Evaluation of a bacteriophage-based assay (phage amplified biologically assay) as a rapid screen for resistance to isoniazid, ethambutol, streptomycin, pyrazinamide, and ciprofloxacin among clinical isolates of Mycobacterium tuberculosis
Evaluation of a bacteriophage-based assay (phage amplified biologically assay) as a rapid screen for resistance to isoniazid, ethambutol, streptomycin, pyrazinamide, and ciprofloxacin among clinical isolates of Mycobacterium tuberculosis
复制标题
DOI：
10.1128/jcm.37.11.3528-3532.1999
复制
发表时间：
1999-11-01
影响因子：
9.4
通讯作者：
Drobniewski, FA
中科院分区：
文献类型：
--
作者：
Eltringham, IJ;Wilson, SM;Drobniewski, FA
用于检测结核分枝杆菌中与利福平耐药性相关的突变的快速分子测定是商业上可获得的，然而，它们复杂且昂贵，并且预测值为90%至95%。其他药物的分子检测对耐药性的预测性较低。理想情况下，基于表型标记物的测定应用于敏感性测试，但这些可能需要数周才能完成。我们以前描述了一种快速的表型测定，噬菌体生物扩增（PhaB）测定，用于快速测定结核分枝杆菌临床分离株对利福平和异烟肼的敏感性。在这项研究中，我们扩大了测定乙胺丁醇，吡嗪酰胺，链霉素，环丙沙星的研究。在优化抗生素浓度和孵育条件后，将该测定法应用于每种药物，共157株分离株。PhaB测定和耐药率方法的结果之间的相关性为94%，异烟肼，96%，链霉素，100%，环丙沙星，乙胺丁醇，和87%，吡嗪酰胺，环丙沙星，乙胺丁醇，和吡嗪酰胺，显着更好的相关性时，发现90%的减少空斑计数作为截止。PhaB检测的周转时间为2至3天，而耐药率方法为10天。我们相信，这种低成本的检测方法可能具有广泛的适用性，快速筛选耐药性的M。结核病分离株，特别是在发展中国家。
Rapid molecular assays for the detection of mutations associated with rifampin resistance in Mycobacterium tuberculosis are commercially available, However, they are complex and expensive and have predictive values of 90 to 95%. Molecular assays for other drugs are less predictive of resistance. Ideally, assays based on phenotypic markers should be used for susceptibility testing, but these can take weeks to complete. We previously described a rapid phenotypic assay, the phage amplified biologically (PhaB) assay, for the rapid determination of rifampin and isoniazid susceptibility in clinical isolates of M, tuberculosis. In this study, we extended the assay to the study of ethambutol, pyrazinamide, streptomycin, and ciprofloxacin. After the optimization of antibiotic concentrations and incubation conditions, the assay was applied to each drug for a total of 157 isolates. The correlations between the results of the PhaB assay and the resistance ratio method were 94% for isoniazid, 96% for streptomycin, 100% for ciprofloxacin, 88% for ethambutol, and 87% for pyrazinamide, For ciprofloxacin, ethambutol, and pyrazinamide, significantly better correlations were found when a 90% reduction in plaque count was used as the cutoff. Turnaround times for the PhaB assay were 2 to 3 days, compared with 10 days for the resistance ratio method. We believe that this low-cost assay may have widespread applicability for the rapid screening of drug resistance in M. tuberculosis isolates, especially in developing countries.