ABSTRACT
The objective of this study was to evaluate the accuracy of the MDR Direct Flow Chip Kit for the detection of antimicrobial resistance (AMR) determinants from bacterial colonies. Ninety-two clinical isolates with known AMR determinants genotypically characterized were used. The MDR Direct Flow Chip Kit is a microarray-based assay that included 55 AMR determinants for beta-lactams (23), quinolones (13), aminoglycosides (5), macrolides (5), sulfonamides (3), colistin (2), vancomycin (2), chloramphenicol (1), and linezolid (1). The MDR Direct Flow Chip Kit correctly detects 52 of 53 AMR determinants tested. The cfr gene (linezolid resistance) was not detected. The global sensibility, specificity, positive predictive value, and the negative predictive value calculated were 98%, 100%, 100%, and 97%. The Cohen's Kappa coefficient calculated was 0.97 [95% Confidence Interval (0.90-1.03)]. In conclusion, the MDR Direct Flow Chip is an accurate assay for the detection of multiple AMR determinants in one simple reaction.
Subject(s)
Anti-Bacterial Agents , Anti-Infective Agents , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Linezolid , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial/geneticsABSTRACT
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
INTRODUCCIÓN: El ensayo "AMR Direct Flow Chip Kit" permite detectar simultáneamente la presencia de una gran variedad de marcadores genotípicos de resistencia bacteriana. Evaluamos su rendimiento utilizando colonias aisladas como material de partida. El ensayo aludido ha sido aprobado por el Área Económica Europea como un dispositivo adecuado para el diagnóstico in vitro (CE IVD) utilizando muestras clínicas. MÉTODOS: El estudio ha incluido 210 aislados bacterianos con uno o más genes de resistencia a los antimicrobianos, incluidos genes plasmídicos que codifican β-lactamasas de espectro extendido (SHV y CTX-M) y carbapenemasas (GES, SME, KPC, NMC/IMI, SIM, GIM, SPM, NDM, VIM, IMP y OXA), mecA, vanA y vanB, y 30 controles. RESULTADOS: El ensayo mostró una sensibilidad y especificidad del 100% para todos los genes diana incluidos en la matriz. CONCLUSIÓN: El «AMR Direct Flow Chip Kit» es un ensayo fiable para la detección de genes que comúnmente confieren resistencia a β-lactámicos y vancomicina en bacterias grampositivas y gramnegativas a partir de colonias aisladas en cultivo
Subject(s)
DNA, Bacterial/isolation & purification , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria/genetics , beta-Lactamases/genetics , Drug Resistance, Microbial , DNA, Bacterial/genetics , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Microbial Sensitivity Tests , In Vitro TechniquesABSTRACT
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 ß-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 ß-lactams and vancomycin from isolated colonies in culture of Gram-positive and Gram-negative bacteria.
