Effective detection of toxigenic Clostridium difficile by a two-step algorithm including tests for antigen and cytotoxin.
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.
Ticehurst
John R
JR
Division of Medical Microbiology, The Johns Hopkins Hospital/Meyer B1-193, 600 North Wolfe St., Baltimore, Maryland 21287-7093, USA. jticehur@jhmi.edu
Aird
Deborah Z
DZ
Dam
Lisa M
LM
Borek
Anita P
AP
Hargrove
John T
JT
Carroll
Karen C
KC
D000465:Algorithms; D000942:Antigens, Bacterial / Q000032:analysis; D001431:Bacteriological Techniques / Q000191:economics / Q000379:methods* / Q000706:statistics & numerical data; D016360:Clostridioides difficile / Q000201:enzymology / Q000276:immunology / Q000302:isolation & purification* / Q000472:pathogenicity; D003365:Costs and Cost Analysis; D003603:Cytotoxins / Q000032:analysis; D004761:Enterocolitis, Pseudomembranous / Q000175:diagnosis; D005969:Glutamate Dehydrogenase / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques / Q000191:economics / Q000379:methods / Q000706:statistics & numerical data; D009500:Neutralization Tests; D012680:Sensitivity and Specificity; D012985:Software Design
D000942:Antigens, Bacterial; D003603:Cytotoxins; D005969:Glutamate Dehydrogenase