Washington State Public Health Laboratories, Shoreline, Washington, USA.
J Clin Microbiol. 2012 Feb;50(2):326-36. doi: 10.1128/JCM.05570-11. Epub 2011 Dec 7.
Tuberculosis (TB) remains a significant global health problem for which rapid diagnosis is critical to both treatment and control. This report describes a multiplex PCR method, the Mycobacterial IDentification and Drug Resistance Screen (MID-DRS) assay, which allows identification of members of the Mycobacterium tuberculosis complex (MTBC) and the simultaneous amplification of targets for sequencing-based drug resistance screening of rifampin-resistant (rifampin(r)), isoniazid(r), and pyrazinamide(r) TB. Additionally, the same multiplex reaction amplifies a specific 16S rRNA gene target for rapid identification of M. avium complex (MAC) and a region of the heat shock protein 65 gene (hsp65) for further DNA sequencing-based confirmation or identification of other mycobacterial species. Comparison of preliminary results generated with MID-DRS versus culture-based methods for a total of 188 bacterial isolates demonstrated MID-DRS sensitivity and specificity as 100% and 96.8% for MTBC identification; 100% and 98.3% for MAC identification; 97.4% and 98.7% for rifampin(r) TB identification; 60.6% and 100% for isoniazid(r) TB identification; and 75.0% and 98.1% for pyrazinamide(r) TB identification. The performance of the MID-DRS was also tested on acid-fast-bacterium (AFB)-positive clinical specimens, resulting in sensitivity and specificity of 100% and 78.6% for detection of MTBC and 100% and 97.8% for detection of MAC. In conclusion, use of the MID-DRS reduces the time necessary for initial identification and drug resistance screening of TB specimens to as little as 2 days. Since all targets needed for completing the assay are included in a single PCR amplification step, assay costs, preparation time, and risks due to user errors are also reduced.
结核病(TB)仍然是一个严重的全球健康问题,快速诊断对于治疗和控制都至关重要。本报告描述了一种多重 PCR 方法,即分枝杆菌鉴定和耐药筛查(MID-DRS)检测,该方法可鉴定结核分枝杆菌复合群(MTBC)成员,并同时扩增利福平耐药(利福平(r))、异烟肼(r)和吡嗪酰胺(r)结核的测序耐药筛查靶标。此外,同一多重反应还扩增了用于快速鉴定鸟分枝杆菌复合群(MAC)的特定 16S rRNA 基因靶标,以及热休克蛋白 65 基因(hsp65)的一个区域,用于进一步基于 DNA 测序的确认或鉴定其他分枝杆菌种。MID-DRS 与总共 188 个细菌分离株的基于培养的方法的初步结果比较表明,MID-DRS 对 MTBC 鉴定的敏感性和特异性为 100%和 96.8%;MAC 鉴定为 100%和 98.3%;利福平(r)TB 鉴定为 97.4%和 98.7%;异烟肼(r)TB 鉴定为 97.4%和 98.7%;异烟肼(r)TB 鉴定为 60.6%和 100%;吡嗪酰胺(r)TB 鉴定为 75.0%和 98.1%。MID-DRS 的性能也在抗酸杆菌(AFB)阳性临床标本上进行了测试,结果显示 MTBC 的检测敏感性和特异性为 100%和 78.6%,MAC 的检测敏感性和特异性为 100%和 97.8%。总之,使用 MID-DRS 将初始 TB 标本的鉴定和耐药筛查所需的时间缩短至最短 2 天。由于完成检测所需的所有靶标都包含在单个 PCR 扩增步骤中,因此还降低了检测成本、准备时间和由于用户错误而导致的风险。