The University of Melbourne
Evaluation of Xpert Carba-R and NG-Test CARBA-5 for detection of carbapenemases from clinical isolates - Phoebe Webster (MDU PHL).pdf (574.52 kB)

Evaluation of Xpert Carba-R and NG-Test CARBA-5 for detection of carbapenemases from clinical isolates

This item contains files with download restrictions

The global spread of carbapenemase-producing organisms (CPOs) is a critical medical and public health issue. Rapid detection of carbapenem-non-susceptibility within bacterial isolates is crucial to assist in the delivery of effective antimicrobial therapy. Additionally, detection of carbapenemase genes is necessary to control the spread of these organisms, particularly in hospital settings. This evaluation was designed to assess the performance of the q-PCR based Xpert® Carba-R assay (Cepheid) and the NG-test® CARBA-5 immunoassay (NG Biotech) in detecting blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP carbapenemase genes in a panel of bacterial species received at the Microbiological Diagnostic Unit Public Health Laboratory (MDU PHL) under the Victorian guideline on carbapenemase producing organisms.

A total of 67 carbapenemase-producing bacterial isolates representative of those seen in Victoria over the last 10 years containing one or more carbapenemase genes were tested in parallel on the Xpert Carba-R and the NG-test CARBA-5. Additional bacterial species and genotypes to those validated by the commercial assays were selected for this study, to encompass a broader range of CPOs reported in Victoria. These included Enterobacteriaceae (n=48), Serratia spp. (n=5), Pseudomonas spp. (n=13), and Providencia spp. (n=1), and gene variants either not tested or predicted to be detected by in silico analysis such as OXA-94, OXA-484; IMP-26, IMP-34, IMP-62; NDM-19; and KPC-23, KPC-33.

Of the 67 isolates, consistent results were obtained for 65 isolates on the Xpert Carba-R (97.01% accuracy) and 67 isolates on the NG-test CARBA-5 (100% accuracy).

Xpert Carba-R and NG-test CARBA-5 are rapid and cost-efficient tests to detect carbapenemases across numerous bacterial species, and provide a useful resource in the identification/confirmation of CPOs.


Usage metrics

    University of Melbourne



    Ref. manager