Culture-free identification of pathogens common in endocarditis directly from patient specimens

项目摘要 感染性心内膜炎（IE）是一种危及生命的疾病，每年影响大约45，000名美国人。IE是 其特征在于内表面上的微生物赘生物，其引起严重的心脏损伤， 持续性血流感染（BSI）导致败血症。不治疗IE是致命的。在标准中， 为了建立IE并最有效地治疗患者，血培养对于确定病原体是必不可少的。 然而，培养物显示出两个主要的缺点，这会延迟适当的抗菌剂的施用： (1)周转时间长，需数天甚至数周;（2）由于以下原因之一，假阴性结果的发生率高 抗生素预处理或存在难以培养的病原体。因为时间对于最佳的 结果与最小的并发症，治疗往往是在诊断前开始与广泛的鸡尾酒， 广谱（即非靶向）抗菌药物，导致大多数患者治疗不当， 而不是不必要地治疗疾病。因此，至关重要的是要推进创新的诊断方法， 其不依赖于培养，以便快速过渡到个性化的抗微生物干预。 为了解决这一未满足的需求，HelixBind将开发第一个能够识别 在2.5小时内诱发IE的病原体。HelixBind的方法利用了多个新颖的创新， 样本到答案。此外，由于检测不需要培养，我们的方法特别适合于 检测挑剔的病原体，今天的诊断标准经常无法检测到。我们提出的 感染性心内膜炎病原体鉴定试验，称为IE/PID，预计将具有深远的临床意义。 通过使医生能够在几个小时内应用个性化和证据驱动的干预措施， 而不是几天;最终改善结果和抗菌管理。此前，HelixBind 展示了一个核心病原体识别（C/PID）平台，针对“一般”高危患者人群 用于血流感染引起的败血症。C/PID检测21种最常见的导致BSI的病原体 在一个单一的测试直接从血液，需要不到2.5小时，从样品到答案，并显示单一 整个样本组的CFU/ml LOD。C/PID在使用临床标本的盲法初步研究中得到验证 并且显示出>95%的灵敏度和>89%的特异性。IE/PID将采用与C/PID类似的流程， 检测与IE相关的最常见病原体，包括难养和不可培养的病原体。 我们的具体目标和可量化的交付成果旨在证明在时间内的可行性， 第一阶段的资本限制。为了取得成功，我们组建了一个检测开发专家团队， 人工核酸，由领先的临床微生物学家提供指导。实现了我们的具体 在第二阶段，我们将开发可部署的仪器/消耗品，扩大测试面板， 通常被认为是“不可培养的”病原体，如贝氏柯克斯体和巴尔通体属，以及核查和 在设盲研究中使用临床标本验证自动诊断平台。

PROJECT SUMMARY Infective Endocarditis (IE) is a life-threatening disease that affects roughly 45,000 Americans annually. IE is characterized by microbial vegetations on the endocardial surface which induce serious heart damage and persistent bloodstream infections (BSIs) leading to sepsis. Left untreated IE is fatal. Among the criteria to establish IE and treat patients most effectively, blood cultures are indispensable to identify the etiologic agent. Cultures, however, display two major weaknesses which delay the administration of the proper antimicrobials: (1) High turnaround time of days or even weeks and (2) high prevalence of false-negative results due to either pre-treatment with antibiotics or the presence of difficult to culture pathogens. As time is of essence for optimal outcomes with minimal complications, treatment is often initiated prior to diagnosis with a cocktail of broad spectrum (i.e. not targeted) antimicrobials, leaving the majority of patients treated inappropriately and those without the disease treated unnecessarily. It is therefore critical to advance innovative diagnostic approaches, which do not rely on culturing, in order to rapidly transition to personalized antimicrobial interventions. To address this unmet need, HelixBind will develop the first culture-free diagnostic assay capable of identifying pathogens which induce IE in under 2.5 hours. HelixBind’s approach leverages multiple novel innovations from sample-to-answer. Further, as detection does not require cultures, our approach is particularly suited to the detection of fastidious pathogens, which today’s diagnostic standard frequently fail to detect. Our proposed Infective Endocarditis Pathogen Identification assay, termed IE/PID, is expected to have a profound clinical impact by enabling the physician to apply a personalized and evidence-driven intervention within a few hours, rather than days; ultimately improving both outcomes and antimicrobial stewardship. Previously, HelixBind demonstrated a Core Pathogen Identification (C/PID) platform, aimed at the ‘general’ patient population at-risk for sepsis caused by bloodstream infections (BSIs). C/PID detects 21 of the most prevalent BSI-causing pathogens in a single test directly from blood, requires less than 2.5 hours from sample-to-answer, and displayed single CFU/ml LODs across the entire panel. C/PID was validated in a blinded pilot study utilizing clinical specimens and demonstrated >95% sensitivity and >89% specificity. IE/PID will utilize similar processes as C/PID and will detect the most prevalent pathogens associated with IE including fastidious and uncultureable pathogens. Our Specific Aims with quantifiable deliverables are designed to demonstrate feasibility within the time and capital constraints of a Phase I. To succeed, we have assembled a team of experts in assay development and artificial nucleic acids, supported by leading clinical microbiologists for guidance. Having achieved our Specific Aims, we will, in Phase II, develop deployable instrumentation/consumables, expand the test panel to include pathogens generally deemed as ‘unculturable’, such as Coxiella burnetii and Bartonella spp., and verify and validate an automated diagnostic platform with clinical specimens in a blinded study.