Aldeen W E, Bingham M, Aiderzada A, Kucera J, Jense S, Carroll K C
Associated Regional and University Pathologists, Inc. Salt Lake City, UT 84108, USA.
Diagn Microbiol Infect Dis. 2000 Apr;36(4):211-3. doi: 10.1016/s0732-8893(00)00113-9.
The TOX A/B Test (Techlab, Blacksburg, VA, USA) was compared to cell culture cytotoxicity assay on 1109 consecutive diarrheal stool samples collected from patients with the presumptive diagnosis of Clostridium difficile disease. The TOX A/B Test is an enzyme immunoassay in a microtiter format that detects both toxins A and B. The procedure used for this study takes approximately 1.5 h to perform. Cell culture cytotoxicity was performed by using a fibroblast cell line in a microtiter format read at 4 h, 24 h, and 48 h. One hundred ninety-four of the 1109 samples were positive by the "gold standard" cytotoxicity assay, whereas 189 were positive by EIA. There was a 98.5% agreement between the two assays. When compared to the cytotoxicity assay, the EIA had an initial sensitivity of 94.3% and a specificity of 99.3%. However, after resolution of six discrepants using another ELISA for toxin A detection the sensitivity, specificity, positive and negative predictive values for the TOX A/B test are as follows: 94.5%; 100%; 100%; 98.8%. The corresponding values for the cytotoxicity assay are: 97%; 100%; 100%; and 99.3%. This test seems to have excellent sensitivity and specificity as compared to an in-house cell culture cytotoxicity assay. It is sensitive enough to use as a stand-alone test for the detection of C. difficile toxin in laboratories that do not have cell culture cytotoxicity testing capability.
将1109份连续收集的腹泻粪便样本用于艰难梭菌病的推定诊断，对TOX A/B检测（美国弗吉尼亚州布莱克斯堡Techlab公司）与细胞培养细胞毒性试验进行了比较。TOX A/B检测是一种微孔板酶免疫测定法，可同时检测毒素A和毒素B。本研究采用的检测程序大约需要1.5小时完成。细胞培养细胞毒性试验采用成纤维细胞系，以微孔板形式在4小时、24小时和48小时读取结果。在1109份样本中，有194份通过“金标准”细胞毒性试验呈阳性，而189份通过酶免疫测定呈阳性。两种检测方法的一致性为98.5%。与细胞毒性试验相比，酶免疫测定的初始灵敏度为94.3%，特异性为99.3%。然而，在使用另一种用于毒素A检测的酶联免疫吸附测定法解决了6个不一致的结果后，TOX A/B检测的灵敏度、特异性、阳性预测值和阴性预测值如下：94.5%；100%；100%；98.8%。细胞毒性试验的相应值为：97%；100%；100%；99.3%。与内部细胞培养细胞毒性试验相比，该检测似乎具有出色的灵敏度和特异性。它足够灵敏，可在没有细胞培养细胞毒性检测能力的实验室中作为检测艰难梭菌毒素的独立检测方法使用。
