Kakkar F, Allen Ud, Ling D, Pai M, Kitai Ic
Paediatr Child Health. 2010 Oct;15(8):529-38. doi: 10.1093/pch/15.8.529.
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.
γ-干扰素释放试验的开发是为了克服结核菌素皮肤试验（TST）在诊断潜伏性结核感染（LTBI）时存在的缺陷和后勤困难。这些血液检测通过致敏淋巴细胞对结核分枝杆菌特异性抗原的反应来测量体外γ-干扰素的产生。加拿大有两种γ-干扰素释放试验已注册使用：全血γ-干扰素释放试验（澳大利亚Cellestis公司）和T.SPOT-TB检测（英国牛津免疫技术公司）。由于缺乏LTBI的金标准以及关于其使用的儿科数据有限，这些检测的评估受到了阻碍。似乎它们比TST更具特异性，可能有助于评估真正LTBI低风险的TST阳性患者。此外，在免疫功能低下的患者、非常年幼的儿童以及传染性成人的密切接触者中，如果与TST联合使用，它们可能会增加检测的敏感性。本文描述了这些检测、它们的局限性及其在儿科临床实践中的应用。
