TB Diagnostics at the Point of Care

描述（由申请人提供）：在所有疾病中，结核病（TB）是白人和少数民族之间健康差距最大的疾病之一。在美国，每有一个白人感染结核病，估计就有9个非洲裔美国人、8个拉丁裔美国人、6个印第安人、23个亚洲人和21个夏威夷原住民/太平洋岛民感染这种疾病。与这种差异更为复杂的是结核病耐药突变的流行，这些突变具有相关的1000个多态性，涉及36个基因、两个启动子区域和一个核糖体RNA编码区[3]。目前的方法主要适用于富裕的医疗保健社区，利用微生物培养，这需要复杂的实验室和数周才能确定结果。社会经济地位较低的少数民族在通勤和/或随访医生方面遇到困难，可能导致缺乏适当的治疗。一种检测结核病及其对一线药物（异烟肼、利福平、乙胺丁醇和吡嗪酰胺）耐药性的低成本、简单和快速的即时检测方法将改善这些少数民族社区的结核病诊断。然而，目前的技术缺乏灵敏度、特异性和/或多路复用能力来实现这一目标。因此，我们建议开发一种POC设备，提供培养方法的敏感性，核酸方法的特异性和广泛的突变覆盖范围。为了实现这一目标，我们将推进我们的TruArray平台（半球形多孔凝胶滴微阵列），用于使用片上PCR和我们现有的耐多药结核病PCR微阵列生物芯片进行结核病诊断。在第一阶段，我们展示了样品制备方法、pcr微阵列生物芯片和原型POC仪器的可行性。对于第二阶段，我们建议扩大我们测试的覆盖范围，包括对所有一线药物产生耐药性的其他突变，将该测试整合到我们的POC仪器上，并将该系统推广到墨西哥华雷斯的特别医学实验室。

DESCRIPTION (provided by applicant): Of all diseases, tuberculosis (TB) represents one of, if not, the greatest health disparity between whites and minorities [1]. For every TB-infected white person in the United States, there are an estimated 9 African- Americans, 8 Latinos, 6 Native Americans, 23 Asians, and 21 Native Hawaiian/Pacific Islanders with this disease [2]. Compounded with this disparity is the prevalence of drug-resistant mutations of TB, which have an associated 1000 polymorphisms that span 36 genes, two promoter regions, and one ribosomal RNA coding region [3]. Current methodologies, available primarily to affluent healthcare communities, utilize microbial cultures, which require sophisticated laboratories and weeks before a result can be determined. Difficulties for minorities in a low socioeconomic class to commute and/or follow up with their physicians can result in a lack of appropriate treatment. A low-cost, simple, and rapid point-of-care (POC) test that detects TB and its resistance to first-line drugs (isoniazid, rifampin, ethambutol,and pyrazinamide) would improve TB diagnostics for these minority communities. However, current technologies lack sensitivity, specificity, and/or multiplexing capacity to achieve this goal. We, therefore, propose to develop a POC device that offers the sensitivity of culture methods, specificity of nucleic acid methods, and a broad coverage of mutations. To accomplish this, we will advance our TruArray platform (hemispherical porous gel drop microarrays) for TB diagnostics using on-chip PCR and our existing MDR-TB PCR-microarray biochips. During Phase 1 we demonstrated feasibility of our sample preparation approach, our PCR-micorarray biochips, and prototype POC instrument. For Phase 2 we propose to expand the coverage of our test to include additional mutations that confer resistance to all first-line drugs, integrate this test onto our POC instrument, and translae this system to Laboratorios Medicos Especializados in Juarez, Mexico.