Abstract Objectives Carbapenemase-producing Gram-negative bacteria represent a major clinical challenge. Rapid detection and characterization of carbapenemase group is essential for guiding therapy and for infection control. We evaluated the performance of Certest ResisCheck® Carbapenemases, a novel lateral flow immunoassay (LFIA), for detecting the main carbapenemase groups from bacterial culture. Materials and methods A multicentre collection of 351 well-characterized clinical Gram-negative isolates, studied by whole-genome sequencing, was tested using this assay. 57 KPC, 53 NDM, 63 VIM, 68 OXA-48-like, 64 IMP and 100 carbapenem resistant non-carbapenemase producers were included. Results The LFIA showed an overall sensitivity of 96.4% and specificity of 100%. The positive predictive value (PPV) was 100%, and the negative predictive value (NPV) was 91.7%. No false-positives or cross-reactions with extended-spectrum β-lactamases (ESBLs) or cephalosporinases were observed either with isolates harbouring multiple carbapenemases. Detection rates for IMP and NDM variants reached 100%. Sensitivity for KPC, OXA-like and VIM was slightly lower (93.0%, 95.6% and 96.8%, respectively). Nine false-negative results were observed: KPC-31 (n = 4), VIM-63 (n = 2) and OXA-1054-producing (n = 3) isolates. Increasing the bacterial inoculum managed to obtain a positive result for KPC-31 and VIM-63, but OXA-1054 remained undetected. Conclusions Certest ResisCheck® Carbapenemases is a rapid, accurate, and reliable tool for detecting carbapenemases in clinical settings. While some rare variants may escape detection, its strong performance across diverse bacterial species supports its use as part of routine diagnostics to guide timely antimicrobial therapy and control the spread of resistance.
Monge-Olivares et al. (Tue,) studied this question.