北京结核菌株分子流行病学的研究

目的　北京结核分支杆菌分子流行病学的研究。方法 (1)使用标准化的RFLP法检测并分析从128位初治患者分离的结核分支杆菌IS6110指纹多态性;(2)对选例患者进行社会人口学和流行病学调查问卷;(3)分析结核分支杆菌IS6110指纹多态性特征与流行病学的关系。结果 (1)根据IS6110指纹特征的同源性,检测的128株结核分支杆菌可基本分为3组,A、B组的菌株间因具有较高的同源性而被称为“北京基因型”菌株,并且此类菌株在检测菌株中所占的比例较高(103/128,80.5%);C组菌株间同源性较低,多态性变化多而被称为“非北京基因型”,仅占19.5%。(2)从较低年龄(<40岁)患者分离菌株的多态性变化,与从较高年龄(>40岁)患者分离菌株多态性变化比较存在差异,提示“北京基因型”菌株不是由于BCG接种而造成的选择性优势。(3)检测菌株的多态性变化与患者结核病接触史、患者长期居住地、菌株药物敏感性情况无明显联系。结论 结核分支杆菌的指纹分析对结核病现代流行病学的研究是一个有用的工具。

The molecular epidemiologyof Mycobacterium tuberculosis in Beijing

Objective　Typing of Mycobacterium tuberculosis strains and epidemiological studies in Beijing.Methods　(1)To detect and analyze the restriction fragment length polymorphism (RFLP) of M.tuberculosis isolated from 128 new patients with pulmonary tuberculosis by using standardized method.(2)A sociodemographical and epidemiological questionnaire investigated all patients selected in this study.(3)The relationship of genotype of M.tuberculosis and their epidemiology were analyzed.Results　(1)128　M.tuberculosis detected were belonged in 3 groups, according to their homology of IS6110 fingerprinting.The strains in A and B groups were called as “Beijing genotype strains" because these strains had high homology, and they had a high percentage (103/128,80.5%) in all strains detected.Strains in group C, called as “non-Beijing genotype strains",had lower homology and only 19.5% in all strains detected.(2)The polymorphism of the strains isolated from the younger patients (＜40) were different significantly compared with the strains isolated from those elder patients (＞40).The selectivity predominance of “Beijing genotype" was not due to BCG vaccine widely.(3)The polymorphism of the strains detected were not correlated significantly to past TB contracted history of the patients investigated,living in urban or rural area of Beijing and the drug-resistance of the strains.Conclusion　Fingerprinting analysis of M.tuberculosis can be a useful tool for the study of modern epidemiology of tuberculosis.