结核感染T淋巴细胞斑点试验检测艾滋病合并结核病患者的敏感度及影响因素

Diagnostic sensitivity and related impact factors of T cell spot test of tuberculosis in acquired immunodeficiency syndrome/tuberculosis patients

目的探讨结核感染T淋巴细胞斑点试验（T—SPOT．TB）检测艾滋病合并结核病患者的敏感度及影响因素。方法T—SPOT．TB检测艾滋病合并结核病患者92例，分析CD4＋T淋巴细胞计数对T-SPOT．TB敏感度的影响。Logistic多因素分析T—SPOT．TB敏感度的影响因素。选择2015年1月至2016年1月晚期艾滋病合并结核病患者19例，分别以Ficoll分层液法提取PBMC和Percoll分层液法提取淋巴细胞后进行T—SPOT．TB，采用McNemar检验比较其优劣性。结果92例艾滋病合并结核病患者中，T—SPOT．TB阳性51例，敏感率为55．4％。CD4＋T淋巴细胞〈20／μL时T—SPOT．TB的敏感度为26．3％（10／38），CD4＋T淋巴细胞〉200／μL时敏感度为92．9％（13／14）。Logistic多因素分析显示，艾滋病合并结核病患者中，合并肺外结核患者的T—SPOT．TB敏感度高于单纯肺结核患者（OR=3．042，P=0．038）；CD4＋T淋巴细胞计数与T—SPOT．TB敏感度呈正相关，每升高100／μL其敏感度增加2．889倍（OR=3．889，P=0．016）；淋巴细胞占PBMC比例与T—SPOT．TB敏感度呈正相关，每提高30％其敏感度增加1．393倍（OR=2．393，P=0．045）。Percoll分层液法提取淋巴细胞后进行T—SPOT．TB的敏感度为52．6％（10／19），Ficoll分层液法提取PBMC后进行TSPOT．TB的敏感度为36．8％（7／19），差异无统计学意义（P=0．375）。结论基于淋巴细胞的T—SPOT．TB的敏感度高于基于PBMC的T—SPOT．TB。

Objective To analyze the diagnostic sensitivity and related impact factors of T cell spot test of tuberculosis （T-SPOT. TB） test in acquired immunodeficiency syndrome （AIDS）/tuberculosis （TB） patients. Methods Ninety-two confirmed cases with AIDS/TB coinfection were tested by T-SPOT. TB, and the impact of CD4＋ T cells counts on the diagnostic sensitivity was analyzed. Multivariate Logistic analysis was used for the analysis of impact factors of T-SPOT. TB sensitivity. Blood samples of 19 cases with advanced stage AIDS/TB from January 2015 to January 2016 were collected, and peripheral blood mononuclear cell （PBMC） were isolated by Ficoll method, and lymphocytes were isolated by Percoll method. McNemar test was used for the comparison of these two methods. Results Among the 92 patients with AIDS/TB, T-SPOT. TB tests were positive in 51 cases, with positive rate of 55.4%. The sensitivity was 26.3% （10/38） when CD4＋ T cell count less than 20/μL, and that was 92.9% （13/14） when CD4＋T cell more than 200/μL. In Logistic analysis, the sensitivity of T-SPOT. TB test in patients with extra-pulmonary tuberculosis was better than that in pulmonary tuberculosis patients （OR= 3. 042, P=0. 038）. The sensitivity of T-SPOT. TB was positively correlated with CD4＋ T cell count, and the sensitivity increased by 2. 889 times when CD4＋T cells increasing 100/μL （OR=3. 889, P=0. 016）. The percentage of lymphocytes in PBMC was also positively correlated with T-SPOT. TB positivity, and the sensitivity increased by 1. 393 times when the percentage increasing 30% （OR=2. 393, P〈0. 045）. When Percoll was used for lymphocytes isolation, the T-SPOT. TB sensitivity was 52.6 % （10/19）, and when Ficoll was used for PBMC isolation, the sensitivity was 36.8% （7/19）. The difference was not statistically significant （P=0. 375）. Conclusion The sensitivity of T-SPOT. TB test based on lymphocytes is higher than that based on PBMC.