Sun Jun-Ren, Lee Shih-Yi, Perng Cherng-Lih, Lu Jang-Jih
Division of Clinical Pathology, Department of Pathology, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan.
J Formos Med Assoc. 2009 Feb;108(2):119-25. doi: 10.1016/S0929-6646(09)60042-5.
BACKGROUND/PURPOSE: Diagnosis of tuberculosis is challenging because the current methods are time-consuming and laborious. We have developed a method combining the Bactec MGIT 960 rapid culture system with the IS6110-based PCR for rapid diagnosis of tuberculosis.
A total of 1745 samples from 712 patients treated at the Tri-Service General Hospital, Taipei, Taiwan between June and August 2005 were tested. An aliquot of positive Bactec MGIT 960 culture fluids was Kinyoun stained, and the samples positive for Kinyoun staining were directly assayed by the IS6110-based PCR. The same samples were also examined by the conventional methods for identification of Mycobacterium tuberculosis complex.
One hundred and four samples from 62 patients were positive according to the Bactec MGIT 960 system. Among these, 59 (56.7%) were positive and 45 (43.3%) were negative according to the IS6110-based PCR. Compared with the conventional identification methods, the IS6110-based PCR assay correctly identified all 59 M. tuberculosis isolates and gave negative results for all nontuberculosis mycobacteria. The mean turnaround time for M. tuberculosis identification by this combined method was 6.41 days for smear-positive and 14.33 days for smear-negative specimens. The sensitivity of the IS6110-based PCR assay was determined to be 5 cells or 0.1 pg of mycobacterial DNA.
The combined use of the automated Bactec MGIT 960 system and the IS6110-based PCR assay is sensitive and rapid for the detection of M. tuberculosis complex, and we recommend that this method be used routinely for identification of mycobacteria in clinical laboratories.
背景/目的：结核病的诊断具有挑战性，因为目前的方法既耗时又费力。我们开发了一种将Bactec MGIT 960快速培养系统与基于IS6110的聚合酶链反应（PCR）相结合的方法，用于结核病的快速诊断。
对2005年6月至8月间在台湾台北三军总医院接受治疗的712例患者的1745份样本进行检测。取Bactec MGIT 960培养阳性的培养液进行金胺O染色，对金胺O染色阳性的样本直接采用基于IS6110的PCR检测。同样的样本也采用传统方法进行结核分枝杆菌复合群鉴定。
根据Bactec MGIT 960系统，62例患者的104份样本呈阳性。其中，根据基于IS6110的PCR检测，59份（56.7%）呈阳性，45份（43.3%）呈阴性。与传统鉴定方法相比，基于IS6110的PCR检测正确鉴定了所有59株结核分枝杆菌，对所有非结核分枝杆菌均给出阴性结果。该联合方法鉴定结核分枝杆菌的平均周转时间，涂片阳性标本为6.41天，涂片阴性标本为14.33天。基于IS6110的PCR检测的灵敏度确定为5个细胞或0.1 pg分枝杆菌DNA。
自动Bactec MGIT 960系统与基于IS6110的PCR检测联合使用，对结核分枝杆菌复合群的检测灵敏且快速，我们建议临床实验室常规使用该方法鉴定分枝杆菌。
