Banz, A, Lantz, A, Riou, B et al. (4 more authors) (2018) Sensitivity of single-molecule array assays to detect Clostridium difficile toxins in comparison to conventional laboratory testing algorithms. Journal of Clinical Microbiology, 56 (8). e00452-18. ISSN 0095-1137
Abstract
Guidelines recommend the use of an algorithm for the laboratory diagnosis of Clostridium difficile infection (CDI). Enzyme immunoassays (EIAs) detecting C. difficile toxins cannot be used as standalone tests due to suboptimal sensitivity, and molecular tests suffer from nonspecificity by detecting colonization. Sensitive immunoassays have recently been developed to improve and simplify CDI diagnosis. Assays detecting CD toxins have been developed using single-molecule array (SIMOA) technology. SIMOA performance was assessed relative to a laboratory case definition of CDI defined by positive glutamate dehydrogenase (GDH) screen and cell cytotoxicity neutralizing assay (CCNA). Samples were tested with SIMOA assays and a commercial toxin EIA to compare performance, with discrepancy resolution using a commercial nucleic acid-based test and a second cell cytotoxicity assay. The SIMOA toxin A and toxin B assays showed limits of detection of 0.6 and 2.9 pg/ml, respectively, and intra-assay coefficients of variation of less than 10%. The optimal clinical thresholds for the toxin A and toxin B assays were determined to be 22.1 and 18.8 pg/ml, respectively, with resultant sensitivities of 84.8 and 95.5%. In contrast, a high-performing EIA toxin test had a sensitivity of 71.2%. Thus, the SIMOA assays detected toxins in 24% more samples with laboratory-defined CDI than the high performing toxin EIA (95% [63/66] versus 71% [47/66]). This study shows that SIMOA C. difficile toxin assays have a higher sensitivity than currently available toxin EIA and have the potential to improve CDI diagnosis.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | Copyright © 2018 Banz et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Medicine and Health (Leeds) > Institute of Molecular Medicine (LIMM) (Leeds) > Section of Molecular Gastroenterology (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 08 Jan 2019 15:39 |
Last Modified: | 25 Jun 2023 21:39 |
Status: | Published |
Publisher: | American Society for Microbiology |
Identification Number: | 10.1128/JCM.00452-18 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:140635 |