Sharma Surendra K, Vashishtha Richa, Chauhan L S, Sreenivas V, Seth Divya
Department of Internal Medicine, All India Institute of Medical Sciences, New Delhi, India.
National Center for Disease Control (NCDC)2, New Delhi, India.
PLoS One. 2017 Jan 6;12(1):e0169539. doi: 10.1371/journal.pone.0169539. eCollection 2017.
There are currently two tests for diagnosing latent tuberculosis infection (LTBI); TST and IGRA. However, it is still unclear that which one of these tests performs better in high TB-burden settings.
1511 household contacts of pulmonary TB patients were enrolled to compare the performance of TST and IGRA for LTBI. At baseline all participant underwent testing for IGRA [QuantiFERON-TB® Gold In-tube (QFT-GIT) assay] and TST [2 tuberculin unit (TU), purified protein derivative (PPD), RT23, Staten Serum Institute (SSI), Copenhagen, Denmark]. All the household contacts were followed-up for two years for incident TB cases.
Active TB was diagnosed in 76 household contacts at an incidence rate of 2.14 per 1000 person-years. Both, TST [Hazard Ratio (HR): 1.14, 95% confidence interval (CI): 0.72-1.79, p = 0.57], as well as QFT-GIT assay (HR: 1.66, 95% CI: 0.97-2.84, p = 0.06) results at baseline were not significantly associated with subsequent development of active TB among household contacts of pulmonary TB patients.
Neither TST nor IGRA predicted subsequent development of active TB among household contacts of pulmonary TB patients during follow-up. However, keeping in view the cost, and other logistics, TST remains the most preferred method for LTBI diagnosis in resource-limited, high TB-burden settings.
目前有两种用于诊断潜伏性结核感染（LTBI）的检测方法；结核菌素皮肤试验（TST）和干扰素-γ释放试验（IGRA）。然而，在高结核病负担环境中，尚不清楚这两种检测方法中哪一种表现更佳。
招募了1511名肺结核患者的家庭接触者，以比较TST和IGRA检测LTBI的性能。在基线时，所有参与者均接受了IGRA检测[全血γ-干扰素释放试验（QFT-GIT）]和TST检测[2结核菌素单位（TU），纯蛋白衍生物（PPD），RT23，丹麦哥本哈根国家血清研究所（SSI）]。对所有家庭接触者进行了为期两年的随访，以观察结核病发病情况。
76名家庭接触者被诊断为活动性结核病，发病率为每1000人年2.14例。基线时，TST[风险比（HR）：1.14，95%置信区间（CI）：0.72-1.79，p=0.57]以及QFT-GIT检测结果（HR：1.66，95%CI：0.97-2.84，p=0.06）与肺结核患者家庭接触者随后发生活动性结核病均无显著关联。
在随访期间，TST和IGRA均未预测肺结核患者家庭接触者随后发生活动性结核病。然而，考虑到成本和其他后勤因素，在资源有限、高结核病负担的环境中，TST仍然是LTBI诊断的最优选方法。
