from positive blood cultures. Blood stream infections are serious conditions associated with high morbi-mortality. In this study, the new Sepsis Flow Chip (SFC) assay for identification of Gram-negative bacteria and their antimicrobial resistance genes was evaluated in positive blood cultures (BCs). SFC is a microarray with a broad panel comprising the most frequent causative agents of sepsis and antimicrobial resistance genes associated with them. A total of 100 prospective BCs, positive for Gram-negative bacilli, were assessed in the routine of the clinical microbiology laboratory and also applying the SFC assay. Moreover, 19 BCs spiked with well-characterized enterobacterial isolates, harboring antimicrobial resistance genes, were analyzed by the latter. Among the monomicrobial BCs (90), the concordance between SFC identification and the reference method was 94.4%; however, it achieved 100% when SFC was combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry after 4-h incubation. Regarding polymicrobial BCs (10), 15 out of the 22 bacteria present (68.2%) were correctly identified, including all contained in 50% of the cultures. With regard to antimicrobial resistance genes, 98.8%, 98.9%, and 99% concordance was obtained for bla(CTX-M), bla(OXA-48), and bla(VIM), respectively, in comparison with polymerase chain reaction amplification. SFC assay gives results in only 4 h and showed a high concordance rate with the reference method. Although further evaluation studies are necessary, SFC assay implementation, together with antimicrobial stewardship programs, could contribute to improve the therapeutic approaches and to reduce the morbi-mortality, length of hospital stay, and healthcare-associated costs in patients with sepsis.201829551362
2217130.9994MALDI-TOF MS based carbapenemase detection from culture isolates and from positive blood culture vials. BACKGROUND: Antibiotic resistance in bacteria leads to massive health problems. Incidence of carbapenem and multidrug resistance in Gram-negative bacteria are increasing globally and turn out to be a very urgent challenge in health care. Resistant bacteria play an important clinical role during hospital outbreaks as well as in sepsis. Rapid diagnostic tests are necessary to provide immediate information for antimicrobial treatment and infection control measures. METHODS: Our mass spectrometry-based assay was validated with 63 carbapenemase-producing Gram-negative bacterial isolates, and 35 carbapenem-resistant Gram-negative species with no carbapenemase production. These were analyzed from solid culture media and positive blood culture vials. After 4 h of incubation the carbapenemase products were analyzed with the MALDI-TOF MS. All the isolates were genotyped for carbapenemase genes by PCR and sequencing. RESULTS: For culture isolates the concordance of hydrolysis assay to genetic results was 98 % for OXA variants, KPC, VIM, IMP, GIM, and NDM. In contrast, only 14 of 29 Acinetobacter baumannii isolates carrying the OXA and NDM genes could be identified from blood culture. However, from blood culture vials our method allowed the detection of carbapenemases in 98 % of Pseudomonas and Enterobacteriaceae isolates harboring different genes. CONCLUSIONS: This MALDI-TOF MS-based assay permitted the detection of carbapenemases either from solid culture media (98-100 %) or blood culture vials (96 %) for all non-A. baumannii isolates within 4 h. In case of A. baumannii isolates the assay was highly sensitive for the detection of carbapenemases directly from solid culture media.201626839024
2115140.9994Assessment 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
924150.9994Screening 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
2196160.9994Antibiotic 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
2200170.9994Bloodstream infections and antibiotic resistance at a regional hospital, Colombia, 2019-2021. OBJECTIVES: To assess antibiotic susceptibility of World Health Organization (WHO) priority bacteria (Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Salmonella spp., Staphylococcus aureus, and Streptococcus pneumoniae) in blood cultures at the Orinoquía regional hospital in Colombia. METHODS: This was cross-sectional study using routine laboratory data for the period 2019-2021. Data on blood samples from patients suspected of a bloodstream infection were examined. We determined: the total number of blood cultures done and the proportion with culture yield; the characteristics of patients with priority bacteria; and the type of bacteria isolated and antibiotic resistance patterns. RESULTS: Of 25 469 blood cultures done, 1628 (6%) yielded bacteria; 774 (48%) of these bacteria were WHO priority pathogens. Most of the priority bacteria isolated (558; 72%) were gram-negative and 216 (28%) were gram-positive organisms. Most patients with priority bacteria (666; 86%) were hospitalized in wards other than the intensive care unit, 427 (55%) were male, and 321 (42%) were ≥ 60 years of age. Of the 216 gram-positive bacteria isolated, 205 (95%) were Staphylococcus aureus. Of the 558 gram-negative priority bacteria isolated, the three most common were Escherichia coli (34%), Klebsiella pneumoniae (28%), and Acinetobacter baumannii (20%). The highest resistance of Staphylococcus aureus was to oxacillin (41%). For gram-negative bacteria, resistance to antibiotics ranged from 4% (amikacin) to 72% (ampicillin). CONCLUSIONS: Bacterial yield from blood cultures was low and could be improved. WHO priority bacteria were found in all hospital wards. This calls for rigorous infection prevention and control standards and continued surveillance of antibiotic resistance.202337082533
2311180.9994Serious antimicrobial resistance status of pathogens causing hospital-acquired lower respiratory tract infections in North China. Antimicrobial resistance patterns of pathogens causing hospital-acquired lower respiratory tract infections (LRTIs) in Shandong Province, China were investigated using data collected from January 2002 to December 2006. A total of 10 337 isolates were characterized in sputum samples from 39 920 LRTI patients: 68.72% were Gram-negative bacteria, 20.65% were Gram-positive bacteria, and 10.62% were fungi. Organisms most frequently isolated were: Pseudomonas aeruginosa (16.88%), Klebsiella pneumoniae (10.80%), Escherichia coli (10.71%), fungi (10.62%), Staphylococcus aureus (9.68%) and Acinetobacter baumannii (9.03%). Imipenem was the most effective antibiotic against Gram-negative bacteria. Most Gram-positive bacteria were susceptible to vancomycin. Susceptibility to cephalosporins was not optimal and resistance to fluoroquinolones was high. Resistance of Gram-negative bacteria showed a rapid increase over the study period, while resistance of Gram-positive bacteria remained relatively stable. The emergence of resistance to commonly prescribed antimicrobial agents used against LRTI pathogens has compounded the problem of using empirical therapy and created selective pressure on physicians to use certain antibiotics.200919589276
2112190.9994Multidrug-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