Quantiferon Gold Test for Detecting TB Infection in HIV/AIDS Patients in Brazil

描述（由申请人提供）：结核病（TB）是艾滋病毒感染者最常见的死亡原因。在艾滋病毒感染者中诊断潜伏性结核感染（LTBI）具有挑战性，因为最常用的结核菌素皮肤试验（TST）已经过时，在艾滋病毒感染者和卡介苗接种人群中敏感性差，并且难以操作。世界卫生组织目前建议，在可以实施TST以检测LTBI的地区，建议仅对TST阳性的艾滋病毒感染者提供预防性治疗。一种新的血液检测方法，Quantiferon TB金管（QGIT）检测，最近已被美国FDA批准用于检测LTBI，然而，相对较少发表的研究评估了该方法在hiv感染患者中的应用，并且关于QGIT的常规使用的信息很少，即在常规临床护理条件下的测试性能和该血液测试的最佳操作。我们提出了一项聚类随机试验（CRT），比较QGIT在巴西里约热内卢公共HIV诊所就诊的HIV感染者与常规TST中的表现，并确定QGIT是否能更快地识别潜伏感染的HIV感染者，从而更快地启动结核病预防治疗。我们将QGIT检测与常规CD4监测相结合，消除临床常规工作人员的负担，尽量减少对常规抽血的干扰。在巴西里约热内卢，TST和异烟肼预防治疗的延误时间极长，等待TST的艾滋病毒感染患者患结核病的风险相当高，因此需要一种更好的战略。该研究的具体目的是：1)比较将QGIT与CD4采血相结合的影响，以及巴西巴西里约热内卢艾滋病诊所目前TST的标准护理流程对操作指标的影响；2)比较实施QGIT与TST标准实践的成本效益；3)探索影响QGIT成功实施的态度和操作因素。考虑到测试的参数，我们将QGIT与常规CD4抽血联系起来的主要重点是创新和合乎逻辑的。除了对干预措施的实施进行结构化的过程评估和确定QGIT与TST相比的成本效益之外，这些发现将提供迄今为止在发展中国家的操作环境中比较这两种检测的最佳证据，并指导在巴西和其他TST无法诊断艾滋病毒感染者潜伏感染的地区传播和实施这一战略。

DESCRIPTION (provided by applicant): Tuberculosis (TB) is the most common cause of death among people living with HIV. Diagnosing latent tuberculosis infection (LTBI) among HIV-infected patients is challenging, as the most commonly used test, the tuberculin skin test (TST), is out-dated, has poor sensitivity in HIV-infected and BCG vaccinated populations, and is operationally difficult to administer. The World Health Organization currently recommends that in regions where the TST can be implemented to detect LTBI, provision of preventive therapy is recommended only for HIV-infected patients with a positive TST. A new blood assay, Quantiferon TB Gold In-Tube (QGIT) test, has been recently approved by the US FDA for detecting LTBI, however relatively few published studies have evaluated this assay in HIV-infected patients and little information exists about the routine use of QGIT, i.e. test performance under routine clinical care conditions and optimal operationalization of this blood test. We propose a cluster randomized trial (CRT) to compare QGIT performance in HIV-infected persons attending public HIV clinics in Rio de Janeiro, Brazil with routine TST, and to determine if QGIT more quickly identifies HIV-infected patients who are latently infected and leads to faster initiation of TB preventive therapy. We will link QGIT testing with routine CD4 monitoring which will eliminate the burden of the routine clinic staff and minimally interfere with routine blood draws. Delays in TST and provision of isoniazid preventive therapy in Rio de Janeiro are extremely long, and risk of TB disease is quite high among HIV-infected patients waiting for a TST, thus a better strategy is needed. The specific aims of the study are 1) to compare the impact of linking QGIT with CD4 blood collection and the current standard of care process of TST in HIV clinics in Rio de Janeiro, Brazil on operational metrics, 2) to compare cost-effectiveness of implementing QGIT versus standard practice of TST, and 3) to explore attitudinal and operational factors influencing successful implementation of QGIT. Our primary focus on linking QGIT with routine CD4 blood draws is innovative and logical given the parameters of the test. These findings, in addition to conducting a structured process evaluation of the implementation of the intervention and determining the cost effectiveness of QGIT compared to TST will provide the best evidence to date comparing these two tests in an operational setting in a developing country, and guide dissemination and implementation of this strategy throughout Brazil and other regions where TST is ineffective at diagnosing latent infection in HIV- infected patients.