基因芯片和比例法药物敏感性试验检测结核分枝杆菌对利福平和异烟肼耐药性的比较研究

The comparative study of gene chip and ratio drug sensitive test in detecting Mycobacterium tuberculosis resistance to rifampin and isoniazid

目的比较基因芯片和比例法药物敏感性试验在检测结核分枝杆菌(MTB)对利福平(RFP)和异烟肼(INH)耐药性中的应用,探讨快速诊断耐多药结核病(MDR-TB)的方法。方法从改良罗氏培养基上分离的327株菌株,分别用基因芯片检测MTB对RFP和INH耐药相关的rpoB、katG和inhA基因上8个位点的基因突变,从而判断其耐药性;同时用比例法药物敏感性试验检测MTB对RFP和INH耐药性,比较2种方法的符合率。进一步从二者RFP或/和INH结果不符的标本中随机选出16株菌株做DNA序列测定,比较二者与DNA测序的符合率。结果基因芯片和比例法药物敏感性试验检测MTB对RFP耐药性符合率为93.27%,对INH耐药性符合率为95.11%,RFP和INH的总符合率为90.52%;二者对MDR-TB的检出率分别为18.65%和18.96%。基因芯片与DNA测序比较,RFP耐药性符合率为81.25%,INH耐药性符合率为100.00%;比例法药物敏感性试验与DNA测序比较,RFP耐药性符合率为50.00%,INH耐药性符合率为37.50%。结论基因芯片检测MTB对RFP和INH的耐药性较比例法药物敏感性试验有更高的敏感性和特异性,对MDR-TB的快速诊断具有重要临床价值。

Objective To study comparatively the application of gene chip and ratio drug sensitive test in detecting Mycobacterium tuberculosis （MTB） resistance to rifampin （RFP） and isoniazid（INH） , and investigate a rapid method for diagnosing multi-drug resistant tuberculosis （MDR-TB）. Methods After isolating 327 strains from Lowenstein-Jensen, the gene mutation of the 8 sites in rpoB, katG and inhA genes related with MTB resistance to RFP and INH was detected, and the drug resistance was determined. Meanwhile, the ratio drug sensitive test was used to detect MTB resistance to RFP and INH, and the coincidence rates of RFP/INN were compared. Furthermore, 16 strains randomly from the samples which were not consistent with the results of RFP or/and INH were performed DNA sequencing, and then the coincidence rate with the DNA sequencing was compared. Results The coincidence rate of MTB resistance to RFP was 93.27% ,but that to INH was 95.11%. The coincidence rate of MTB resistance to RFP and INH was 90.52%. The detection rates of the 2 methods in detecting MDR-TB were 18.65% and 18.96% , respectively. Comparing the gene chip with DNA sequencing,the coincidence rate of RFP drug resistance was 81.25% , and that of INH drug resistance was 100. 00%. Comparing the ratio drug sensitive test with DNA sequencing, the coincidence rate of RFP drug resistance was 50.00% , and that of INH drug resistance was 37.50%. Conclusions The gene chip in detecting MTB resistance to RFP and INH has high sensitivity and specificity, and has an clinical significance in rapid diagnosis of MDR-TB.