实时定量聚合酶链反应技术在鉴别结节病与增殖性结核病中的应用

目的利用实时定量聚合酶链反应（PCR）方法检测结节病和结核病病理组织中结核分枝杆菌DNA，以探讨结核分枝杆菌在结节病发病中的作用及本方法在结节病与增殖性结核病鉴别中的应用价值。方法以上海市肺科医院1998年1月至2003年12月住院患者76例为研究对象，其中结核病组30例、结节病组31例和正常对照组（其他疾病）15例，利用定量PCR检测用石蜡包埋的淋巴结或肺组织中结核分枝杆菌DNA，并以胎鼠肺组织作为阴性对照。结果结核病组结核分枝杆菌DNA检出的阳性率（30／30）明显高于结节病组（6／31）和正常对照组（2／15），结节病组与正常对照组结核分枝杆菌DNA检出的阳性率无明显差别。结核病组结核分枝杆菌DNA检出的绝对和相对拷贝数明显高于结节病组和正常对照组，结节病组与正常对照组无明显差别，而胎鼠肺组织中未检出结核分枝杆菌DNA。结论本研究结果不支持结核分枝杆菌感染与结节病的相关性。实时定量PCR法检测石蜡包埋病理组织中结核分枝杆菌DNA可作为鉴别增殖性结核和结节病的方法之一。

Application of quantitative polymerase chain reaction in the differentiation of sarcoidosis and proliferative tuberculosis

OBJECTIVE: To evaluate the role of mycobacterial infection in the pathogenesis of sarcoidosis by examination of mycobacterial DNA in tissue samples of sarcoidosis and tuberculosis, and to examine the value of quantitative real-time polymerase chain reaction (PCR) in the differentiation of the two diseases. METHODS: Mycobacterium tuberculosis DNA was measured by quantitative real-time PCR from formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes and lung tissues from 31 patients with sarcoidosis, 30 patients with tuberculosis and 15 patients with other diseases (as the control samples) in Shanghai Pulmonary Hospital from January 1998 to December 2003. Lung tissues from 15 normal embryonic mice served as the negative control. RESULTS: The positive rate of mycobacterial DNA in the tuberculosis samples (30/30) was higher than that of the sarcodosis samples (6/31) and of the control samples (2/15). The difference between sarcoidosis and normal samples showed no statistical significance. The absolute and relative copies of mycobacterial DNA in the tuberculosis samples were significantly higher than those in the sarcoidosis and the control samples; while there was no statistical difference between the sarcoidosis and the control samples. There was no positive result in the lung tissues of the embryonic mice. CONCLUSIONS: The results do not show any relationship between mycobacterial infection and sarcoidosis. Quantitative PCR may be a reliable method for the differentiation of sarcodosis from tuberculosis.