Loens K, Ieven M, Ursi D, Beck T, Overdijk M, Sillekens P, Goossens H
Department of Medical Microbiology, University of Antwerp UIA, Antwerp, Belgium.
J Clin Microbiol. 2003 Sep;41(9):4448-50. doi: 10.1128/JCM.41.9.4448-4450.2003.
Real-time isothermal nucleic acid sequence-based amplification (RT-NASBA) was applied to the detection of Mycoplasma pneumoniae. In vitro-generated M. pneumoniae RNA was used to assess the sensitivity of the assay. The 95% hit rate was 148 molecules of M. pneumoniae RNA in the amplification and 10(4) molecules of in vitro-generated RNA after nucleic acid extraction. The sensitivity of the RT-NASBA and the conventional NASBA assays corresponded to 5 color-changing units (CCU) of M. pneumoniae. In spiked throat swabs, nasopharyngeal aspirates, bronchoalveolar lavages, and sputum, the sensitivity of both NASBA assays corresponded to 5 to 50 CCU of M. pneumoniae. A total of 17 clinical specimens positive for M. pneumoniae by PCR were also positive by conventional NASBA, but one specimen was negative by RT-NASBA. These results indicate that the sensitivity of detection of M. pneumoniae by RT-NASBA in respiratory samples might be slightly reduced compared to that by conventional NASBA. However, the real-time assay is superior in speed and ease of handling.
实时等温核酸序列扩增技术（RT-NASBA）被应用于肺炎支原体的检测。体外合成的肺炎支原体RNA用于评估该检测方法的灵敏度。扩增时，95%的命中率对应148个肺炎支原体RNA分子，核酸提取后对应10(4)个体外合成的RNA分子。RT-NASBA和传统NASBA检测方法的灵敏度相当于5个肺炎支原体变色单位（CCU）。在加标的咽拭子、鼻咽抽吸物、支气管肺泡灌洗液和痰液中，两种NASBA检测方法的灵敏度相当于5至50个肺炎支原体CCU。通过PCR检测为肺炎支原体阳性的17份临床标本，经传统NASBA检测也呈阳性，但有1份标本经RT-NASBA检测为阴性。这些结果表明，与传统NASBA相比，RT-NASBA在呼吸道样本中检测肺炎支原体的灵敏度可能略有降低。然而，实时检测方法在速度和操作简便性方面更具优势。
