Evaluation of the VIDAS CDAB Kits for the Detection of the Clostridium difficile Toxins A and B.
10.5145/KJCM.2008.11.2.107
- Author:
Jung Oak KANG
1
;
Bo Moon SHIN
;
Dongsoo HAN
;
Tae Yeal CHOI
Author Information
1. Department of Laboratory Medicine, Hanyang University College of Medicine, Seoul, Korea. jokang@hanyang.ac.kr
- Publication Type:Original Article
- Keywords:
Clostridium difficile;
Toxins;
Enzyme immunoassay;
PCR
- MeSH:
Clostridium;
Clostridium difficile;
Diagnostic Errors;
Humans;
Immunoassay;
Immunoenzyme Techniques;
Korea;
Polymerase Chain Reaction;
Sensitivity and Specificity
- From:Korean Journal of Clinical Microbiology
2008;11(2):107-111
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Since the emergence of variant Clostridium difficile strains that fail to produce detectable toxin A, diagnostic kits targeted to detect toxin A only showed a considerable rate of false negative results. The aim of this study was to evaluate a toxins A and B (toxins A/B) detection kit recently marketed in Korea, and to compare toxin positive rates before and after introduction of the new kit. METHODS: The results of 5,783 toxin A assays performed during the 7-year period from 2001 through 2007 were analyzed and compared them to the toxins A/B assay data of 519 samples obtained from January to June 2008 in a university hospital. An enzyme-linked fluorescent immunoassay for toxins A/B (VIDAS C. difficile Toxin A & B, bioMerieux SA, France: VIDAS CDAB) and PCR for toxin genes A/B were performed directly in 102 stool samples from hospitalized patients. RESULTS: The positive rates of toxin A assays tended downward annually from 2001 to 2007 (16.3%, 17.8%, 13.9%, 11.4%, 13.8%, 8.2%, and 5.8%, respectively), but increased to 12.1% in 2008 after changing to the toxin A/B detection kit. The concordant rate of the VIDAS CDAB kit with the PCR method was 82.4%. Compared to the PCR method, the sensitivity and specificity of the toxin A/B kit were 60.7% and 90.5% respectively. CONCLUSION: Testing kits for C. difficile toxin A only could result in a misdiagnosis more frequently than the testing kit for toxins A/B. The sensitivity of the newly launched toxin A/B detection kit from bioMerieux SA needs to be improved, but it showed a good specificity
