Pfyffer G E, Kissling P, Wirth R, Weber R
Swiss National Center for Mycobacteria, Department of Medical Microbiology, University of Zurich.
J Clin Microbiol. 1994 Apr;32(4):918-23. doi: 10.1128/jcm.32.4.918-923.1994.
A total of 938 respiratory specimens (633 sputa, 249 bronchial and tracheal aspirates, and 56 bronchoalveolar lavages) from 589 patients were tested for direct detection of Mycobacterium tuberculosis complex by the Gen-Probe amplified Mycobacterium tuberculosis direct test (MTD), and the results were compared with those of the conventional methods of fluorescence microscopy and cultivation (solid and radiometric media). One series of specimens (n = 515) was decontaminated with N-acetyl-L-cysteine (NALC)-NaOH: the other one (n = 423) was decontaminated with sodium dodecyl (lauryl) sulfate (SDS)-NaOH. Of the specimens decontaminated with NALC, 39 were MTD and culture positive, 455 were MTD and culture negative, 18 were MTD positive and culture negative, and 3 were MTD negative and culture positive, indicating a sensitivity of 92.9% and a specificity of 96.2% for the MTD. Of the specimens decontaminated with SDS, 35 were MTD and culture positive, 372 were MTD and culture negative, 15 were MTD positive and culture negative, and 1 was MTD negative and culture positive, indicating a sensitivity of 97.2% and a specificity of 96.1% for the MTD. After resolution of discrepant results by review of the patients' clinical data, the sensitivity of the MTD was 93.9%, the specificity was 97.6%, the positive predictive value was 80.7%, and the negative predictive value was 99.3% for the NALC series; the corresponding values were 97.4, 96.9, 76.0, and 99.7%, respectively, for the SDS series. In conclusion, the MTD is a highly sensitive and specific technique for detecting M. tuberculosis complex within hours in both smear-positive and smear-negative respiratory specimens.
对589例患者的938份呼吸道标本（633份痰液、249份支气管和气管吸出物以及56份支气管肺泡灌洗样本）进行检测，采用Gen-Probe结核分枝杆菌直接扩增试验（MTD）直接检测结核分枝杆菌复合群，并将结果与荧光显微镜检查和培养（固体和放射性培养基）的传统方法结果进行比较。一组标本（n = 515）用N-乙酰-L-半胱氨酸（NALC）-氢氧化钠进行去污处理；另一组（n = 423）用十二烷基硫酸钠（SDS）-氢氧化钠进行去污处理。在经NALC去污处理的标本中，39份MTD和培养均为阳性，455份MTD阳性但培养阴性，18份MTD阳性但培养阴性，3份MTD阴性但培养阳性，表明MTD的敏感性为92.9%，特异性为96.2%。在经SDS去污处理的标本中，35份MTD和培养均为阳性，372份MTD阳性但培养阴性，15份MTD阳性但培养阴性，1份MTD阴性但培养阳性，表明MTD的敏感性为97.2%，特异性为96.1%。通过复查患者临床数据解决结果差异后，对于NALC组，MTD的敏感性为93.9%，特异性为97.6%，阳性预测值为8O.7%，阴性预测值为99.3%；对于SDS组，相应值分别为97.4%、96.9%、76.0%和99.7%。总之，MTD是一种高度敏感和特异的技术，可在数小时内检测涂片阳性和涂片阴性呼吸道标本中的结核分枝杆菌复合群。
