上海市结核感染T淋巴细胞斑点试验阳性的结核病密切接触者结核病发病的前瞻性观察性研究

Risk of developing tuberculosis in T-cell spot test of tuberculosis infection positive close contacts of tuberculosis patients in Shanghai:a prospective observational study

目的了解上海市结核病密切接触者中结核潜伏感染(latent tuberculosis infection,LTBI)者的结核病发病风险及其时间特征。方法采用前瞻性观察性研究方法,以2009至2010年上海市7个区户籍人口中确诊肺结核患者的密切接触者为研究对象,采用结核感染T淋巴细胞斑点试验(T-cell spot test of tuberculosis infection,T-SPOT.TB)判断结核分枝杆菌感染情况以识别LTBI,同时采用问卷调查的方法收集研究对象的基本信息和结核病密切接触史。通过结核病登记报告系统识别LTBI者在检测后连续9年内的发病情况,计算其结核病发病率和发病密度。采用χ^(2)检验对不同性别和年龄分组的发病率进行分层分析。结果2009年至2010年,共纳入376例确诊肺结核患者的982名密切接触者,其中287名密切接触者经T-SPOT.TB检测为LTBI。接受基线调查时感染者中位年龄为54岁,36.6%(105/287)的LTBI者为男性。截至2019年12月287名LTBI者中共发现5例新发结核病患者,2年累积发病率为0.35%,5年累积发病率为1.05%,9年累积发病率为1.74%(95%可信区间0.57%~4.02%),中位发病时间为3.67年;研究期间共观察了2666.75人年,结核病发病密度为1.875/1000人年。不同年龄(χ^(2)=0.600,P>0.05)和性别(χ^(2)<0.001,P>0.05)的LTBI者的结核病9年累积发病率差异均无统计意义。结论结核病患者密切接触者中的LTBI者的结核病发病集中在接触后前5年左右。

Objective To investigate the risk and temporal characteristics of tuberculosis(TB)in persons with latent tuberculosis infection(LTBI)among close contacts of TB patients in Shanghai.Methods This was a prospective observational study,the study subjects were the close contacts of TB patients who tested positive for Mycobacterium tuberculosis infection by T-cell spot test of tuberculosis infection(T-SPOT.TB)among the registered population in seven districts of Shanghai from 2009 to 2010.Questionnaire interview was applied to investigate the basic information and contact history.The LTBI cases during nine consecutive years were identified through the TB registration and reporting system.Cumulative incidence rate and incidence density of TB in tuberculosis-infected close contacts were estimated.Chi-square test was used to compare the incidence rate among different sex and age groups.Results In total,376 pulmonary TB patients and their 982 close contacts were enrolled in the baseline survey from 2009 to 2010.Of them,287 close contacts were tested positive for Mycobacterium tuberculosis infection by T-SPOT.TB.The median age of persons with LTBI at the time of survey was 54 years old,and 36.6%(105/287)were male.By the end of December 2019,five new TB cases were detected among the 287 close contacts with LTBI.The two-year and five-year cumulative incidence were 0.35%and 1.05%,respectively.The nine-year cumulative incidence was 1.74%(95%confidence interval 0.57%-4.02%).The median duration for TB occurrence was 3.67 years.The incidence density of TB was 1.875/1000 person-years with a total of 2666.75 observation person-years.There were no significant differences in the nine-year cumulative incidence of TB among close contacts with LTBI by age and sex(χ^(2)=0.600,<0.001,respectively,both P>0.05).Conclusion The occurrence of TB among close contacts with LTBI is concentrated in the first five years after TB contact.