894株结核分枝杆菌对一线抗结核药物的耐药情况分析

收集2016年1月至2018年3月吉林省9个市(州)894例肺结核患者痰标本中的结核分枝杆菌临床分离株进行分析。并采用比例法药物敏感性试验(简称“药敏试验”)对全部结核分枝杆菌菌株进行利福平(RFP)、异烟肼(INH)、链霉素(Sm)和乙胺丁醇(EMB)4种一线抗结核药物的药敏试验。结果显示,894株结核分枝杆菌对一线抗结核药物敏感者有546株(61.07%),对一线抗结核药物耐药者有348株(38.93%);其中初治患者的耐药率为36.30%(265/730),低于复治患者的耐药率(50.61%,83/164),差异有统计学意义(χ ²=11.53,P=0.001)。全部患者的总耐多药率为10.07%(90/894),复治患者耐多药率(20.73%,34/164)高于初治患者(7.67%,56/730),差异有统计学意义(χ ²=25.23,P=0.001)。全部患者对一线抗结核药物的耐药率顺位为Sm(25.95%,232/894)>INH(18.57%,166/894)>RFP(17.23%,154/894)>EMB(9.73%,87/894)。吉林省肺结核患者对一线抗结核药物耐药率较高,尤其是复治患者;耐药结核病防治形势依然严峻,需加强结核病的防控工作。     

Resistance of Mycobacterium tuberculosis to four first-line anti-tuberculosis drugs in Japan, 1997.

SETTING: Five years after the last survey of drug-resistant tuberculosis in Japan, a nationwide survey was conducted by the Tuberculosis Research Committee. OBJECTIVE: To determine the prevalence of and risk factors for resistance to four first-line anti-tuberculosis drugs. DESIGN: Cultures were obtained from patients hospitalized at 78 hospitals in different districts of Japan throughout a 6-month period, 1 June-30 November 1997. Drug susceptibility testing was carried out at the Research Institute of Tuberculosis, Tokyo, one of the supranational reference laboratories of the WHO/IUATLD global project. RESULTS AND CONCLUSION: Among patients with no prior treatment, resistance to any of the four drugs was found in 10.3%, and the prevalence of primary multidrug resistance (MDR) was 0.8%. The prevalence of acquired resistance was 42.4% for any of the four drugs and 19.7% for MDR, indicating a high prevalence rate compared with those reported in the WHO/IUATLD global project. About 73% of resistant isolates from new cases were resistant to one drug, while 64.3% of resistant isolates from the re-treatment cases were resistant to two or more drugs (P < 0.0001). No significant differences in resistance rates by sex, age group, nationality, district, and/or accompanying diseases were observed in any of the new or re-treatment cases. Other factors associated with the high prevalence in re-treatment cases remain to be determined.     

手工MGIT法检测结核分枝杆菌异烟肼和利福平耐药的效果评价

目的 评价MGIT手工荧光判读法在检测结核分枝杆菌耐药的基层应用价值。方法 以常规L-J比例法为参照方法,比较分析手工荧光MGIT液体药敏法检测300株临床结核分离株异烟肼和利福平药敏效果。结果 手工MGIT液体药敏法检测异烟肼和利福平灵敏度和特异度分别为94.7%和92.6%、95.6%和98.8%。两种药敏方法的异烟肼符合率95.7%,利福平符合率97.7%,两种方法检测异烟肼和利福平敏感性的差异无统计学意义(P>0.05)。液体药敏阳性报告时间平均7.6 d,比传统比例法报告时间提前20.4 d。结论 手工MGIT液体药敏法与常规L-J比例法检测异烟肼和利福平敏感性结果一致性高,能快速、准确检测结核分枝杆菌异烟肼和利福平耐药,适合基层推广。     

In-vitro susceptibility of Mycobacterium avium complex to isoniazid and ethionamide

In this study, it was investigated whether or not Mycobacterium avium complex strains were inhibited by such low concentrations of isoniazid and ethionamide as possible in blood. The inhibitory concentrations were determined by the "Actual Count" method (Tsukamura, M.: Japan J. Tuberc. 12: 46-54, 1964), in which the inhibitory concentration was measured as a concentration that can inhibit the growth of 'countable' colony-forming units. The ratio of strains which were inhibited by such low concentrations as 0.2 microgram/ml isoniazid or 5 micrograms/ml ethionamide was 14%. The result suggests that there are some strains in which isoniazid or ethionamide are clinically effective, though their prevalence was low (14%).     

Rapid and simple MTT method for rifampicin and isoniazid susceptibility testing of Mycobacterium tuberculosis.

The MTT method for rifampicin and isoniazid susceptibility testing of Mycobacterium tuberculosis was developed by using bacterial suspension prepared from colonies on solid media. The MTT tube assay in 1 ml Middlebrook 7H9 broth was completed within 4 days for rifampicin (RMP) and within 7 days for isoniazid (INH). When MTT assay results with 279 M. tuberculosis clinical isolates were compared with those of the conventional proportion method on L?wenstein-Jensen medium, high specificity and sensitivity values of 100% and 94.1%, respectively, for RMP susceptibility testing, and 99.5% and 89.2%, respectively, for INH susceptibility testing were obtained. The accuracy of the MTT method for RMP and INH was > 0.97 concordance with the proportion method. The MTT method is simple, inexpensive and rapid. The high level of agreement with the conventional proportion method suggests a potential to rapidly detect drug-resistant M. tuberculosis in developing countries, as only basic microbiological equipment is need.     

耐多药结核病快速诊断试剂盒检测耐药结核分枝杆菌的评价

目的 评价用耐多药结核病快速诊断(GenoType MTBDRplus)试剂盒检测耐利福平、异炳肼MTB的效果.方法 选取75株MTB临床分离株,采用耐多药结核病快速诊断试剂盒检测其中的耐药MTB,评价其敏感度和特异度及可重复性,并与常规的药物敏感性试验方法相比较.结果 耐多药结核病快速诊断试剂盒对上海地区的MTB临床分离株中耐利福平和耐异烟肼菌株的敏感度分别为98.0%和86.5%,对敏感菌株的特异度为100%.而在重复性试验中,耐多药结核病快速诊断试剂盒多次结果完全一致,重复性达到100%.结论 耐多药结核病快速诊断作为快速检测耐药MTB的试剂盒,对耐利福平和耐异烟肼菌株具有较高的敏感度和特异度,在上海地区有较好的应用前景.     

Host determinants of susceptibility to Mycobacterium tuberculosis

Susceptibility to tuberculosis is determined by a number of host factors and may vary according to characteristics of the infecting strain. Native resistance is probably mediated via the macrophage and is under genetic control. Other factors that contribute to native resistance are nutrition, associated disease states, age, and sex. Acquired resistance is mediated via macrophages and controlled by T-helper cells. The ability of an activated macrophage to phagocytize and kill virulent tubercle bacilli is influenced by the function and number of T-helper cells. The macrophages are affected by concurrent disease states and immunosuppressive drugs. Macrophages provide local immunity, once activated, and T-helper lymphocytes provide the long-term systemic immunity.     

首次证实结核分枝杆菌发生了对异烟肼的复敏

背景：结核分枝杆菌耐药株在全世界范围内呈现播散的趋势,对全球的公共卫生造成了严重威胁。然而,关于耐药突变在菌群中是否永久存在,或者说在没有药物压力下耐药突变是否会发生逆转,目前还没有定论。目的：为证实在1位耐多药结核（TB）病人身上发生了异烟肼（INH）复敏的情况,并研究与之相关的细菌生存能力的降低。设计：应用基因型分析和表型分析研究来自1位肺结核病人的耐异烟肼分离株发生异烟肼复敏的情况。应用全敏感株重新构建了与复敏发生前katG突变一致的细菌模型（H37 RvkatG：katGW300G）,并测试了此菌株对INH的敏感性和对氧化压力的反应。结果：基因分型和药物敏感性试验显示在不应用INH治疗的情况下,同一基因型的结核分枝杆菌菌株发生了从INH耐药向INH敏感的转变。对这种现象的基因型基础也进行了分析,发现katG的第300位密码子发生了改变,从GGG（甘氨酸,G）回复到野生型密码子TGG（色氨酸,w）。菌株H37RvhatG：：katGW300G对INH耐药,但是也同时显示出对氧化压力的反应性差。结论：此次研究证实,在没有INH药物压力的情况下,一些INH耐药突变株会转变成药物敏感的表型。此次发现对于研究异烟肼耐药的菌株和临床使用INH的时限可能有广泛的意义。     

Blood agar for susceptibility testing of Mycobacterium tuberculosis against first-line drugs.

OBJECTIVE: To evaluate the performance of blood agar for the susceptibility testing of 50 Mycobacterium tuberculosis clinical isolates against isoniazid (INH), rifampicin (RMP), streptomycin (SM) and ethambutol (EMB). DESIGN: The activity of the drugs was determined by the proportion method on blood agar instead of Middlebrook 7H10 agar according to Clinical Laboratory Standard Institute recommendations. The final concentrations of INH, RMP, SM and EMB were 0.2 microg/ml, 1 microg/ ml, 2 microg/ml and 5 microg/ml, respectively. RESULTS: The results were compared with the radiometric proportion method as the reference, and the agreements were determined as 100% for INH and RMP, 92% for SM and 96% for EMB. The specificity, sensitivity, positive predictive value and negative predictive value were 90.4% and 97.5%, 100% and 90%, 66.6% and 90% and 100% and 97.5% for SM and EMB, respectively, while these values were 100% for INH and RMP. The results of susceptibility testing were obtained on the 14th day of incubation. CONCLUSION: According to this preliminary study, our results suggest that blood agar can be used as an alternative medium for the susceptibility testing of M. tuberculosis strains against INH, RMP, SM and EMB in resource-limited countries. However, further studies are needed before implementating the method in diagnostic laboratories.     

结核杆菌异烟肼耐药的分子机制

在抗结核治疗策略中,异烟肼是最重要的一线药物.在过去50年的抗结核治疗中,异烟肼发挥了非常重要的作用,而耐异烟肼结核菌的出现使这种效果减弱.本文从异烟肼的抗结核机制人手,对异烟肼耐药的分子机制作一综述.     

实时荧光定量PCR法分析结核分枝杆菌对异烟肼耐药的分析

目的利用实时荧光定量PCR技术快速检测异烟肼耐药结核分枝杆菌。方法收集到医院就诊的结核病疑似患者痰液样本,提取痰液样本的总DNA,利用实时荧光定量PCR(Real-time PCR)技术对结核分枝杆菌感染进行快速筛查,并与传统药敏试验进行比较,对两者的灵敏度、特异性、一致性进行比较分析。结果检测346例结核病人临床分离培养样本,药敏试验检出257例异烟肼敏感标本,101例异烟肼耐药标本;实时荧光定量PCR法共检测出异烟肼敏感和耐药标本225例98例,灵敏度为86.64%,特异性为93.92%,一致率为93.12%。结论跟传统药物敏感性实验相比,实时荧光定量PCR法检测速度快速、特异性强、灵敏度较高,可用于结核分枝杆菌耐异烟肼突变的快速检测,适于耐多药结核病的快速筛查。     

应用基因芯片方法检测结核分枝杆菌利福平和异烟肼的耐药性

目的 应用基因芯片方法检测结核分枝杆菌(Mycobacterium tuberculosis,Mtb)对利福平和异烟肼的耐受性,评价其临床应用价值。方法 应用聚合酶链反应（polymerase chain reaction,PCR）扩增-基因芯片杂交的方法检测经常规药敏实验证实的30株Mtb利福平和异烟肼敏感株和50株耐利福平和异烟肼分离株的rpoB基因及katG和inhA基因突变,同时以PCR-直接测序法为对照。结果 应用PCR-基因芯片与基因测序方法检测30株Mtb利福平敏感株rpoB基因和异烟肼敏感株katG基因和inhA基因均为野生型。50株Mtb利福平耐药株中,PCR-基因芯片与基因测序分析3株rpoB基因均为野生型,41株均为突变型;6株PCR-基因芯片与基因测序结果不一致。50株Mtb异烟肼耐药株中,PCR-基因芯片与基因测序分析16株katG基因和30株inhA基因均为野生型,31株katG基因均为315位密码子突变,7株inhA基因均为15位突变型,其中2株为katG和inhA双重突变;3株katG和13株inhA PCR-基因芯片与基因测序结果不一致。结论 应用PCR-基因芯片方法可快速、有效地检出大多数Mtb耐多药分离株,指导临床用药。     

结核分枝杆菌对氨基甙和喹诺酮类药物耐药性调查

目的分析了解近年来结核病患者对氨基甙和喹诺酮类药物的耐药情况。方法采用绝对浓度间接法进行了三种常用抗结核药物的敏感试验。结果每种抗结核药物的年耐药发生率呈波浪式变化,但是总的发生率却是呈现逐步上升趋势。结论目前对于丁胺卡那霉素,卷曲霉素,左氧氟沙星这类药物的耐药率仍处于较低水平,我们在临床工作中必须规范用药,以避免或减少广泛耐多药的产生。