荧光定量PCR在结核分枝杆菌快速诊断中的研究

目的 在痰液标本中,探讨荧光定量PCR技术快速检测结核分枝杆菌应用的诊断价值。方法 选取210例初诊的疑似结核病患者的痰液标本,分别进行痰涂片、MGIT960液体培养以及荧光定量PCR的检测,其中103例标本还进行了Xpert MTB/RIF检测,通过比较来分析荧光定量PCR在检测结核分枝杆菌方面的敏感度和特异性。结果 荧光定量PCR方法从痰液中检出结核分枝杆菌的阳性率高达28%,显著高于痰涂片15.2%的检出率,并且与结核培养的30.9%检出率相接近。以MGIT960液体培养为金标准,荧光定量PCR方法检测痰液标本中的结核分枝杆菌的敏感度和特异度分别为67.7%、 89.7%,阳性预测值和阴性预测值分别为74.6%和86.1%,两者之间差异没有统计学意义。将荧光定量PCR方法与Xpert MTB/RIF诊断方法相比较,分析发现荧光定量PCR方法的敏感度和特异度分别为85.9%、94.9%,阳性预测值和阴性预测值分别为96.5%和80.4%,两者之间差异没有统计学意义。结论 荧光定量PCR方法在检测结核分枝杆菌时具有较好的敏感度和特异度,效果优于传统的痰涂片方法,并且与Xpert MTB/RIF方法具有较好的一致性。荧光定量PCR检测成本较低,且结果准确,在快速检测结核菌方面具有比较好的应用前景。

Study on rapid detection of Mycobacterium tuberculosis with fluorescence quantitative PCR

Objective To explore the diagnostic valueof fluorescent quantitative PCR in the detection of Mycobacterium tuberculosis (MTB) in sputum specimens.Methods A total of 210 suspected tuberculosis (TB) patients who first visited the hospital were recruited, and their sputum samples were collected for sputum smear, MGIT960 liquid culture and fluorescence quantitative PCR detection. Among them, 103 specimens were detected with Xpert MTB/RIF. Through the comparison, the sensitivity and specificity of fluorescence quantitative PCR were analyzed in the detection of MTB.Results The positive rate of the fluorescence quantitative PCR method was 28% in the detection of MTB in sputum, which was significantly higher than that (15.2%) of the sputum smear, and was closed to that (30.9%) of tuberculosis culture. According to the MGIT960 liquid culture as the gold standard, the sensitivity and specificity of fluorescence quantitative PCR in detecting MTB in sputum specimens were 67.7% and 89.7% respectively, the positive predictive value and negative predictive value were 74.6% and 86.1% respectively, and there was no significant difference. Compared to the Xpert MTB/RIF, the sensitivity and specificity of fluorescence quantitative PCR were 85.9% and 94.9% respectively, the positive predictive value and negative predictive value were 96.5% and 80.4% respectively, and there was no significant difference.Conclusion sThe fluorescence quantitative PCR in the detection of MTB has high sensitivity and specificity, which is superior to the traditional sputum smear method, and also has a good consistency with the XpertMTB/RIF method. The cost of fluorescence quantitative PCR is low, and the results are accurate. So, this method has a good application prospect in the rapid detection of MTB.