Schafer M P, Fernback J E, Jensen P A
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, OH 45226-1099, USA.
Am Ind Hyg Assoc J. 1998 Aug;59(8):540-6. doi: 10.1080/15428119891010712.
This article presents a novel, qualitative approach for detecting airborne M. tuberculosis. Culturing or sample purification is not required. A DNA diagnostic method involving the polymerase chain reaction (PCR) coupled to an enzymatically generated color reaction was used for direct detection of M. bovis BCG (Bacillus of Calmette-Guérin), a surrogate for pathogenic M. tuberculosis. Fewer than 10 mycobacteria were detected with no culturing using this bioanalytical method. Analysis was completed in 1 to 1.5 days, in contrast to traditional culturing methods requiring a minimum of 2-3 weeks. To evaluate an air sampling method coupled to a PCR bioanalytical method, liquid cultures of the surrogate were aerosolized and collected for PCR analyses using 37-mm filter cassettes containing polytetrafluoroethylene filters. An Andersen six-stage (viable) particle sizing sampler was employed as a reference sampler. Aerosolized BCG impacted onto Andersen agar plates required incubation periods of 6-8 weeks before small colony forming units could be detected and enumerated. Although the BCG mean length of the rod-shaped particles was 8.3 microns, the airborne BCG particles were collected predominantly on the Andersen 4-6 stages, representing aerodynamic diameters 0.7 to 3.3 microns. Approximately 25 mycobacteria were detected without culturing using the PCR-filter cassette method. This approach could be used to detect airborne mycobacterial species of the M. tuberculosis complex and could permit the early detection of contaminated indoor air. Also, the efficacy of environmental controls could be evaluated and monitored. This approach could also be used to study the expulsion of infectious particles from patients and may permit risk assessment in regard to personal respiratory protection.
本文介绍了一种用于检测空气中结核分枝杆菌的新型定性方法。无需进行培养或样本纯化。一种涉及聚合酶链反应（PCR）并结合酶促显色反应的DNA诊断方法被用于直接检测牛型结核分枝杆菌卡介苗（BCG，即卡尔梅特-介朗杆菌），它可作为致病性结核分枝杆菌的替代物。使用这种生物分析方法无需培养即可检测到少于10个分枝杆菌。分析在1至1.5天内完成，而传统培养方法至少需要2至3周。为评估与PCR生物分析方法相结合的空气采样方法，将替代物的液体培养物雾化，并使用含有聚四氟乙烯滤膜的37毫米滤膜盒收集用于PCR分析。使用安德森六级（活菌）颗粒分级采样器作为参考采样器。雾化的卡介苗撞击到安德森琼脂平板上后，需要6至8周的培养期才能检测到并计数小菌落形成单位。尽管杆状颗粒的卡介苗平均长度为8.3微米，但空气中的卡介苗颗粒主要收集在安德森采样器的4至6级，代表空气动力学直径为0.7至3.3微米。使用PCR-滤膜盒方法无需培养即可检测到约25个分枝杆菌。这种方法可用于检测结核分枝杆菌复合群的空气传播分枝杆菌种类，并可实现对室内空气污染的早期检测。此外，还可评估和监测环境控制措施的效果。这种方法还可用于研究患者排出感染性颗粒的情况，并可进行个人呼吸防护方面的风险评估。
