Xpert MTB/RIF与微量MIC快速检测利福平异质性耐药的分析

Value analysis of rapid detect rifampicin heterogeneity drug-resistant mycobacterium tuberculosis by Xpert MTB/RIF with trace MIC assay

目的探讨Xpert MTB/RIF与微量液体培养及药敏试验(微量MIC)在快速检测痰标本中利福平(RFP)异质性耐药结核菌(MTB)价值。方法对2016年8月~2020年02月间在南通市第六人民医院就诊466例肺结核患者涂阳痰标本分别进行Xpert MTB/RIF检测、微量MIC、改良罗氏(L-J)培养及比例法药敏试验,对三种方法的检测结果进行分析。结果Xpert MTB/RIF检出94例痰标本中MTB存在rpoB基因突变(RFP耐药决定区基因);微量MIC检测到76例痰标本中MTB对RFP耐药;L-J培养及比例法药敏试验结果鉴定为MTB且耐RFP痰标本77例。以比例法药敏试验结果为判断标准,Xpert MTB/RIF检测结果同比例法药敏试验结果一致性好(Kappa=0.85),两组比较差异无统计学意义(χ^(2)=1.17,P>0.05);微量MIC检测结果同比例法药敏试验结果基本一致(Kappa=0.99),两组比较差异无统计学意义(χ^(2)=0.25,P>0.05)。比例法药敏试验结果和微量MIC药敏报告时间分别为52.5天和17.5天,差异有统计学意义(t=4.64,P<0.05)。结论Xpert MTB/RIF检测RFP耐药具有重要筛查价值,微量MIC药敏结果与比例法药敏高度一致、但药敏报告时间明显缩短。利用Xpert MTB/RIF与微量MIC检测效能并对差异性结果进行分析,可能对快速精准检测痰标本中RFP异质性耐药MTB具有重要参考价值。

Objective To assess the value of rapid detecting rifampicin(RFP)heterogeneity drug-resistance of mycobacterium tuberculosis(MTB)in sputum specimens by Xpert MTB/RIF with trace liquid culture and drug sensitive test assay(trace MIC).Methods 466 cases sputum smear-positive specimen of pulmonary tuberculosis patients from August 2016 to February 2020 in Nantong sixth people′s hospital were detected by Lowenstein-Jensin(L-J)culture and proportion method drug susceptibility respectively,trace MIC,and Xpert MTB/RIF methods.The testing results of the three methods were analyzed.Results 94 cases of rpoB gene(RFP drug-resistant genes that determine area)mutation MTB in sputum specimen were detected by Xpert MTB/RIF.76 cases of RFP drug-resistant MTB in sputum specimens were identified by trace MIC,which Xpert MTB/RIF report suggested that drug resistance.77 cases of RFP drug-resistant MTB in sputum specimens were identified by L-J culture and proportion method drug susceptibility.Taking the results of proportion method drug susceptibility test as the judgment standard,Xpert MTB/RIF had good consistency(Kappa=0.85),and there was no statistically significant difference(χ^(2)=1.17,P>0.05).Trace MIC was basically identical with proportion method drug susceptibility(Kappa=0.99),and there was no statistically significant difference(χ^(2)=0.25,P>0.05).The drug susceptibility report times of proportion method drug susceptibility and trace MIC assay were 52.5d and 17.5d respectively(t=4.64,P<0.05).Conclusion It has screening value of RFP drug-resistant results which through MTB/RIF detection.Trace MIC drug susceptibility results is highly consistent with proportion method drug susceptibility test,but the drug susceptibility reports time time is significantly shortened.Using detection efficiency of MTB/RIF with trace MIC and analyzing the results of the differences,it may have important reference value of rapid and precise detect rifampicin heterogeneity drug-resistant mycobacterium tuberculosis in sputum specimens.