Loop-Mediated Isothermal Amplification Compared to Real-Time PCR and Enzyme Immunoassay for Toxigenic Clostridium difficile Detection
- 1 March 2012
- journal article
- research article
- Published by American Society for Microbiology in Journal of Clinical Microbiology
- Vol. 50 (3), 640-645
- https://doi.org/10.1128/jcm.01014-11
Abstract
Clostridium difficile infection is the primary cause of health care-associated diarrhea. While most laboratories have been using rapid antigen tests for detecting C. difficile toxins, they have poor sensitivity; newer molecular methods offer rapid results with high test sensitivity and specificity. This study was designed to compare the performances of two molecular assays (Meridian illumigene and BD GeneOhm) and two antigen assays (Wampole Quik Chek Complete and TechLab Tox A/B II) to detect toxigenic C. difficile . Fecal specimens from hospitalized patients ( n = 139) suspected of having C. difficile infection were tested by the four assays. Nine specimens were positive and 109 were negative by all four methods. After discrepant analysis by toxigenic culture ( n = 21), the total numbers of stool specimens classified as positive and negative for toxigenic C. difficile were 21 (15%) and 118 (85%), respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were as follows: GeneOhm (95.2%, 100%, 100%, and 99.2%), illumigene (95.2%, 96.6%, 83.3%, and 99.2%), Tox A/B II (52.4%, 97.5%, 78.6%, and 92.4%), and Quik Chek Complete (47.6%, 100%, 100%, and 91.9%). The illumigene assay performed comparably to the GeneOhm assay with a slight decrease in test specificity; the sensitivities of both far exceeded those of the antigen assays. The clinical characteristics of the concordant and discrepant study patients were similar, including stool consistency and frequency. In the era of rapid molecular-based tests for toxigenic C. difficile , toxin enzyme immunoassays (EIAs) should no longer be considered the standard of care.Keywords
This publication has 31 references indexed in Scilit:
- Impact of Clinical Symptoms on Interpretation of Diagnostic Assays for Clostridium difficile InfectionsJournal of Clinical Microbiology, 2011
- Evaluation of a Loop-Mediated Isothermal Amplification Assay for Diagnosis of Clostridium difficile InfectionsJournal of Clinical Microbiology, 2011
- Rapid and Sensitive Loop-Mediated Isothermal Amplification Test for Clostridium difficile Detection Challenges Cytotoxin B Cell Test and Culture as Gold StandardJournal of Clinical Microbiology, 2011
- C. Diff Quik Chek Complete Enzyme Immunoassay Provides a Reliable First-Line Method for Detection of Clostridium difficile in Stool SpecimensJournal of Clinical Microbiology, 2010
- Evaluation of Diagnostic Tests for Clostridium difficile InfectionJournal of Clinical Microbiology, 2010
- Evaluation of a New Commercial TaqMan PCR Assay for Direct Detection of the Clostridium difficile Toxin B Gene in Clinical Stool SpecimensJournal of Clinical Microbiology, 2009
- Comparison of a Rapid Molecular Method, the BD GeneOhm Cdiff Assay, to the Most Frequently Used Laboratory Tests for Detection of Toxin-Producing Clostridium difficile in Diarrheal FecesJournal of Clinical Microbiology, 2009
- Comparison of Nine Commercially Available Clostridium difficile Toxin Detection Assays, a Real-Time PCR Assay for C . difficile tcdB , and a Glutamate Dehydrogenase Detection Assay to Cytotoxin Testing and Cytotoxigenic Culture MethodsJournal of Clinical Microbiology, 2009
- Algorithm Combining Toxin Immunoassay and Stool Culture for Diagnosis of Clostridium difficile InfectionJournal of Clinical Microbiology, 2009
- Comparison of a Commercial Real-Time PCR Assay for tcdB Detection to a Cell Culture Cytotoxicity Assay and Toxigenic Culture for Direct Detection of Toxin-Producing Clostridium difficile in Clinical SamplesJournal of Clinical Microbiology, 2009