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J Antimicrob Chemother. 2016 May;71(5):1213-6. doi: 10.1093/jac/dkv468. Epub 2016 Jan 13.

A two-centre evaluation of RAPIDEC® CARBA NP for carbapenemase detection in Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter spp.

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Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.
Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI) Reference Unit, Public Health England, 61 Colindale Avenue, London NW9 5EQ, UK.
Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden



We evaluated the RAPIDEC(®) CARBA NP assay (bioMérieux SA, Marcy-l'Étoile, France), a colorimetric test for rapid detection of carbapenemases, at two sites: Karolinska University Laboratory and PHE's national reference laboratory.


A total of 138 bacterial isolates previously characterized as positive for class A, B and/or D carbapenemase genes and 138 supposed non-carbapenemase producers were tested with RAPIDEC(®) CARBA NP according to the manufacturer's protocol. Two carbapenemase-producing isolates carried both NDM and OXA-48-like genes. Molecular detection of the expected carbapenemase gene(s) was used as the gold standard, and was performed by conventional and real-time PCR in-house assays.


The RAPIDEC(®) CARBA NP assay detected 135 of 138 carbapenemase producers; one OXA-48-producing Klebsiella pneumoniae and two Acinetobacter baumannii producing OXA-23 or OXA-24 were not detected. Among 'negative' controls, 135 of 138 isolates were negative by RAPIDEC(®) CARBA NP. The exceptions were one Klebsiella oxytoca, which was later found to produce GES-5 carbapenemase, one Pseudomonas aeruginosa with OprD loss and increased efflux, and one Enterobacter cloacae with impermeability. When numbers were adjusted for the GES-5 producer, the overall sensitivity of the RAPIDEC(®) CARBA NP test was 97.8% and its specificity was 98.5%.


The assay took less than 2.5 h to carry out, was user-friendly and had a high overall performance, making it an attractive option for clinical laboratories.

[Indexed for MEDLINE]

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