支气管肺泡灌洗液行Xpert MTB/RIF检测对涂阴肺结核的诊断价值

Diagnostic value of Xpert MTB/RIF for smear-negative pulmonary tuberculosis using bronchoalveolar lavage fluid

目的评价支气管肺泡灌洗液行Xpert MTB/RIF检测对涂阴肺结核的诊断价值。方法选取从2014年11月至2015年12月徐州市传染病医院收治的3次痰涂片阴性的可疑肺结核患者110例,对所有患者行支气管镜检查进行刷检及收集BALF,进行涂片镜检找抗酸杆菌、结核分枝杆菌培养及Xpert MTB/RIF检测,同时进行诊断。分别以BALF的罗氏培养结果及临床诊断标准作为肺结核诊断的阳性标准,计算Xpert MTB/RIF诊断涂阴肺结核的敏感度、特异度、阳性预测值及阴性预测值。结果以BALF培养阳性结果作为判断肺结核的阳性标准,BALF行Xpert MTB/RIF检测对诊断涂阴肺结核的敏感度、特异度、阳性预测值、阴性预测值分别为100%、97.4%、97.8%、100%。以临床诊断标准为诊断肺结核的阳性标准,BALF行Xpert MTB/RIF检测对诊断涂阴肺结核的敏感度、特异度、阳性预测值、阴性预测值分别为81.9%、97.4%、98.3%、74.0%。以DST结果为金标准,Xpert MTB/RIF检测利福平耐药的敏感度、特异度分别为75.0%、96.0%。结论BALF行Xpert MTB/RIF检测在涂阴肺结核中的敏感度、特异度均较高,且检测快速并能判断是否利福平耐药,对涂阴肺结核的快速诊断及治疗具有较大的应用价值。

Objective To evaluate the diagnostic value of Xpert MTB/RIF for smear-negative pulmonar tu- berculosis using bronchoalveolar lavage fluid. Methods From November 2014 to December 2015 in Xuzhou infec- tious disease hospital, we screened 110 suspected PTB patients with 3 consecutive negative sputum smears, bushed and obtained their BLAF specimen by brochchoscopy. BALF was tested by smear microscopy for acid fast bacilli, my- cobacterium tuberculosis culture and Xpert MTB/RIF assay. The sensitivity, specificity, PPV and NPV for Xpert MTB/RIF test were respectively calculated using culture results and？ clinical diagnostic criteria as reference stand- ard. Results Taking culture positive results as reference standard, the sensitivity, specificity, positive predictive value, negative predictive value of Xpert MTB/RIF for smear-negative PTB testing BALF were 100%, 97.4%, 97. 8%, 100%. Taking clinical diagnostic criteria as reference standard, the sensitivity, specificity, positive predic- tive value, negative predictive value of Xpert MTB/RIF for smear-negative PTB testing BALF were 81.9%, 97.4%, 98. 3%, 74. 0%. With DST results as the gold standard, the sensitivity and specificity of rifampicin resistance using Xpert MTB/RIF assay were 75. 0%, 88. 8% respectively. Conclusion The sensitivity and specificity of Xpert MTB/RIF for smear-negative pulmonary tuberculosis using bronehoalveolar lavage fluid are higher. It can detect quickly and determine whether rifampicin is resistance, and it has great application value of rapid diagnosis and treat- ment for smear-negative tuberculosis.