肺泡灌洗液Xpert MTB/RIF检测在涂阴肺结核早期诊断中的应用价值

Detection of Xpert MTB/RIF in bronchoalveolar lavage fluid for diagnosis of smear-negative pulmonary tuberculosis

目的探讨肺泡灌洗液结核杆菌利福平耐药基因(Xpert MTB/RIF)检测在痰涂片阴性(涂阴)肺结核早期诊断中的应用价值。方法选取157例涂阴肺结核患者为观察组,56例排除结核病的患者为对照组,收集肺泡灌洗液进行抗酸染色涂片、分枝杆菌液体培养及Xpert MTB/RIF检测,比较两组患者Xpert MTB/RIF检测阳性率以及观察组3种检测方法的阳性率;并以分枝杆菌液体培养药敏试验结果为金标准,评价Xpert MTB/RIF检测诊断利福平耐药的效能。结果观察组肺泡灌洗液Xpert MTB/RIF检测阳性率为73.9%,明显高于对照组的1.8%(P<0.05)。观察组患者肺泡灌洗液抗酸染色涂片、分枝杆菌液体培养及Xpert MTB/RIF检测阳性率分别为20.4%、38.9%和73.9%;经两两比较,Xpert MTB/RIF检测法>分枝杆菌液体培养法>抗酸染色涂片法,差异均有统计学意义(均P<0.05)。Xpert MTB/RIF检测诊断利福平耐药的灵敏度为100.0%,特异度为98.0%;两者一致性较好。结论肺泡灌洗液Xpert MTB/RIF检测诊断涂阴肺结核的灵敏度和特异度均较高,建议在该类患者中开展肺泡灌洗液Xpert MTB/RIF检测。

Objective To evaluate the detection of Xpert MTB/RIF in bronchoalveolar lavage fluid（BALF） for the early diagnosis of smear-negative pulmonary tuberculosis. Methods The BALF samples were obtained from 157 cases of smear negative pulmonary tuberculosis（study group） and 56 non-pulmonary tuberculosis patients（control group）. The acid fast staining, mycobacterium liquid culture and Xpert MTB/RIF detection in BALF were performed in two groups, and the positive rates of three detection methods in study group were compared. Results The Xpert MTB/RIF positive rate in BALF of study group was significantly higher than that of control group（73.9% vs. 1.8%, P〈0.05）. The positive rates of anti acid staining smear,mycobacterium liquid culture and Xpert MTB/RIF in the study group were 20.4%, 38.9% and 73.9%, respectively（P〈0.05）. With the mycobacterium liquid culture drug sensitivity test as the gold standard, the sensitivity and specificity of Xpert/MTB/RIF for detection of resistance to rifampin was 100.0% and 98.0%, respectively. Conclusion The detection of Xpert MTB/RIF in bronchoalveolar lavage fluid has high sensitivity and specificity in diagnosis of smear-negative pulmonary tuberculosis.