The interferon-gamma-release assays were developed to overcome the pitfalls and logistic difficulties of the tuberculin skin test (TST) for the diagnosis of latent tuberculosis infection (LTBI). These blood tests measure the in vitro production of interferon-gamma by sensitized lymphocytes in response to Mycobacterium tuberculosis-specific antigens. Two interferon-gamma-release assays are registered for use in Canada: the QuantiFERON-TB Gold In-Tube assay (Cellestis Inc, Australia) and the T.SPOT–TB test (Oxford Immunotec, United Kingdom). Evaluation of these tests has been hampered by the lack of a gold standard for LTBI, and limited paediatric data on their use. It appears that they are more specific than the TST, and may be useful for evaluating TST-positive patients at low risk of true LTBI. Moreover, they may add sensitivity if used in addition to the TST in immunocompromised patients, very young children and close contacts of infectious adults. A summary of these tests, their limitations and their application to clinical paediatric practice are described.

中文翻译：

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儿童结核病：新的诊断血液测试。


开发干扰素-γ释放测定法是为了克服结核菌素皮试（TST）诊断潜伏性结核感染（LTBI）的缺陷和后勤困难。这些血液测试测量了敏化淋巴细胞响应结核分枝杆菌特异性抗原而产生的干扰素-γ的体外情况。两种干扰素 γ 释放检测在加拿大注册使用：QuantiFERON-TB Gold In-Tube 检测（Cellestis Inc，澳大利亚）和 T.SPOT–TB 检测（Oxford Immunotec，英国）。由于缺乏 LTBI 的黄金标准以及有关其使用的儿科数据有限，这些测试的评估受到阻碍。它们似乎比 TST 更具特异性，可能有助于评估真正 LTBI 风险较低的 TST 阳性患者。此外，如果在免疫功能低下的患者、幼儿和感染性成人的密切接触者中除 TST 之外使用，它们可能会增加敏感性。描述了这些测试的总结、其局限性及其在儿科临床实践中的应用。