江苏农村地区结核杆菌基因分型及耐药性分析

目的 研究江苏省农村地区分离的结核分枝杆菌基因多态性,从而了解菌株基因型与耐药之间的相关性。方法 采用罗氏培养基分离来自结核病患者痰标本中的结核分枝杆菌,进行间隔区寡核苷酸分型(spacer oligonucleotide typing,Spoligotyping)和比例法进行4种一线抗结核药物的药敏试验。经统计学分析,P<0.05为差异具有统计学意义。结果 547株结核分枝杆菌的Spoligotyping分型结果通过与SpolDB4.0数据库比对后显示,试验菌株被分为18个簇,57个基因型,以北京基因型菌株为主,占79.89%,非北京家族菌株包括T(T1、T2)、U、H、 MANU2、LAM10-CAM和CAS-DELH1等型别,各占11.15%、0.91%、0.37%、0.91%、0.18%和0.18%,以及26个型别(35株菌)为“新型”。药敏试验发现,总耐药率为21.94%,耐多药率为7.68%；单药耐药中,主要以链霉素和异烟肼耐药为主。经χ2检验和Fisher确切概率法分析发现,北京基因型与非北京基因型菌株的耐多药性方面差异具有显著统计学意义。结论 江苏省农村分离的结核分枝杆菌具有明显的基因多态性,北京基因型为主要流行型,并且北京家族菌株与耐多药之间具有一定的相关性。

Genotyping and drug resistance of Mycobacterium tuberculosis strains in rural areas,Jiangsu province

Objective To investigate the gene polymorphisms and the association between the genotyping and drug resistance of clinical Mycobacterium tuberculosis (M. tuberculosis) isolated from the rural areas of Jiangsu province,China. Methods By means of L?wenstein-Jensen (L-J) media,Mycobacteria were isolated from the sputa of the patients with tuberculosis. After M.tuberculosis identified,spacer oligonucleotide typing (Spoligotyping) and drug susceptibility test (DST) for the four first-line antituberculous agents were performed. The results were statistically analysed and P<0.05 means the significant difference. Results By matching the results of Spoligotyping to SpolDB4.0547 database,547 clinical M. tuberculosis isolates were genotyped to 18 clusters and 57 genotypes,in which the predominant group were Beijing family strains,accounting for 79.89%,while non-Beijing genotypes included T1,T2,U,MANU2,LAM and CAS,accounting for 11.15%,0.91%,0.37%,0.91%,0.18% and 0.18%,respectively,and 26 genotypes including 35 isolates were not matched in the SpolDB4,0 database and referred to ′NEW′. DST results showed that the total drug resistance rate was 21.94% and the multidrug resistance rate was 7.68%;among the single drug resistance,the highest was streptomycin and isoniazid. The statistic analysis results by test and Fisher exact probability showed that there was a significant difference in the multidrug resistance between Beijing and non-Beijing family strain. Conclusion There is a significant gene polymorphism in clinical M. tuberculosis strains.The predominant genotype is Beijing family,and there is a correlation between the Beijing genotype and the multidrug resistance in the rural areas of Jiangsu province,China.