Evaluation of the Check-Points Check MDR CT103 and CT103 XL Microarray Kits by Use of Preparatory Rapid Cell Lysis

Abstract

Using a rapid bacterial lysis method, the Check MDR CT103 and CT103 XL microarrays demonstrated accuracies of 98.1% and 94.2%, respectively, for detection of known resistance genes in 108 multidrug-resistant Gram-negative bacilli. In 45 isolates, 49 previously unrecognized extended-spectrum ␤-lactamase or plasmid AmpC targets were detected and confirmed by conventional PCR. Multidrug-resistant Enterobacteriaceae (MDRE), especially those producing carbapenemases, are of concern to physicians and laboratorians worldwide. MDRE have acquired resistance through plasmid transfer, with or without chromosomal mutation (1). The ability of clinical laboratories to rapidly detect and characterize MDRE is a sentinel defense against these threatening pathogens. Current laboratory tools directed at MDRE and their associated resistances are largely focused on phenotypic methods, such as selective indicator media (e.g., commercial chromogenic media), antimicrobial susceptibility testing (AST) systems to assess MICs, and confirmatory tests for enzyme expression (e.g., modified Hodge test, Carba NP test) (2-5).A multitude of PCR assays have been described for detecting resistance genes in isolated bacteria (6-10). Sensitivity and specificity are generally excellent; however, such assays typically target a relatively small number of ␤-lactamase genes based largely on prevalence. MDRE may carry one or more plasmids and may simultaneously harbor multiple antimicrobial resistance genes and resistance mechanisms that affect the same antimicrobial agents (11). Given this, a comprehensive approach to detect resistance genes may be appropriate for MDRE. Studies employing microarray-based molecular tests that target a large number of resistance genes suggest that such platforms may serve this role (5, 12-15). Cuzon et al. evaluated the Check-Points Check MDR CT103 (Check-Points Health B.V., Wageningen, The Netherlands) microarray kit by using 187 clinical isolates and reported excellent specificity (16). This kit can detect 6 AmpC genes/gene groups (CMY-I/MOX, ACC, DHA, ACT/MIR, CMY-II, FOX), 5 carbapenemase genes/gene groups (KPC, NDM, VIM, IMP, OXA-48-like), and genes encoding CTX-M-1, -2, -8, -9, and -25 groups and can detect and distinguish wild-type bla SHV and bla TEM alleles from those with point mutations conferring extended-spectrum ␤-lactamase (ESBL) production (16).(This study was presented in part at the 54th Interscience Conference on Antimicrobial Agents and Chemotherapy, Washington, DC, 5 to 9 September 2014.)We evaluated the Check MDR CT103 kit and the expanded CT103 XL kit (Check-Points Health B.V.) following the manufacturer's suggested protocol but substituting a previously described time-and reagent-saving rapid bacterial lysis step (6) for DNA preparation. The CT103 XL kit contains additional targets beyond those included in the CT103 kit, including carbapenemases most commonly found in nonfermenting Gram-negative bacilli rather than Enterobacteriaceae, specifically GES, GIM, SPM, OXA-23-like, OXA-24/40-like, and OXA-...

Detection of carbapenemases, AmpC and ESBL genes in Acinetobacter isolates from ICUs by DNA microarray

“…The results of CT 103 XL microarray showed the high accuracy for the detection of β-lactamases in A. baumannii. The similar findings have been reported by Cunningham et al (2016) and Juiz et al (2014) from microarray technique for characterization of resistance mechanism in MDR Enterobacteriaceae (MDRE) and Pseudomonas aeruginosa.…”

“…baumannii, as well (Cunningham et al, 2016;Bogaerts et al, 2012). In this study, a novel array Check-Points carbapenemases, ESBLs and AmpCs Microarray (Check-MDR CT103XL; Check-Points B.V., Wageningen, the Netherlands) was used to detect all the previously targeted genes,…”

Evaluation of a New Commercial Microarray Platform for the Simultaneous Detection of β-Lactamase and mcr-1 and mcr-2 Genes in Enterobacteriaceae

“…Therefore, the new CT103XL platform showed 100% accuracy in identifying mcr-1 and mcr-2. We also noted that all bla genes were correctly identified (Table S1), thereby confirming previous validations (7,14,15).…”

Detection and Characterization of <i>β</i>-Lactamase Encoding Genes in Carbapenem Non-Susceptible Gram-Negative Bacteria and Susceptibility of Isolates to Ceftazidime-Avibactam at a New York City Community Hospital

“…However, recent studies have demonstrated sensitivities and specificities of 100% and accuracies of 94% for the detection of known resistance genes using the Check-Points MDR CT103 XL microarray kit (4,5).…”