结核分枝杆菌北京基因型菌株与重庆地区结核患儿耐药表型的相关分析

Correlation between Beijing genotype strains of Mycobacterium tuberculosis and drug-resistant phenotypes in Chongqing children with tuberculosis

目的研究结核分枝杆菌北京基因型菌株与结核患儿耐药表型及其相关因素。方法采用定向缺失多重酶链聚合反应技术(deletion-targeted multiplex PCR,DTM-PCR)对从143例患儿分离得到的结核分枝杆菌进行北京基因型菌株鉴定,并使用绝对浓度法进行药敏实验。收集患者的性别、年龄、居住地、卡介苗接种史和结核性脑膜炎病史等相关因素资料。采用χ2检验和Fisher确切概率法分析北京基因型与相关因素以及耐药表型之间的关系。结果在143株结核分枝杆菌中,91株为北京基因型,占63.6%,北京基因型菌株与年龄、性别、居住地、卡介苗接种和结核性脑膜炎无关(P>0.05)。北京基因型菌株在耐链霉素菌株(16.5%,15/91)和耐异烟肼菌株(15.4%,14/91)中的比例显著高于非北京基因型(3.8%,2/52;3.8%,2/52)(P<0.05)。结论北京基因型菌株是重庆地区儿童结核患者中流行的优势菌群,患儿的年龄、性别、居住地、是否接种卡介苗和是否为结核性脑膜炎与北京基因型菌株无关,感染北京基因型菌株的结核患儿更易出现链霉素和异烟肼耐药。

Objective To study the correlation between Beijing genotype strains of Mycobacterium tuberculosis and drug resistance phenotypes in children with tuberculosis. Methods Beijing genotype strains of Mycobacterium tuberculosis were detected in 143 children with tuberculosis by deletion-target multiple PCR （DTM-PCR）. Drug susceptibility testing was performed using the absolute concentration method. Data about the children with tuberculosis were collected, including their age, sex, residence, BCG vaccination and tuberculous meningitis. Correlation between Beijing genotype strains of Mycobacterium tuberculosis, drug-resistance phenotypes and related factors were analyzed by Chi-square test and Fisher’s exact test, respectively. Results Of the 143 clinical isolates of Mycobacterium tuberculosis,91 （63.6%） were Beijing genotype strains. Beijing genotype strains were not correlated with the age, sex, residence, BCG vaccination and tuberculous meningitis（P0.05）. The percentage of isoniazid-resistant isolates （15.4%,14/91） and streptomycin-resistant isolates（16.5%,15/91） was significantly higher in Beijing genotype strains than in non-Beijing genotype strains（3.8%,2/52;3.8%,2/52,P0.05）. Conclusion The Beijing genotype strains of Mycobacterium tuberculosis are predominant in children with tuberculosis in Chongqing and are not correlated with their age, sex, residence, BCG vaccination and tuberculous meningitis. Isoniazid-resistance and streptomycin-resistance are easier to occur in children infected with Beijing genotype strains.