贵州某结核病高发县结核分枝杆菌流行情况的初步研究

Preliminary study on the prevalence of Mycobacteriumtuberculosis in the high incidence county in Guizhou Province,China

目的分析结核病高发县结核分枝杆菌临床分离株及其基因型特征,探索高疫情地区结核菌株流行情况。方法在罗甸县结核病定点医院门诊收集临床分离的分枝杆菌菌株,用PNB生长试验、结核分枝杆菌散在重复单位(VNTR)和RD105缺失基因检测法分别进行菌种、结核分枝杆菌DNA多态性和北京基因型鉴定。结果 80株菌株中非结核分枝杆菌占12.5%,70株结核分枝杆菌中北京家族占42.9%,非北京家族占57.1%。VNTR结果显示,菌株可分为5个基因群,其中I群占15.7%,含11个基因型,Ⅱ群占35.7%,含25个基因型,Ⅲ群占15.7%,含11个基因型,Ⅳ群占30.0%,含21个基因型,Ⅴ群占2.9%,含2个基因型,未见成簇菌株。结论初步证实罗甸县结核分枝杆菌存在基因多态性,Ⅱ群、Ⅳ群为当地主要流行群,同时存在一定比例的非结核分枝杆菌感染。

We analyzed the result of the genotype and other characteristics of Mycobacterium tuberculosis isolated from clinical,and preliminarily studied the epidemic situation of tuberculosis strains in high epidemic area.In Luodian County,M.tuberculosis strains were isolated from pulmonary tuberculosis patients in hospital out-patient department,the strains were analyzed with PNB growth test and molecular methods for identification of Beijing and non-Beijing family isolates,they were typed with mycobacterial interspersed repetitive-unitvariable-number tandem-repeat（VNTR）as well.Nontuberculosis mycobacteria isolates accounted for 12.5%in 80 strains,of 70 M.tuberculosis strains,42.9%and 57.1% were identified to be Beijing family and non-Beijing family isolates respectively;these clinical strains of M.tuberculosis could be categorized into 5genogroups with VNTR,in which I genogroup（15.7%）consisted of 11 genotypes,II genogroup（35.7%）consisted of 25 genotypes,III genogroup（15.7%）consisted of 11 genotypes,IV genogroup（30.0%）consisted of 21 genotypes and V genogroup（2.9%）consisted of 2genotypes,there were no clustering strains.It is preliminarily confirmed the existence of high polymorphism of M.tuberculosis isolated from LuoDian County,II and IV genogroup are the main prevalent genogroup,and there is a certain proportion of nontuberculosis infection in the local area.