The Role of Novel Bacteria in Male Urethritis

描述（由申请人提供）：尿道炎是最常见的男性生殖道综合征，但一旦淋病被占，高达50%的非淋菌性尿道炎（NGU）病例没有已知的病因，表明存在隐匿性病原体。新的宏基因组方法在识别以前未识别的生物体方面非常有效。广谱核糖体RNA基因PCR是发现细菌病原体的有力技术，但灵敏度低于靶向种特异性PCR，因此两种方法都需要。利用这些技术，Fredricks及其同事最近通过宽范围rRNA基因PCR在细菌性阴道病（BV）妇女中鉴定出16种新识别的细菌。使用更灵敏的种特异性定量PCR（qPCR）测定，这些新型细菌中有7种与BV显著相关（Fredricks，NEJM 2005），5种（BV相关细菌[BVAB] 2、BVAB 3、Leptotrichia/Sneathia、阴道变形菌和Megasphaera 1型）与宫颈炎相关，使其成为强候选尿道病原体。鉴于NGU相对常见的性质，高比例的不明原因的病例和多种病因的可能性，我们提出了一个2层的方法来确定新的尿道病原体在最近完成的病例对照研究。在病原体发现活动中，我们建议使用广泛的16 S rRNA基因PCR与焦磷酸测序来描述和比较136例男性特发性尿道炎和136例男性非尿道炎的尿道细菌生物群。在一个更直接的方法，我们建议描述5个新的候选细菌病原体（BVAB 2，BVAB 3，Leptotrichia/Sneathia物种，Megaspaera 1型，A.阴道），重点是评估它们与NGU的关联。我们还将评估与新细菌检测相关的行为和临床特征，包括与NGU相关的任何微生物对NGU标准抗菌治疗的临床反应。 公共卫生相关性：该项目将揭示一个潜在的额外的生态位的新细菌，首先在妇女中发现，并可能确定以前未知的病因NGU。它将首次确定与男性感染这些细菌相关的行为和临床特征，并提供关于NGU标准疗法对这些新型细菌的疗效的初步数据。总之，这些数据可能使我们能够更准确地确定病因，更有效地治疗这种常见的男性生殖道疾病综合征。

DESCRIPTION (provided by applicant): Urethritis is the most common male reproductive tract syndrome, yet once gonorrhea is accounted for, up to 50% of non-gonococcal urethritis (NGU) cases have no known etiology, suggesting the presence of occult pathogens. New metagenomic approaches have been extremely effective in identifying previously unidentified organisms. Broad range ribosomal RNA gene PCR is a powerful technique for bacterial pathogen discovery, but is less sensitive than targeted species-specific PCR; thus both approaches are required. Using these techniques, Fredricks and colleagues recently identified 16 newly recognized bacteria among women with bacterial vaginosis (BV) by broad range rRNA gene PCR. Using more sensitive species-specific quantitative PCR (qPCR) assays, 7 of these novel bacteria were significantly associated with BV (Fredricks, NEJM 2005) and 5 (BV-associated bacterium [BVAB] 2, BVAB3, Leptotrichia/Sneathia, Atopobium vaginae, and Megasphaera type 1) were associated with cervicitis, making them strong candidate urethral pathogens. Given the relatively common nature of NGU, the high proportion of unexplained cases and the possibility of multiple etiologies, we propose a 2-tiered approach to identify novel urethral pathogens within a recently completed case-control study. In pathogen discovery activities we propose to use broad range 16S rRNA gene PCR with pyrosequencing to describe and compare the urethral bacterial biota in 136 men with idiopathic urethritis to that in 136 men without urethritis. In a more directed approach, we propose to describe the epidemiology of 5 novel candidate bacterial pathogens (BVAB2, BVAB3, Leptotrichia/Sneathia species, Megasphaera type 1, A. vaginae) in men using species-specific qPCR assays, focusing on evaluating their association with NGU. We will also evaluate behavioral and clinical characteristics associated with detection of novel bacteria, including the clinical response of any organisms associated with NGU to the standard antimicrobial therapies for NGU. PUBLIC HEALTH RELEVANCE: This project will shed light on a potential additional ecologic niche for novel bacteria that were first identified in women and may identify previously unknown etiologies of NGU. It will identify behavioral and clinical characteristics associated with infection with these bacteria in men for the first time, and provide preliminary data on the efficacy of the standard therapies for NGU against these novel bacteria. Taken together, these data may allow us to more accurately determine the etiology of and more effectively treat this common male reproductive tract disease syndrome.