Evaluation of Xpert C. difficile, BD MAX Cdiff, IMDx C. difficile for Abbott m2000, and Illumigene C. difficile Assays for Direct Detection of Toxigenic Clostridium difficile in Stool Specimens.
10.3343/alm.2016.36.2.131
- Author:
Bo Moon SHIN
1
;
Sun Mee YOO
;
Won Chang SHIN
Author Information
1. Department of Laboratory Medicine, Sanggye Paik Hospital, School of Medicine, Inje University, Seoul, Korea. bmshin@unitel.co.kr
- Publication Type:Evaluation Studies ; Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
Clostridium difficile;
NAAT;
Culture;
Evaluation;
Performance
- MeSH:
Bacterial Proteins/genetics;
Bacterial Toxins/genetics;
Clostridium Infections/*diagnosis/microbiology;
Clostridium difficile/*genetics/isolation & purification;
DNA, Bacterial/*analysis/metabolism;
Enterotoxins/genetics;
Feces/*microbiology;
Humans;
*Multiplex Polymerase Chain Reaction;
Reagent Kits, Diagnostic;
Sensitivity and Specificity
- From:Annals of Laboratory Medicine
2016;36(2):131-137
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: We evaluated the performance of four commercial nucleic acid amplification tests (NAATs: Xpert C. difficile, BD MAX Cdiff, IMDx C. difficile for Abbott m2000, and Illumigene C. difficile) for direct and rapid detection of Clostridium difficile toxin genes. METHODS: We compared four NAATs on the same set of 339 stool specimens (303 prospective and 36 retrospective specimens) with toxigenic culture (TC). RESULTS: Concordance rate among four NAATs was 90.3% (306/339). Based on TC results, the sensitivity and specificity were 90.0% and 92.9% for Xpert; 86.3% and 89.3% for Max; 84.3% and 94.4% for IMDx; and 82.4% and 93.7% for Illumigene, respectively. For 306 concordant cases, there were 11 TC-negative/NAATs co-positive cases and 6 TC-positive/NAATs co-negative cases. Among 33 discordant cases, 18 were only single positive in each NAAT (Xpert, 1; Max, 12; IMDx, 1; Illumigene, 4). Positivity rates of the four NAATs were associated with those of semi-quantitative cultures, which were maximized in grade 3 (>100 colony-forming unit [CFU]) compared with grade 1 (<10 CFU). CONCLUSIONS: Commercial NAATs may be rapid and reliable methods for direct detection of tcdA and/or tcdB in stool specimens compared with TC. Some differences in the sensitivity of the NAATs may partly depend on the number of toxigenic C. difficile in stool specimens.