Bloodstream infection detection directly on whole blood

 描述（由申请人提供）：脓毒症是对感染的全身炎症反应，在美国每年影响约100万人，并导致高达50%的严重受影响患者死亡。快速和适当的抗菌药物管理是脓毒症的关键。治疗每延迟一小时，感染性休克患者的生存率就会下降8%。血培养是金标准诊断方法，然而，它需要一天以上的时间才能提供结果。因此，患者接受广谱抗生素或在最初几小时内可能不接受治疗。分子检测是一种有吸引力的解决方案，然而，目前可用的测试是基于细菌基因组DNA的PCR扩增，然后是复杂的检测策略。这些技术受到DNA污染的影响，缺乏足够的灵敏度并且昂贵。在这里，我们建议开发一种新的平台，用于快速和廉价的全血中的微生物鉴定，而无需血液培养。新平台将基于单分子扫描（SM-扫描），这是一种新的分子检测方法，其中无需PCR扩增即可检测探针与靶核酸的杂交（专利申请中）。SM-扫描使用直接和廉价的检测策略。初步结果表明，SM扫描可以检测5大肠杆菌细胞。在本提案中，我们将通过开发一种能够在不到1.5小时的时间内以极高的灵敏度检测血液样本中微生物的检测方法来证明SM扫描的特性。目标1：开发一种快速检测方法，能够以高灵敏度检测5 ml全血样本中是否存在细菌。目的2着重于开发和确定能够在单一测定中检测细菌和真菌的多重测定的性能。

 DESCRIPTION (provided by applicant): Sepsis is a whole-body inflammatory response to infection that affects approximately 1 million people each year in the United States and kills up to 50 percent of severely affected patients. Rapid and appropriate antimicrobial administration is critical for the management of sepsis. Each hour of treatment delay is associated with an 8% decrease of survival in septic shock patients. Blood culture is the gold standard diagnostic method, however, it takes more than one day to provide results. Therefore, patients receive broad-spectrum antibiotics or may not receive treatment in the initial hours. Molecular detection is an attractive solution, however, currently available tests are based on PCR amplification of bacterial genomic DNA followed by complex detection strategies. These techniques suffer from DNA contamination, lack sufficient sensitivity and are expensive. Here, we propose the development of a novel platform for rapid and inexpensive identification of microorganisms in whole blood without blood culture. The new platform will be based on Single Molecule Scanning (SM-Scanning), a novel molecular detection method in which probe hybridization to a target nucleic acid is detected without PCR amplification (Patent Pending). SM-Scanning uses a straight forward and inexpensive detection strategy. Preliminary results demonstrate that SM-Scanning can detect 5 Escherichia coli cells. In this proposal, we will demonstrate the properties of SM-Scanning by developing an assay capable of detecting microorganisms in blood samples in less than 1.5 hours with extremely high sensitivity. Aim 1 focuses on developing a rapid test capable of detecting the presence of bacteria in 5 ml whole blood samples with high sensitivity. Aim 2 focuses on developing and determining the performance of a multiplex assay capable of detecting bacteria and fungi in a single assay.