[Evaluation of Quick Chaser CD GDH/TOX, a Rapid Diagnostic Kit for Simultaneous Detection of Clostridioides difficile Antigen and Toxin A/B, in Fecal Specimens]

Abstract

For Clostridioides difficile infections, highly sensitive rapid diagnostic test kits are necessary for prompt diagnose and infection control. In this study, we evaluated "Quick Chaser CD GDH/TOX" (evaluation kit), a rapid diagnostic kit for C. difficile, using 65 clinical stool specimens, comparing with GE test immunochromato-CD GDH/TOX "Nissui" (GE test) and TECHLAB C. DIFF QUIK CHEK COMPLETE (QUIK CHEK). The results of the evaluation kit showed a high concordance rate; 100% the positive concordance rate (31/31) and 97.1% the negative concordance rate (33/34) of GDH, 94.1% the positive concordance rate (16/17) and 97.9% the negative concordance rate (47/48) of toxin against GE test, respectively. Also 96.9% the positive concordance rate (31/32) and 97.0% the negative concordance rate (32/33) of GDH, 100% the positive concordance rate (12/12) and 90.6% the negative concordance rate (48/53) of toxin against QUIK CHEK, respectively. Additionally, comparison of discrepancy cases between kits based on Nucleic Acid Amplification test, one false negative each for GDH and toxin in the evaluation kit, two false negatives for GDH and one false negative for toxin in the GE test, one false negative for GDH and six false negatives for toxin in QUIK CHEK, and no false positive cases were observed. Therefore, the detection sensitivity of GDH and toxin of the evaluation kit was equivalent to that of two types of comparative kits.