Bloodstream infection detection directly on whole blood

直接在全血中检测血流感染 摘要 败血症是一种危及生命的疾病，由血液中真菌或细菌的存在引发，从而影响 美国每年有130万人1.快速使用抗菌药是脓毒症的关键 治疗2-4然而，目前诊断血液感染的金标准是血培养(BC)，它 需要一到五天的时间。5为了向医生提供正确治疗所需的诊断信息 对于患者，我们建议开发一个自动化平台，用于快速、广泛和具有成本效益的识别 不含BC的全血中的微生物。在这项建议中，我们将重点发展 仪器和第一个将直接检测全血真菌的化验。 新的平台将基于单分子扫描(SMS)，一种新的样品制备和分子 Scanogen公司开发了检测方法。真菌化验(SMS-Fungi)将检测和鉴定最多的五种 引起血液感染的常见念珠菌以及隐球菌属。化验结果会 也利用以广泛保守的序列为目标的探针来检测整个 血样。我们的目标是开发一种1小时、准确、广泛、多路、全自动化和低成本的 测试，这将有助于医生立即开始适当的抗真菌治疗。 在第一阶段，我们开发了一种能够直接检测全血中真菌的检测方法。我们都测试过了 与血液感染中常见的四种真菌的特定和广泛的探针。我们发现 该检测具有高度的特异性和高度的敏感性，可用于临床病例的诊断。 检测下限(LOD)低至1cfu/ml。在本项目中，我们将完成该方法的开发 协议通过加入新的探针和优化整体分析(目标1)，开发一个测试版原型系统 包括一台自动化仪器和一次性墨盒(目标2)，并在试行阶段对新系统进行评估 分析和临床验证研究(目标3)。我们将利用在开发 Scanogen公司目前正在开发一种快速检测结核病的护理点检测方法，并正在进行工作 拥有一个多学科团队，其中包括分析开发和仪器开发方面的专家，包括 贝顿·迪金森公司前工程副总裁，真菌感染诊断和治疗专家 来自约翰·霍普金斯大学的工程师和Key Technologies的工程师。 我们的目标是开发和验证一个用于快速分析微生物的自动化分子平台 并开发了其首个真菌检测方法。如果成功，新的化验方法将显著改进。 通过减少诊断延迟和及时启动适当的治疗来管理真菌血症患者 抗真菌治疗。

Bloodstream infection detection directly on whole blood Summary Sepsis is a life-threatening condition triggered by the presence of fungi or bacteria in the bloodstream that affects 1.3 million people each year in the United States.1 Rapid antimicrobial administration is critical for sepsis treatment.2-4 However, the current gold standard for bloodstream infection diagnosis is blood culture (BC), which takes one to five days.5 In order to provide physicians with the needed diagnostic information to properly treat patients, we propose the development of an automated platform for rapid, broad and cost-effective identification of microorganisms in whole-blood without BC. In this proposal, we will focus on the development of the instrument and the first assay which will detect fungi directly on whole-blood. The new platform will be based on Single Molecule Scanning (SMS), a novel sample preparation and molecular detection method developed at Scanogen. The fungi assay (SMS-Fungi) will detect and identify the five most common Candida species that cause bloodstream infections as well as the Cryptococcus genus. The assay will also utilize probes that target broadly conserved sequences to detect the presence of any fungi in the whole- blood specimen. The goal is to develop a 1-hour, accurate, broad, multiplexed, fully-automated and cost-effective assay, that will aid physicians to start proper antifungal therapy without delay. In phase I, we developed an assay protocol capable of detecting fungi directly in whole-blood. We tested both specific and broad-range probes with four species of fungi commonly found in bloodstream infections. We found that the assay is highly specific and has the high sensitivity required for the diagnosis of clinical cases with a limit of detection (LOD) as low as 1 CFU/ml. In this project, we will complete the development of the assay protocol by including new probes and optimizing the overall assay (Aim 1), develop a beta-prototype system consisting of an automated instrument and disposable cartridge (Aim 2) and evaluate the new system in pilot analytical and clinical validation studies (Aim 3). We will leverage the experience attained in the development of a rapid assay for point of care detection of Tuberculosis currently under development at Scanogen, and work with a multidisciplinary team that includes experts in assay development and instrument development including the former Vice President of Engineering at Becton Dickinson, experts in fungal infection diagnosis and treatment from Johns Hopkins University and engineers from Key Technologies. Our goal is to develop and validate an automated molecular platform for rapid analysis of microorganisms in whole-blood and develop its first assay for fungi detection. If successful, the new assay will dramatically improve the management of patients with fungemia by reducing diagnostic delay and enabling timely initiation of proper antifungal treatment.