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Effective detection of toxigenic Clostridium difficile by a two-step algorithm including tests for antigen and cytotoxin.

John R Ticehurst·Deborah Z Aird·Lisa M Dam·Anita P Borek·John T Hargrove·Karen C Carroll
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Abstract

We evaluated a two-step algorithm for detecting toxigenic Clostridium difficile: an enzyme immunoassay for glutamate dehydrogenase antigen (Ag-EIA) and then, for antigen-positive specimens, a concurrent cell culture cytotoxicity neutralization assay (CCNA). Antigen-negative results were > or = 99% predictive of CCNA negativity. Because the Ag-EIA reduced cell culture workload by approximately 75 to 80% and two-step testing was complete in < or = 3 days, we decided that this algorithm would be effective. Over 6 months, our laboratories' expenses were US dollar 143,000 less than if CCNA alone had been performed on all 5,887 specimens.

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AlgorithmsAntigens, BacterialBacteriological TechniquesClostridioides difficileCosts and Cost AnalysisCytotoxinsEnterocolitis, PseudomembranousGlutamate DehydrogenaseHumansImmunoenzyme TechniquesNeutralization TestsSensitivity and SpecificitySoftware DesignComparative StudyEvaluation StudyJournal Article

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John R Ticehurst, Deborah Z Aird, Lisa M Dam, Anita P Borek, John T Hargrove, Karen C Carroll. 2006. Effective detection of toxigenic Clostridium difficile by a two-step algorithm including tests for antigen and cytotoxin.. https://doi.org/10.1128/jcm.44.3.1145-1149.2006

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