Evaluation of Sepsis Flow Chip for identification of Gram-negative bacilli and detection of antimicrobial resistance genes directly from positive blood cultures. - Related Documents




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223701.0000Evaluation 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
223610.9998Development of a Multiplex PCR Platform for the Rapid Detection of Bacteria, Antibiotic Resistance, and Candida in Human Blood Samples. The diagnosis of bloodstream infections (BSIs) still relies on blood culture (BC), but low turnaround times may hinder the early initiation of an appropriate antimicrobial therapy, thus increasing the risk of infection-related death. We describe a direct and rapid multiplex PCR-based assay capable of detecting and identifying 16 bacterial and four Candida species, as well as three antibiotic-resistance determinants, in uncultured samples. Using whole-blood samples spiked with microorganisms at low densities, we found that the MicrobScan assay had a mean limit of detection of 15.1 ± 3.3 CFU of bacteria/Candida per ml of blood. When applied to positive BC samples, the assay allowed the sensitive and specific detection of BSI pathogens, including bla(KPC)-, mecA-, or vanA/vanB-positive bacteria. We evaluated the assay using prospectively collected blood samples from patients with suspected BSI. The sensitivity and specificity were 86.4 and 97.0%, respectively, among patients with positive BCs for the microorganisms targeted by the assay or patients fulfilling the criteria for infection. The mean times to positive or negative assay results were 5.3 ± 0.2 and 5.1 ± 0.1 h, respectively. Fifteen of 20 patients with MicrobScan assay-positive/BC-negative samples were receiving antimicrobial therapy. In conclusion, the MicrobScan assay is well suited to complement current diagnostic methods for BSIs.201931799215
222620.9998Evaluation of the Microbiological Performance and Potential Clinical Impact of New Rapid Molecular Assays for the Diagnosis of Bloodstream Infections. Bloodstream infection (BSI) is a critical medical emergency associated with a high mortality rate. Rapid and accurate identification of the causative pathogen and the results of antimicrobial susceptibility testing are crucial for initiating appropriate antimicrobial therapy. The aim of this study was to evaluate the performance of a new rapid PCR Molecular Mouse System (MMS) for the identification of Gram-negative bacteria (GNB) and GNB resistance genes directly from a positive blood culture (BC). The validation of these rapid multiplex assays was carried out in a real hospital setting. A total of 80 BSI episodes were included in our study and the results were compared with culture-based methods. BC samples in which GNB had previously been detected microscopically and which originated from different hospital wards were analysed. The MMS GNB identification assay achieved a sensitivity of 98.7% and a specificity of 100% for the covered pathogens. In one BC sample, Klebsiella aerogenes was identified at the family level (Enterobacteriaceae) with MMS. However, in three polymicrobial samples, MMS identified bacteria that were not detected by culture-based methods (Klebsiella pneumoniae, K. aerogenes and Stenotrophomonas maltophilia). MMS also showed excellent overall performance in the detection of GNB resistance markers (100% sensitivity and 100% specificity). The type of extended-spectrum beta-lactamase (ESBL) resistance gene identified correctly with MMS was CTX-M-1/9 (n = 17/20), alone or in combination with SHV-type β-lactamase or with the different types of carbapenemase genes. MMS detected one carbapenemase gene of each type (KPC, NDM and OXA-23) and six OXA-48 genes. In addition, the colistin resistance gene mcr-1 was detected in one positive BC with Escherichia coli (E. coli). The time to result was significantly shorter for MMS than for routine culture methods. A retrospective analysis of the patients' medical records revealed that a change in empirical antimicrobial therapy would have been made in around half of the patients following the MMS results. These results support the use of MMS as a valuable complement to conventional culture methods for more rapid BSI diagnosis and adjustment of empirical therapy.202540142509
223430.9998Clinical 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
223540.9998Nanosphere's Verigene(®) Blood Culture Assay to Detect Multidrug-Resistant Gram-Negative Bacterial Outbreak: A Prospective Study on 79 Hematological Patients in a Country with High Prevalence of Antimicrobial Resistance. Infections are a major cause of morbidity and mortality in hematological patients. We prospectively tested a new molecular assay (Verigene(®)) in 79 consecutive hematological patients, with sepsis by gram-negative bacteria. A total of 82 gram-negative microorganisms were isolated by blood cultures, of which 76 cases were mono-microbial. Considering the bacteria detectable by the system, the concordance with standard blood cultures was 100%. Resistance genes were detected in 20 of the isolates and 100% were concordant with the phenotypic antibiotic resistance. Overall, this new assay correctly identified 66/82 of all the gram-negative pathogens, yielding a general sensitivity of 80.5%, and providing information on genetic antibiotic resistance in a few hours. This new molecular assay could ameliorate patient management, resulting in a more rational use of antibiotics.201934595420
221750.9997MALDI-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
221860.9997Comparison of in-house and commercial real time-PCR based carbapenemase gene detection methods in Enterobacteriaceae and non-fermenting gram-negative bacterial isolates. BACKGROUND: Carbapenemase-producing gram-negative bacteria are increasing globally and have been associated with outbreaks in hospital settings. Thus, the accurate detection of these bacteria in infections is mandatory for administering the adequate therapy and infection control measures. This study aimed to establish and evaluate a multiplex real-time PCR assay for the simultaneous detection of carbapenemase gene variants in gram-negative rods and to compare the performance with a commercial RT-PCR assay (Check-Direct CPE). METHODS: 116 carbapenem-resistant Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii isolates were genotyped for carbapenemase genes by PCR and sequencing. The defined isolates were used for the validation of the in-house RT-PCR by use of designed primer pairs and probes. RESULTS: Among the carbapenem-resistant isolates the genes bla (KPC), bla (VIM), bla (NDM) or bla (OXA) were detected. Both RT-PCR assays detected all bla (KPC), bla (VIM) and bla (NDM) in the isolates. The in-house RT-PCR detected 53 of 67 (79.0%) whereas the commercial assay detected only 29 (43.3%) of the OXA genes. The in-house sufficiently distinguished the most prevalent OXA types (23-like and 48-like) in the melting curve analysis and direct detection of the genes from positive blood culture vials. CONCLUSION: The Check-Direct CPE and the in-house RT-PCR assay detected the carbapenem resistance from solid culture isolates. Moreover, the in-house assay enabled the identification of carbapenemase genes directly from positive blood-culture vials. However, we observed insufficient detection of various OXA genes in both assays. Nevertheless, the in-house RT-PCR detected the majority of the OXA type genes in Enterobacteriaceae and A. baumannii.201728693493
223870.9997Rapid detection of carbapenem resistance among gram-negative organisms directly from positive blood culture bottles. BACKGROUND: Carbapenemase producing gram-negative bacteria (GNB) has become a huge problem in majority of tertiary care centers worldwide. They are associated with very high morbidity and mortality rates, especially when they cause invasive infections. Therefore, rapid detection of these organisms is very important for prompt and adequate antibiotic therapy as well as infection control. The aim of this study was rapid detection of carbapenemase genes and thereby likely carbapenem resistance, 24-48 hours in advance, directly from the positive-flagged blood culture bottles using CHROMagar and Xpert® Carba-R. METHODS: Aspirate from positively flagged blood culture bottles was subjected to differential centrifuge. All gram-negative bacilli on gram stain from the deposit were processed in Xpert® Carba-R and inoculated on CHROMagar. The presence of genes and growth on CHROMagar was compared with carbapenem resistance on VITEK-2 Compact. RESULTS: A total of 119 GNB isolates were processed. One or more of the carbapenemase genes were detected in 80 isolates. On comparison with VITEK-2 result, 92 samples showed concordance for carbapenem resistance 48 hours in advance. There was discordance in 21 isolates with 12 major errors and 09 minor errors. The sensitivity of direct Xpert® Carba-R test for rapid detection of carbapenem resistance, 48 hours in advance, was 81.42%. The sensitivity of direct CHROMagar test for accurate detection of carbapenem resistance, 24 hours in advance, was 92.06%. CONCLUSION: The ability to detect carbapenem resistance with very high accuracy, 48 hours in advance, helps in appropriate antibiotic therapy and implementation of effective infection control practices.202337193528
221080.9997Beyond 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
222090.9997Rapid 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
2233100.9997Assessment of the multiplex PCR-based assay Unyvero pneumonia application for detection of bacterial pathogens and antibiotic resistance genes in children and neonates. BACKGROUND: Pneumonia is a major healthcare problem. Rapid pathogen identification is critical, but often delayed due to the duration of culturing. Early, broad antibacterial therapy might lead to false-negative culture findings and eventually to the development of antibiotic resistances. We aimed to assess the accuracy of the new application Unyvero P50 based on multiplex PCR to detect bacterial pathogens in respiratory specimens from children and neonates. METHODS: In this prospective study, bronchoalveolar lavage fluids, tracheal aspirates, or pleural fluids from neonates and children were analyzed by both traditional culture methods and Unyvero multiplex PCR. RESULTS: We analyzed specimens from 79 patients with a median age of 1.8 (range 0.01-20.1). Overall, Unyvero yielded a sensitivity of 73.1% and a specificity of 97.9% compared to culture methods. Best results were observed for non-fermenting bacteria, for which sensitivity of Unyvero was 90% and specificity 97.3%, while rates were lower for Gram-positive bacteria (46.2 and 93.9%, respectively). For resistance genes, we observed a concordance with antibiogram of 75% for those specimens in which there was a cultural correlate. CONCLUSIONS: Unyvero is a fast and easy-to-use tool that might provide additional information for clinical decision making, especially in neonates and in the setting of nosocomial pneumonia. Sensitivity of the PCR for Gram-positive bacteria and important resistance genes must be improved before this application can be widely recommended.201829086343
2209110.9997Concordance Between Antibiotic Resistance Genes and Susceptibility in Symptomatic Urinary Tract Infections. PURPOSE: Studies have shown that multiple genes influence antibiotic susceptibility, but the relationship between genotypic and phenotypic antibiotic susceptibility is unclear. We sought to analyze the concordance between the presence of antibiotic resistance (ABR) genes and antibiotic susceptibility results in urine samples collected from patients with symptomatic urinary tract infection (UTI). PATIENTS AND METHODS: Urine samples were collected from patients presenting to 37 geographically disparate urology clinics across the United States from July 2018 to February 2019. Multiplex polymerase chain reaction was used to detect 27 ABR genes. In samples containing at least one culturable organism at a concentration of ≥ 10(4) cells per mL, pooled antibiotic susceptibility testing (P-AST), which involves simultaneous growing all detected bacteria together in the presence of antibiotic and then measure susceptibility, was performed against 14 antibiotics. The concordance rate between the ABR genes and the P-AST results was generated for the overall group. The concordance rates for each antibiotic between monomicrobial and polymicrobial infection were compared using chi-square test. RESULTS: Results from ABR gene detection and P-AST of urine samples from 1155 patients were included in the concordance analysis. Overall, there was a 60% concordance between the presence or absence of ABR genes and corresponding antimicrobial susceptibility with a range of 49-78% across antibiotic classes. Vancomycin, meropenem, and piperacillin/tazobactam showed significantly lower concordance rates in polymicrobial infections than in monomicrobial infections. CONCLUSION: Given the 40% discordance rate, the detection of ABR genes alone may not provide reliable data to make informed clinical decisions in UTI management. However, when used in conjunction with susceptibility testing, ABR gene data can offer valuable clinical information for antibiotic stewardship.202134447256
2230120.9997Rapid detection of gram-negative antimicrobial resistance determinants directly from positive blood culture broths using a multiplex PCR system. Currently available rapid blood culture diagnostics detect few gram-negative resistance determinants, limiting their clinical utility. We prospectively evaluated the prototype BIOFIRE FILMARRAY Antimicrobial Resistance (AMR) Panel, a rapid multiplex PCR test that detects 31 AMR genes, on residual positive blood culture broths from patients with gram-negative bacteremia due to five target organisms at a New York City hospital. Predicted antimicrobial resistance based on the AMR Panel was compared to results from broth microdilution testing of bloodstream isolates recovered in culture. A simulated stewardship study assessed opportunities for the optimization of therapy if the AMR Panel results had been available for patient care in real time. We enrolled 148 patients with gram-negative bacteremia (Escherichia coli, n = 75; Klebsiella pneumoniae, n = 44; Pseudomonas aeruginosa, n = 17; Enterobacter cloacae complex, n = 9; and Acinetobacter baumannii, n = 3). The sensitivity of the AMR Panel for predicting antimicrobial resistance was ≥90% for 10/14 antimicrobial agents in E. coli and for 10/16 agents in K. pneumoniae. Specificity was ≥90% for 15/17 agents in E. coli and for all 16 agents in K. pneumoniae. Performance for other organisms was poor. For E. coli or K. pneumoniae bacteremia, use of the AMR Panel could have led to earlier escalation or de-escalation of β-lactam therapy in a majority of patients compared to what actually occurred. This study demonstrates that a rapid multiplex PCR test with a large menu of AMR genes can be applied to positive blood culture broths to rapidly predict resistance to frontline antimicrobial agents in patients with E. coli or K. pneumoniae bacteremia.IMPORTANCEPatients with gram-negative bacteremia require urgent treatment with antimicrobial agents that are effective against their infecting pathogen. However, conventional laboratory work-up of blood cultures takes days to yield results, and during this time, patients may receive ineffective therapies. We evaluated the prototype BIOFIRE FILMARRAY AMR Panel, an assay that detects 31 genes in gram-negative bacteria that confer resistance to β-lactams, fluoroquinolones, and aminoglycosides in approximately 1 hour, directly from positive blood culture broths, and compared these results to antimicrobial susceptibility testing of isolates recovered in culture. We found that the AMR Panel accurately predicted resistance in Escherichia coli and Klebsiella pneumoniae to most antimicrobials. Moreover, if results from this assay had been used for patient care, there would have been opportunities to optimize antimicrobial prescribing more quickly than using conventional methods. These data demonstrate how novel molecular assays could optimize care for patients with E. coli and K. pneumoniae bacteremia.202541117625
2308130.9997Trends of Antibiotic Resistance in Multidrug-Resistant Pathogens Isolated from Blood Cultures in a Four-Year Period. BACKGROUND: Multidrug-resistant organisms cause serious infections with significant morbidity and mortality in the worldwide. These organisms have been identified as urgent and serious threats by CDC. The aim of this study was to determine the prevalence and changes of antibiotic resistance of multidrug-resistant pathogens isolated from blood cultures over a four-year period in a tertiary-care hospital. METHODS: Blood cultures were incubated in a blood culture system. Positive signalling blood cultures were subcultured on 5% sheep-blood agar. Identification of isolated bacteria was performed using conventional or automated identification systems. Antibiotic susceptibility tests were performed by disc diffusion and/or gradient test methods, if necessary, by automated systems. The CLSI guidelines were used for interpretation of antibiotic susceptibility testing of bacteria. RESULTS: The most frequently isolated Gram-negative bacteria was Escherichia coli (33.4%) followed by Klebsiella pneumoniae (21.5%). ESBL positivity was 47% for E. coli, 66% for K. pneumoniae. Among E. coli, K. pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii isolates, carbapenem resistance was 4%, 41%, 37%, and 62%, respectively. Carbapenem resistance of K. pneumoniae isolates has increased from 25% to 57% over the years, and the highest rate (57%) occured during the pandemic period. It is noteworthy that the aminoglycoside resistance in E. coli isolates gradually increased from 2017 to 2021. The rate of methicillin-resistant S. aureus (MRSA) was found to be 35.5%. CONCLUSIONS: Increased carbapenem resistance in K. pneumoniae and A. baumannii isolates is noteworthy, but carbapenem resistance in P. aeruginosa decreased. It is of great importance for each hospital to monitor the increase in resistance in clinically important bacteria, especially isolated from invasive samples, in order to take the necessary precautions in a timely manner. Future studies involving clinical data of patients and bacterial resistance genes are warranted.202337307126
2205140.9997Five-year period evaluation of isolated agents and their resistance profiles in intensive care unit patients with malignancy. INTRODUCTION: Patients treated in the intensive care unit (ICU) are usually patients who deteriorated health condition and could have longer hospital stay compared to other patients. Hospital infections are more common in ICU patients. The aim of this study was to evaluate the bacteria and treatment resistance profiles isolated from clinical specimens sent for hospital infections in ICU patients between January 1, 2014 and December 31, 2018. METHODOLOGY: Bacteria isolated from various clinical samples sent for hospital infections in hospitalized patients in the Anesthesia and Reanimation Intensive Care Unit were retrospectively analyzed. RESULTS: Culture positivity was detected in 547 of the sent clinical samples. Eighty Gram-positive bacteria, 389 Gram-negative bacteria and 78 fungi infection were identified in a total of 547 positive cultures. In Gram-positive bacteria, 4 MRSA, 6 VRE and 30 MRCoNS were identified as resistant strains. In Gram-negative bacteria, Acinetobacter spp. was the most culture positive strain with the number of 223. Carbapenem resistance was found in 258 of the Gram-negative bacteria and ESBL positivity was found in 44 of the Gram-negative bacteria strains. CONCLUSIONS: Gram-negative bacteria were the most frequently isolated strain in samples. Recently, colistin resistance has been increasing in Acinetobacter spp. and the increase in carbapenemase enzyme in Escherichia coli, Pseudomonas and Klebsiella species has increased resistance to carbapenems. Knowing the microorganisms that grow in ICUs and their antibiotic resistance patterns may help to prevent contamination of resistant microorganisms by both appropriate empirical antibiotic treatment and more isolation as well as general hygiene standard precautions.202032903237
1676150.9997Evaluation of carbapenem resistance using phenotypic and genotypic techniques in Enterobacteriaceae isolates. BACKGROUND: Bacterial resistance to antibiotics is increasing worldwide. Antibiotic-resistant strains can lead to serious problems regarding treatment of infection. Carbapenem antibiotics are the final treatment option for infections caused by serious and life-threatening multidrug-resistant gram-negative bacteria. Therefore, an understanding of carbapenem resistance is important for infection control. In the study described herein, the phenotypic and genotypic features of carbapenem-resistant Enterobacteriaceae strains isolated in our hospital were evaluated. METHODS: In total, 43 carbapenem-resistant strains were included in this study. Sensitivity to antibiotics was determined using the VITEK(®)2 system. The modified Hodge test (MHT) and metallo-β-lactamase (MBL) antimicrobial gradient test were performed for phenotypic identification. Resistance genes IMP, VIM, KPC, NDM-1, and OXA-48 were amplified by multiplex PCR. RESULTS: The OXA-48 gene was detected in seven strains, and the NDM-1 gene in one strain. No resistance genes were detected in the remainder of strains. A significant correlation was observed between the MHT test and OXA-48 positivity, and between the MBL antimicrobial gradient test and positivity for resistance genes (p < 0.05). CONCLUSION: The finding of one NDM-1-positive isolate in this study indicates that carbapenem resistance is spreading in Turkey. Carbapenem resistance spreads rapidly and causes challenges in treatment, and results in high mortality/morbidity rates. Therefore, is necessary to determine carbapenem resistance in Enterobacteriaceae isolates and to take essential infection control precautions to avoid spread of this resistance.201526444537
2225160.9997Evaluation of the DNA microarray "AMR Direct Flow Chip Kit" for detection of antimicrobial resistance genes from Gram-positive and Gram-negative bacterial isolated colonies. INTRODUCTION: The AMR Direct Flow Chip assay allows the simultaneous detection of a large variety of antibiotic resistance genetic markers. To assess this kit's performance, we use isolated colonies as starting material. The assay has been approved by the European Economic Area as a suitable device for in vitro diagnosis (CE IVD) using clinical specimens. METHODS: A total of 210 bacterial isolates harbouring either one or more antimicrobial resistance genes including plasmid-encoded extended-spectrum β-lactamases (SHV, CTX-M) and carbapenemases (GES, SME, KPC, NMC/IMI, SIM, GIM, SPM, NDM, VIM, IMP, and OXA), mecA, vanA and vanB, and 30 controls were included. RESULTS: The assay displayed a sensitivity and specificity of 100% for all target genes included in the array. CONCLUSION: The AMR Direct Flow Chip Kit is an accurate assay for detecting genes which commonly confer resistance to β-lactams and vancomycin from isolated colonies in culture of Gram-positive and Gram-negative bacteria.201930857832
1490170.9996Rapid 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
2252180.9996Antimicrobial resistance of 3 types of gram-negative bacteria isolated from hospital surfaces and the hands of health care workers. BACKGROUND: There has been an increased focus in recent years on antimicrobial resistance of bacteria isolated from clinical samples. However, resistance of bacteria from hospital environments has been less frequently investigated. METHODS: According to hygienic standard for disinfection in hospitals, samples were collected from hospital inanimate surfaces and the hands of health care workers after daily cleaning. An automatic microorganism analyzer was used to identify bacteria and test for antimicrobial susceptibility. Polymerase chain reaction was used to detect antimicrobial resistance genes. RESULTS: The detection rate of bacteria in general wards was significantly higher than that in intensive care units. The isolates were predominantly gram-negative (GN) bacteria, with Pseudomonas aeruginosa, Enterobacter cloacae, and Klebsiella pneumoniae being the most common. P aeruginosa isolates from other surfaces were much higher than those from medical instruments. E cloacae was isolated more frequently from the hands of other staff than medical staff. Most P aeruginosa and K pneumoniae were resistant to sulfonamides and β-lactam antimicrobials. Only 1 strain of P aeruginosa and 1 strain of K pneumoniae showed multiple antimicrobials resistance. CONCLUSIONS: The GN bacteria isolated from hospital environments demonstrate variable resistance to antimicrobials.201728780198
2219190.9996Development 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