Evaluation of two rapid phenotypical tests-Alifax rapid AST colistin test and Rapid Polymyxin NP test-for detection of colistin resistance in Enterobacterales.
Ontology highlight
ABSTRACT:
SUBMITTER: Germ J
PROVIDER: S-EPMC8295142 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:A biochemical test (NitroSpeed-Carba NP test) was developed to identify carbapenemase production in Enterobacterales and to discriminate between the different types of clinically significant carbapenemases (Ambler classes A, B, and D). It is based on two main features, namely, the hydrolysis by all β-lactamases, including carbapenemases of the nitrocefin substrate, and the capacity of ertapenem to prevent this hydrolysis for all β-lactamases except carbapenemases. Specific carbapenemase inhibitors of class A (avibactam, vaborbactam), class B (dipicolinic acid), and class D (avibactam) were used to inhibit the nitrocefin hydrolysis and to allow the identification of the carbapenemase types with a turnaround time of ca. 30 min. The test was evaluated with a collection of 248 clinical enterobacterial isolates, including 148 carbapenemase producers and 100 non-carbapenemase producers. Its overall sensitivity and specificity were 100% and 97%, respectively, including detection of all types of OXA-48-like carbapenemases. For the detection of the carbapenemase type, including strains that produce double carbapenemases, the sensitivity was 100%, 97%, and 100% for the detection of classes A, B, and D, respectively. This easy-to-implement test may contribute to optimization of the choice of the β-lactam/β-lactamase inhibitor combinations for treating infection due to carbapenemase producers.
| S-EPMC7448648 | biostudies-literature
Project description:Polymyxins are important therapeutic options for treating infections, mainly those caused by carbapenem-resistant Klebsiella pneumoniae. Specific chemical characteristics of polymyxins make it difficult to perform antimicrobial susceptibility testing, especially within the clinical laboratory. Here we aimed to evaluate the performance of three phenotypic methods: Rapid NP Polymyxin Test, ColiSpot test and the SuperPolymyxin medium. To accomplish this, 170 non-duplicate clinical K. pneumoniae isolates were analysed (123 colistin-resistant and 47 susceptible). The sensitivity and specificity obtained for Rapid Polymyxin NP Test, Colispot and SuperPolymyxin medium were, respectively, 90% and 94%, 74% and 100%, and 82% and 85%. Very major errors occurred more frequently in low-level colistin-resistant isolates (MICs 4 and 8 ?g/mL). Rapid Polymyxin NP proved to be a method capable of identifying colistin-resistant strains in acceptable categorical agreement. However, major errors and very major errors of this method were considered unacceptable for colistin-resistance screening. Although the Colispot test is promising and easy to perform and interpret, the results did not reproduce well in the isolates tested. The colistin-containing selective medium (SuperPolymyxin) showed limitations, including quantification of mucoid colonies and poor stability. Nevertheless, Colispot and SuperPolymyxin medium methods did not present acceptable sensitivity, specificity and categorical agreement. It is essential to use analytical tools that faithfully reproduce bacterial resistance in vitro, especially in last-line drugs, such as polymyxins, when misinterpretation of a test can result in therapeutic ineffectiveness.
| S-EPMC7334411 | biostudies-literature
Project description:Introduction. Carbapenemase-producing Enterobacterales (CPE) are an increasing threat to global health. Fast detection is crucial for patient management and outbreak control.Hypothesis/Gap statement. Recently, a new commercial colorimetric test, CARBA PAcE, was released that has not yet been scientifically evaluated.Aim. Our goals were to evaluate the performance of CARBA PAcE using a large variety of different CPE.Methodology. CARBA PAcE was challenged with 107 molecularly characterized CPE and 53 non-CPE controls. Isolates were grown on Mueller-Hinton agar (MHA); in the case of a false-negative result, isolates were additionally inoculated on Columbia blood agar (CBA) and CARBA PAcE was repeated. The test was performed according to the manufacturer's protocol.Results. CARBA PAcE showed an overall sensitivity and specificity of 72 % [confidence interval (CI) 62-80 %] and 91 % (CI 79-97 %), respectively, when isolates were grown on MHA. With growth on CBA, detection improved (especially of metallo-β-lactamases), resulting in an extrapolated sensitivity of 89 % (CI 81-94 %) for all carbapenemases and 96 % (CI 89-99 %) for the four major carbapenemases (NDM, OXA-48-like, KPC, VIM).Conclusion. CARBA PAcE is a simple and very rapid test for the detection of CPE which performs well for the major carbapenemases when isolates are grown on CBA. Laboratories should be aware of the limitations of this assay, such as moderate sensitivity when isolates are grown on more challenging agars such as MHA and the poor detection of some rare carbapenemases (e.g. IMI, OXA-58).
| S-EPMC8131015 | biostudies-literature
Project description:The immunochromatographic assay, NG-test Carba 5 (NG Biotech), has been evaluated for detection of carbapenemase-producing Enterobacterales (CPE) from spiked blood cultures (n = 205). It detected and discriminated in less than 30 minutes KPC, IMP, VIM, NDM, and OXA-48-like producers with a sensitivity and specificity of 97.7% and 96.1%, respectively. Thus, it might help the rapid optimization of treatment of bloodstream infections due to CPE.
| S-EPMC6496082 | biostudies-literature
Project description:For identification of polymyxin resistance in Enterobacteriaceae, we developed a rapid test that detects glucose metabolization associated with bacterial growth in the presence of a defined concentration of colistin or polymyxin B. Formation of acid metabolites is evidenced by a color change (orange to yellow) of a pH indicator (red phenol). To evaluate the test, we used bacterial colonies of 135 isolates expressing various mechanisms of colistin resistance (intrinsic, chromosomally encoded, and plasmid-mediated MCR-1) and 65 colistin-susceptible isolates. Sensitivity and specificity were 99.3% and 95.4%, respectively, compared with the standard broth microdilution method. This new test is inexpensive, easy to perform, sensitive, specific, and can be completed in <2 hours. It could be useful in countries facing endemic spread of carbapenemase producers and for which polymyxins are last-resort drugs.
| S-EPMC4880072 | biostudies-literature
Project description:This study was conducted to develop a cheap, rapid, and accurate modified combined-disk test (mCDT) approach to detect and differentiate KPC and MBL carbapenemases among clinical carbapenem-resistant Enterobacterales (CRE) isolates and simultaneously distinguish them from carbapenem-susceptible Enterobacterales (CSE) isolates. A total of 163 CRE and 90 third-generation cephalosporin-resistant Enterobacterales isolates were tested using imipenem and meropenem disks and different concentrations of carbapenemase inhibitors. The optimal sensitivity and specificity for detecting KPC carbapenemase were 97.2% and 100%, respectively. The sensitivity and specificity for detecting MBL carbapenemase were 100% and 100% with imipenem or meropenem and carbapenemase inhibitors within six hours. The inhibitory zone diameter of 18 mm for imipenem or meropenem disks without inhibitor could distinguish CRE from CSE isolates. Therefore, this mCDT approach may be a useful tool in clinical laboratories to detect CRE isolates and differentiate KPC and MBL producers, which is beneficial for patient management and hospital infection prevention and control.
| S-EPMC8458999 | biostudies-literature
Project description:BackgroundThe use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry is gradually spreading among large-scale laboratories; however, this method is impractical for small-scale laboratories. In laboratories without access to these rapid identification methods, problems related to them remain unsolved. In this study, we aimed to develop a rapid and inexpensive method to presumptively identify Enterobacterales using CHROMagar Orientation medium.MethodsThe algorithm for presumptive identification of Enterobacteriaceae using CHROMagar Orientation medium was based on our previous studies. Modified property tests for indole, lysine decarboxylase, ornithine decarboxylase, and hydrogen sulfide were performed to evaluate the differentiation of the bacterial species.ResultsUsing the type strains and clinical isolates, it was possible to conduct the property tests at a low cost, within 4 hours. The spot indole test was performed without any nonspecific reactions for the bacteria forming colored colonies. The presumptive identification of bacteria was thereby possible within 24 hours after specimen submission.ConclusionAll these results suggest that the rapid presumptive identification of Enterobacterales is possible with this new identification method using CHROMagar Orientation medium. This is therefore a prompt and economical method that can be used in routine laboratory work.
| S-EPMC7595914 | biostudies-literature
Project description:Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 - mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 – mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.
| S-EPMC7260631 | biostudies-literature
Project description:NG-Test CTX-M MULTI and NG-Test Carba 5 (NG Biotech) are two rapid in vitro immunochromatographic assays that are widely used for the detection of the most common extended spectrum beta-lactamases (ESBL) and carbapenemases in Enterobacterales. ESBL and carbapenemases are leading causes of morbidity and mortality worldwide and their rapid detection from positive blood cultures is crucial for early initiation of effective antimicrobial therapy in bloodstream infections (BSI) involving antibiotic-resistant organisms. In this study, we developed a rapid workflow for positive blood cultures for direct identification of Enterobacterales by MALDI-TOF mass-spectrometry, followed by detection of ESBL and carbapenemases using NG-Test CTX-M MULTI and NG-Test Carba 5 (NG Biotech). The workflow was evaluated using Enterobacterales isolates (n = 114), primarily Klebsiella species (n = 50) and Escherichia coli (n = 40). Compared to the standard testing approach in our institution using BD Phoenix, our new testing approach demonstrates 100% sensitivity and specificity for organism identification and detection of ESBL and carbapenemases. Implementation of a rapid workflow in diagnostic microbiology laboratories will enable more effective antimicrobial management of patients with BSI due to ESBL- and carbapenemase-producing Enterobacterales. IMPORTANCE The incidence of bloodstream infections (BSI) with extended spectrum beta-lactamase (ESBL) producing and carbapenemase producing Enterobacterales (CPE) is increasing at an alarming rate, for which only limited therapeutic options remain available. Rapid identification of these bacteria along with their antibiotic resistance mechanisms in positive blood cultures with Gram-negative bacteria will allow for early initiation of effective therapy and limit the overuse of broad-spectrum antibiotics in BSI (1). In this study we evaluated a combined approach of testing positive blood cultures directly, using MALDI-TOF MS followed by rapid immunochromatographic tests, for the detection of ESBLs and CPEs. Our approach demonstrates 100% sensitivity and specificity for the identification of Enterobacterales and detection of ESBLs and CPEs in positive blood culture with a turnaround time (TAT) of ≤60 min compared to a TAT of 48 h required by conventional culture and susceptibility testing methods.
| S-EPMC8653814 | biostudies-literature
Project description:Colistin resistance in Enterobacterales
| PRJEB47075 | ENA