Evaluation of the "AMR Direct Flow Chip Kit" DNA microarray for detecting antimicrobial resistance genes directly from rectal and nasopharyngeal clinical samples upon ICU admission

Introduction: Prompt detection of antibiotic resistance genes in healthcare institutions is of utmost importance in tackling the spread of multi-drug resistant micro-organisms. We evaluated the Antimicrobial Resistance (AMR) Direct Flow Chip Kit versus phenotypic screening assays for rectal and nasopharyngeal specimens upon ICU admission.

Methods: A total of 184 dual specimens (92 rectal and 92 nasopharyngeal swabs) from 92 patients were collected from 11/2017 to 8/2018. All swabs were subjected to both AMR and phenotypic tests according to their origin. The degree of agreement of the two methods was assessed by the kappa coefficient.

Results: The kappa coefficient showed perfect agreement for MRSA, ESBLs, oxacillinases and vancomycin resistance genes (1.000, p<0.01) and very good agreement for mecA-positive CoNS, KPC-carbapenemases and metallo-beta-lactamases (0.870, p<0.01; 0.864, p<0.01; and 0.912, p<0.01, respectively).

Conclusion: The AMR Direct Flow Chip Kit is a useful alternative to phenotypic testing for rapid detection of resistance markers.