Multiplex Immunochromatographic Detection of OXA-48, KPC, and NDM Carbapenemases: Impact of Inoculum, Antibiotics, and Agar

Abstract

For the rapid detection of carbapenemase-producing (CPE), immunochromatographic lateral flow tests (ICT) have recently been developed. The aim of this study was to assess the new multiplex ICT Resist-3 O.K.N. and to investigate if it can be performed directly from susceptibility testing plates. Additionally, the impact of the inoculum and carbapenem disks on sensitivity and specificity was evaluated. The new ICT was challenged using 63 carbapenem-resistant (CRE) isolates, including 51 carbapenemase producers. It was assessed under five different conditions directly from Mueller-Hinton agar (MHA): 1 μl or 10 μl of inoculum harvested in the absence of antibiotic pressure or 1 μl taken from the inhibition zone of either an ertapenem, imipenem, or meropenem disk. The sensitivity of the ICT was 100% for OXA-48-like and KPC carbapenemases and 94.4% for the NDM carbapenemase with the 1-μl inoculum. When harvested adjacent to a carbapenem disk, the sensitivity increased to 100%. Additionally, with zinc-supplemented MHA, both the sensitivity increased and the NDM band became visible faster (mean time, 8 ± 3.9 min for MHA compared to 1.9 ± 1.5 min for MHA plus zinc; = 0.0016). The specificity of the ICT was 100%. The Resist-3 O.K.N. ICT is a sensitive and rapid test for the detection of three highly prevalent carbapenemases. However, false-negative results for NDM can occur. We recommend an inoculum of 1 μl that is harvested adjacent to an ertapenem or meropenem disk and the use of agars with sufficient zinc content to achieve the best performance.

NDM Metallo-β-Lactamases and Their Bacterial Producers in Health Care Settings

“…The lateral flow immunoassay (LFIA) is an antibodybased method developed to detect different types of carbapenemases, which has been validated. It allows the specific detection of NDM enzymes in singleplex (for NDM only) (197) or multiplex (for NDM and other major types of carbapenemases) (198,199) assays by using specific antibodies. These assays are easy to perform and have a short turnaround time, as they yield results from cultured colonies within 15 min.…”

Phenotypic Detection of Carbapenemase-Producing Organisms from Clinical Isolates

“…Multiplex lateral flow immunoassays (LFIAs) are actively being investigated as an approach to identify the specific carbapenemase group being produced, even when multiple carbapenemases are present simultaneously (11)(12)(13)(14)(15)(16)(17). Inhibitor-based methods are alternative phenotypic approaches that can be used to differentiate between carbapenemases by applying class-specific inhibitors.…”

“…A number of LFIAs have been recently developed but generally enable the detection of one or a few of the most epidemiologically important carbapenemases. LFIAs have been developed for NDM production (14), IMP-production (15), OXA-48-like production (14), KPC and OXA-48-like production (16), and KPC, NDM, and OXA-48-like production (12). Available data suggest that LFIAs produce accurate results from cultured isolates within 15 min.…”

Development of an immunochromatographic lateral flow strip test for the rapid detection of diclofenac in medicinal wine

“…ELISAs eliminate sophisticated sample pretreatment and can tolerate certain matrix interferences because of washes between steps. Compared with ELISAs, immunochromatographic lateral flow strip test (ILFST) is simpler and rapid immunoassay that has been used in detecting pesticides (Byzova, Urusov, Zherdev, & Dzantiev, 2018;Ismail et al, 2016), veterinary drugs (Chen et al, 2017;Shelver & Smith, 2018), mycotoxins (Di Nardo et al, 2019;Majdinasab, Zareian, Zhang, & Li, 2019), bacteria (Canver et al, 2019;Saleh, Göttig, & Hamprecht, 2018), and viruses (Lyoo et al, 2017;Senthilkumaran et al, 2017). ILFST integrates all the required reagents into itself and can provide the results within 10 min that can be determined both qualitatively and quantitatively with unaided eyes and a strip reader, respectively.…”