Xpert MTB/RIF技术辅助诊断耐多药肺结核的价值分析

Value and analysis of Xpert MTB/RIF technology in the auxiliary diagnosis of multiple drug resistant pulmonary tuberculosis

目的研究Xpert MTB/RIF检测方法在涂阳痰标本中检测MTB和RIF耐药性,在基层涂阳耐多药肺结核诊断中的应用价值。方法连续纳入203例涂阳患者的痰标本,对同一份痰标本进行涂片抗酸染色、MGIT320液体培养、液体药敏试验、胶体金试验、基因芯片菌种鉴定和Xpert MTB/RIF检测。结果 MGIT320和Xpert MTB/RIF与痰涂片镜检阳性符合率分别为93.60%和94.09%;MGIT320和Xpert MTB/RIF结果符合率为88.67%;以液体培养胶体金法初步菌型鉴定为金标准,Xpert MTB/RIF检测结核分枝杆菌灵敏度为98.88%、特异度为81.82%;以MGIT320液体药敏结果为金标准,Xpert MTB/RIF检测利福平耐药的灵敏度为95.65%、特异度为100.00%,2种方法一致性好(kappa=0.975,P<0.05)。结论 MGIT320和Xpert MTB/RIF与痰涂片镜检阳性符合率高;Xpert MTB/RIF和MGIT320检测利福平耐药一致性好,在2 h内出结果,硬件设施要求低,有助于基层实验室更快,更有效地辅助诊断涂阳耐多药肺结核。

Objective To detect the MTB and RIF resistance in smear positive sputum specimens with Xpert MTB / RIF detection method and its application value in the diagnosis of smear positive multi drug resistant pulmonary tuberculosis. Methods Sputum samples from 203 smear positive patients were enrolled,and smear acid fast staining,MGIT320 liquid culture,liquid drug sensitivity test,colloidal gold test,identification of gene chip,and Xpert MTB / RIF detection were performed on the same sputum sample. Results The coincidence rate of MGIT320 and Xpert MTB / RIF with sputum smear microscopy was respectively93. 60% and 94. 09%; the result coincidence rate of MGIT320 and Xpert MTB / RIF was 88. 67%; and,the preliminary bacterial identification by liquid culture colloidal gold method was appraised as gold standard,the sensitivity of Xpert MTB / RIF in the detection of Mycobacterium tuberculosis was 98. 88%,with the specificity of 81. 82%; taking the liquid drug sensitivity results of MGIT320 as gold standard,it is found that the sensitivity of Xpert MTB / RIF in the detection of rifampin resistance was95. 65%,with the specificity of 100. 00%,and the 2 methods obtained good coincidence（ kappa = 0. 975,and P 0. 05）.Conclusion The coincidence of MGIT320 and Xpert MTB / RIF with sputum smear microscopy positive is high; the consistency of Xpert MTB / RIF and MGIT320 in the detection of rifampin resistance is good; the results can be achieved in 2 hours,and the requirement of hardware facility for detection is quite low,which is helpful for the primary laboratory to be faster and more effective in the auxiliary diagnosis of smear positive multi drug resistant pulmonary tuberculosis.