结核感染T淋巴细胞斑点试验技术在学校结核密切接触者中筛查潜伏结核感染的应用

Application of T-SPOT. TB in tuberculosis contact investigation for screening latent tuberculosis infection at college

目的了解学校潜伏结核感染（LTBI）率，评价结核感染T淋巴细胞斑点试验（T—SPOT．TB）筛查LTBI的特异性和可行性。方法某高校出现1例痰结核杆菌阳性学生后，对同年级的803名学生进行结核病接触者筛查和问卷调查，筛查内容包括胸透、结核菌素皮肤试验（TST）、T-SPOT．TB试验。结果803名学生中，研强阳性率22．3％（179／803），T—SPOT．TB阳性率9．1％（73／803），2种测定方法的符合率74．6％（599／803，95％可信区间：71．5％～77．6％）。佟T在接种过卡介苗的学生组中较未接种过卡介苗的学生组中更容易出现阳性（r=12．54，P=0．00），T-SPOT．TB结果不受卡介苗接种的影响（χ^2=1．16，P=0．28）。结论佟T和T—SPOT.TB结果一致性低（Kappa=0．07，P〈0．01），但T-SPOT．TB结果不受BCG接种的影响，特异性优于TST。

Objective To investigate the rate of latent tuberculosis infection （LTBI） and evaluate the specificity and feasibility of T-SPOT. TB in suspicious tuberculosis （TB） outbreak incidence at a college. Methods When a sputum smear positive student emerged at the college in 2006,803 students in the same grade of the index case were screened for Mycobacterium tuberculosis infection with chest X-ray examination, tuberculin skin test （TST）, T-SPOT. TB and questionnaire investigation. Results The rate of strong positive of TST and T-SPOT. TB were 22.3% （ 179/803 ）, and 9. 1% （ 73/803 ）, respectively. The concordance rate between TST and T-SPOT. TB was 74. 6% （95% CI： 71.5%-77. 6% ） . TST was significantly more likely to be positive in BCG-vaccinated students than that in non-vaccinated ones （X2 = 12.54, P =0. 00）, whereas T-SPOT. TB results were not associated with BCG vaccination （χ^2 = 1.16, P = 0. 28）. Conclusions With T-SPOT. TB positive results as the standard for diagnosis of latent TB, the rate of LTB[ in the college was 9. 1%. During the latent TB screening, agreement between tests was low （Kappa = 0.07, P 〈 0.01 ） , but T-SPOT. TB is not affected by BCG vaccination, indicated its better specificity for screening latent TB than that of TST.