显微镜观察药物敏感性检测在分枝杆菌分离培养和药物敏感性测定中的应用研究

目的评价显微镜观察药物敏感性检测(MODS,microscopic observation drug suscepti-bility assay)方法用于分枝杆菌分离培养和直接药物敏感性测定的应用前景。方法应用MODS方法对113例涂片镜检阳性患者痰标本进行分离培养,同时进行异烟肼、利福平、链霉素、乙胺丁醇4个药物的直接药物敏感性测定,以罗氏法分离培养和间接绝对浓度法作为对照,对分离培养和药敏结果进行对比分析,并通过DNA序列分析对不一致药敏结果进一步验证。结果 MODS与罗氏法分离培养的阳性率均为83.2%,污染率分别为0%和2.7%,两方面差异无统计学意义,两者的符合率为93.6%(kappa值:0.75),培养的敏感性、特异性分别为95.7%、81.3%。MODS的分离培养中位数时间为10 d(第95百分位数为21.5 d),罗氏分离培养的中位数时间为25 d(第95百分位数为39.3d)。MODS与间接绝对浓度法的耐药株检出率分别为49.5%、47.8%,符合率为95.5%(kappa值:0.91)差异无统计学意义,MODS检测的敏感性、特异性分别为97.7%、93.3%。MODS对结核分枝杆菌检测的敏感性、特异性、符合率分别为异烟肼(100%、84.5%、89.8%);利福平(100%、100%、100%);链霉素(94.6%、98.0%、96.6%);乙胺丁醇(100%、73.8%、75.0%)。对于利福平、链霉素的药物敏感性检测两种方法有相当高的一致性,而对异烟肼、乙胺丁醇的检测一致性较低。结论 MODS方法是一种操作简单、成本低廉、快速、敏感的诊断和药物敏感性检测方法。适合发展中国家和经济欠发达地区,在我国结核病防控工作中,具有广泛的应用前景。

Research on mycobacteria culture and drug sensitivity assay with microscopic observation method

Objective To assess the value of microscopic observation method （MOM） on mycobacteria culture and drug sensitivity assay. Methods The smear-positive sputum specimens were cultured and directly determined the drug-susceptibility test on isoniazid（INH）, rifampicin（RFP）, streptomycin（SM） and ethamhutol （EMB）with MOM, compared with conventional culture on LSwenstein-Jensen（L-J） medium and drug susceptibility testing using the absolute concentration method. The inconsistent results were further detected with DNA suquencing. Results The positive rates of MOM and conventional culture were both 83.2%. Their contaminative rate were 0~ and 2.7% respectively, which there were no significant difference. Their coincidence rate was 93.6% （kappa value： 0.75）. The sensitivity and specificity of MOM were 95.7% and 81.3% respectively. The median time of culture positivity for MOM was 10 days and LJ was 25 days. The drug-resistant rate of MOM and indirect absolute concentration were 49.5% and 47.8% respectively,which has no statistical difference. Their consistent rate was 95.5% （kappa value： 0. 91）. The sensitivity and specificity of MOM for the drug resistance were 97.7% and 93.3% respectively. The sensitivity, specificity and coincidence of MOM for INH resistance were 100%, 84.5%, 89.8%,RFP were 100%, 100%, 100%,SM were 94.6%, 98.0%, 96.6%,EMB were 100%, 73.8%, 75.0%, respectively. The coincidence for RFP and SM resistance were higher, but INH and EMB were lower. Conclusion MOM is a simple, rapid, sensitive and inexpensive method on the detection and drug susceptibility of mycobaeteria, it is suitable to use in the developing country and undeveloped district.