Microbiome and Resistome of Mycobacterium ulcerans lesions

布鲁里溃疡(BU)是一种被忽视的细菌性疾病，主要发生在西非。溃烂分枝杆菌会引起严重的皮肤溃烂，主要发生在幼儿身上。选择的治疗方法是利福平和克拉霉素的抗生素联合疗法，并辅之以外科清创。治疗的成功取决于几个因素，包括受影响皮肤的大小，伤口细菌菌群的组成，以及治疗依从性。然而，尽管抗生素治疗取得了成功，但相当大一部分患者对治疗没有足够的反应，伤口愈合情况也存在很大差异。在相当多的病例中，治疗被推迟或完全失败。除了患者依从性可能较差外，BU皮损的细菌组成可能是影响愈合过程的驱动因素，以及伤口内细菌的抗药性，包括溃疡分枝杆菌。到目前为止，这些因素在受影响最严重的国家的流行区几乎没有受到关注。因此，该项目的目标是除了下一代测序分析(NGS)外，还用基于培养的方法分析BU皮损的伤口微生物组，其中元基因组分析将补充调查，以揭示全面的细菌多样性。BU患者将在加纳库马西和周边城市的七家医院登记。如果伤口不愈合，将从长达9个月的患者身上收集样本。拟议的研究将允许识别参与BU病变发展的相关细菌，以及它们的愈合过程。NGS筛查还可以识别不能用标准方法培养的细菌，而且以前没有发现与伤口愈合延迟有关的细菌。此外，基于测序的抗生素耐药性测试将得到表型耐药性筛查的支持。BU伤口的细菌组成将在尽管有足够的抗生素治疗但观察到损伤愈合较差的患者和那些对治疗有良好反应的患者之间进行比较。愈合历史长而差的人有被特殊微生物群和/或携带抗药性细菌的风险，包括溃烂分枝杆菌菌株。因此，为耐药细菌的出现做好准备对于充分应对不断变化的治疗方案是必要的。

Buruli ulcer (BU) is a neglected bacterial disease, predominantly occurring in West Africa. The causative agent Mycobacterium ulcerans induces severe ulcerative skin lesions mainly in young children. The treatment of choice is an antibiotic combination therapy of rifampicin and clarithromycin supported by surgical debridement. Treatment success depends on several factors comprising the size of the affected skin, the composition of the bacterial wound flora, and also treatment compliance. However, despite successes of antibiotic therapy, a significant proportion of patients do not respond adequately to treatment, and wound healing varies substantially. In a considerable number of cases, therapy is delayed or has failed completely. Except from possible poor patient compliance, the bacterial composition of BU lesions might be a driving factor affecting the healing process, as well as antimicrobial resistance of bacteria within the wounds including those of M. ulcerans. These factors have so far received little attention in endemic areas in the most affected countries. Therefore, this project aims to analyse the wound microbiome of BU lesions by culture-based methods in addition to next generation sequencing analysis (NGS), where metagenomic analyses will complement the investigations to uncover the full range of bacterial diversity. BU patients will be enrolled in seven hospitals of Kumasi, Ghana, and surrounding cities. Samples will be collected from patients up to 9 months if the wounds do not heal. The proposed study will allow identification of relevant bacteria involved in the development of BU lesion, and their healing processes. NGS screens may also identify bacteria that cannot be cultured by standard methods, and have previously not been associated with delayed wound healing. In addition, sequencing based antibiotic resistance tests will be supported by phenotypic resistance screens. The bacterial composition of BU wounds will be compared amongst patients where despite adequate antibiotic therapy poor healing of the lesions was observed, and those that responded well to therapy. Individuals with a long and poor healing history are at risk to be colonized by a peculiar microbial flora and/or carrying antibiotic resistant bacteria including M. ulcerans strains. Thus, preparedness for the emergence of resistant bacteria is necessary to respond adequately to changing therapy regimes.