Evaluation of methods for detection of toxins in specimens of feces submitted for diagnosis of Clostridium difficile-associated diarrhea.
Clostridium difficile is the principal pathogen associated with hospital-acquired acute diarrheal disease. We have evaluated the performances of six approaches for diagnosis of C. difficile-associated diarrhea (CDAD). Consecutive stool specimens (n = 200) from 133 patients were examined by cytotoxin assay, by culture of C. difficile on cycloserine-cefoxitin-fructose agar, and by toxin detection using four rapid immunoassay systems (Oxoid Toxin A test, ImmunoCard Toxin A test, TechLab Tox A/B II test, and Premier Toxins A&B test). A diagnosis of CDAD was established for 35 (27%) patients (representing 29% of specimens). The adjusted sensitivity and specificity of the methods were, respectively, 98 and 99% for the cytotoxin assay, 54 and 99% for ImmunoCard, 50 and 98% for Oxoid, 79 and 98% for TechLab, 80 and 98% for Premier, and 57 and 100% for culture. The TechLab and Premier assays are acceptable tests for diagnosis of CDAD but are not equivalent to the cytotoxin assay.
O'Connor
D
D
Microbiology Laboratory, Portiuncula Hospital, Ballinasloe, County Galway, Galway, Ireland. labmanager@portiuncula.com
Hynes
P
P
Cormican
M
M
Collins
E
E
Corbett-Feeney
G
G
Cassidy
M
M
D000328:Adult; D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000032:analysis*; D001431:Bacteriological Techniques; D016360:Clostridioides difficile / Q000302:isolation & purification* / Q000378:metabolism; D003015:Clostridium Infections / Q000175:diagnosis* / Q000382:microbiology; D003470:Culture Media; D003967:Diarrhea / Q000175:diagnosis* / Q000382:microbiology; D004768:Enterotoxins / Q000032:analysis*; D005243:Feces / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003470:Culture Media; D004768:Enterotoxins; C041348:tcdA protein, Clostridium difficile; C031815:toxB protein, Clostridium difficile