聚合酶链反应检测肺结核患者外周血单个核细胞中结核分支杆菌DNA

Detection of Mycobacterium tuberculosis DNA in peripheral blood mononuclear cells from patients with pulmonary tuberculosis by polymerase chain reaction technique

目的探讨外周血单个核细胞中结核分支杆菌ＤＮＡ检测在肺结核诊断中的价值。方法采用改良ＴｒｉｔｏｎＸ－１００法分离、制备单个核细胞中模板ＤＮＡ，聚合酶链反应（ＰＣＲ）扩增结核分支杆菌２４０ｂｐ基因片段，同时分析了影响ＰＣＲ结果的有关因素。结果８９例肺结核患者的血标本、８４例肺结核患者的痰标本中，结核分支杆菌ＤＮＡ阳性率分别为７３％和５７％；８４例肺结核患者外周血、痰标本配对检测总阳性率可达８７％。３０例非结核患者的血标本ＰＣＲ阳性率为１０％。结论改良ＴｒｉｔｏｎＸ－１００法处理标本后用ＰＣＲ检测外周血单个核细胞中结核分支杆菌ＤＮＡ具有快速、简便、灵敏、特异等优点，结合痰标本检测，可提高肺结核诊断的敏感性和准确性。

Objective To evaluate the clinical value of detection of Mycobacterium tuberculosis DNA (MTB DNA) in peripheral blood mononuclear cells (PBMC) for diagnosis of pulmonary tuberculosis.Method Polymerase chain reaction (PCR) technique was used to amplify gene of 240 bp DNA fragment prepared by Triton X 100 method, and some factors affecting PCR result were also analysed.Result In blood samples of 89 patients with pulmonary tuberculosis and in sputum samples of 84 patients with pulmonary tuberculosis, the positive rates of PCR were 73% and 57% respectively, and the total positive rate of combinative detection of blood and sputum samples was 87% in 84 pulmonary tuberculosis patients. In 30 non tuberculosis patients, 3 showed MTB DNA positive. Conclusion PCR technique prepared by Triton X 100 method is rapid, simple, specific, and sensitive for detection of MTB DNA in PBMC, and its sensitivity and accuracy could be increased in combination with sputum MTB examination. Detection of MTB DNA in PMBC is of value in diagnosis of pulmonary tuberculosis.