Army Tuberculosis Prevention and Control Key Laboratory, Institute for Tuberculosis Research, 309th Hospital of the Chinese PLA, Beijing, China.
Mol Diagn Ther. 2011 Dec 1;15(6):341-6. doi: 10.1007/BF03256469.
China is a country with a high prevalence of latent tuberculosis (TB) infection (LTBI) and has a policy of routine bacillus Calmette-Guérin (BCG) vaccination. The purified protein derivative (PPD) skin test cannot distinguish TB infection from BCG vaccination, and the diagnosis of LTBI lacks an accepted standard method. The primary objective of this study was to assess the potential of a highly sensitive whole-blood interferon (IFN)-γ release assay that uses recombinant culture filtrate protein (CFP)-10/early secretory antigenic target (ESAT)-6 fusion protein (rCFP-10/ESAT-6) as a stimulus for diagnosis of LTBI.
Between December 2009 and March 2010, a total of 892 new recruits to the army in Beijing, China, were interviewed and routinely examined by chest radiographs. IFNγ released from whole blood in response to stimulation with rCFP-10/ESAT-6 was detected with an enzyme-linked chemiluminescent immunoassay. The recruits were also intradermally injected with PPD to assess 72-hour skin induration (the PPD skin test).
Of the 892 participants, 450 (50.4%) had a positive PPD skin test and 244 (27.4%) had a positive whole-blood IFNγ release assay. Of 442 PPD-negative subjects, 88 (19.9%) had a positive whole-blood IFNγ test. Of 450 PPD-positive subjects, 156 (34.7%) had a positive whole-blood IFNγ test. Of 132 strongly PPD-positive subjects, 62 (47.0%) had a positive whole-blood IFNγ test. The agreement between the two tests was 57.2%. Of the 892 participants, 579 (64.9%) had clear vaccination scars on their arms, and of these, 382 (66.0%) had positive PPD skin responses and 162 (28.0%) were positive for the whole-blood IFNγ test.
The new whole-blood IFNγ release assay might be a better indicator of LTBI than the PPD test in China.
中国是潜伏性结核感染（LTBI）高发国家，且推行卡介苗（BCG）常规接种政策。结核菌素纯蛋白衍生物（PPD）皮肤试验无法区分结核感染与 BCG 接种，LTBI 的诊断缺乏公认的标准方法。本研究的主要目的是评估以重组培养滤液蛋白（CFP）-10/早期分泌抗原靶 6（ESAT-6）融合蛋白（rCFP-10/ESAT-6）为刺激物的高度敏感全血干扰素（IFN）-γ释放试验（IGRA）用于 LTBI 诊断的潜力。
2009 年 12 月至 2010 年 3 月，对北京 892 名新兵进行访谈和常规胸片检查。采用酶联化学发光免疫分析法检测 rCFP-10/ESAT-6 刺激后全血中 IFNγ 的释放情况。新兵还接受了皮内注射 PPD 以评估 72 小时皮肤硬结（PPD 皮肤试验）。
892 名参与者中，450 名（50.4%）PPD 皮肤试验阳性，244 名（27.4%）全血 IFNγ 释放试验阳性。442 名 PPD 阴性者中，88 名（19.9%）全血 IFNγ 试验阳性。450 名 PPD 阳性者中，156 名（34.7%）全血 IFNγ 试验阳性。132 名强阳性 PPD 者中，62 名（47.0%）全血 IFNγ 试验阳性。两种检测方法的一致性为 57.2%。892 名参与者中，579 名（64.9%）手臂上有明显的疫苗接种疤痕，其中 382 名（66.0%）PPD 皮肤反应阳性，162 名（28.0%）全血 IFNγ 试验阳性。
与 PPD 试验相比，新型全血 IFNγ 释放试验可能是中国 LTBI 的更好指标。
