2019 Volume 68 Issue 4 Pages 707-711
We evaluated the performance of Xpert C. difficile “Cepheid” (Beckman Coulter, Inc.) for Clostridioides difficile toxin detection. Fecal samples were obtained from 46 patients suspected of having C. difficile-associated diarrhea (CDAD) in our hospital and were analyzed from April to August 2018. The C. difficile immunochromatography (IC) test results showed that these samples were positive for glutamate dehydrogenase (GDH). As a control, the GE immunochromato-CD GDH/TOX test [Nissui] and toxigenic culture (TC) were carried out. Toxin A/B was detected in 19 TC samples and nine IC samples, whereas 19 samples were found positive for toxin B by GeneXpert. Two of them showed a negative result obtained by the Xpert method and a positive result obtained by the IC method only, and TC showed growth of Clostridium clostridioforme and negative results for toxin A/B of C. difficile. The rate of agreement between results obtained by the TC method and those obtained by the IC method was 69.6%, and that between results obtained by the TC method and those obtained using GeneXpert was 100%. Samples found positive for toxin A/B by the IC method, negative for toxin B by the Xpert method, and negative for toxin A/B by the TC method showed a different bacterial growth compared with samples found positive for toxin A/B of C. difficile by the TC method. The IC method showed a false positive result. The results of C. difficile toxin detection using the GeneXpert method were consistent with those obtained by the TC method. Therefore, the use of GeneXpert suggests the possibility of rapid diagnosis and eliminates the need for unnecessary infection prevention measures and treatment.
