Background The precise pathogenesis of the Ulcerative colitis is still yet unknown, but one of its cause is known to be microbial dysbiosis. The mucosa-associated microbiota are more deeply involved in the pathogenesis of UC. However, the optimal sampling of mucosa-associated microbiome has yet to be investigated. In this study, we investigated the mucosa-associated microbiome in patients with ulcerative colitis, using endoscopic brush samples. We hypothesized that endoscopic brushing is precise and noninvasive method to get sample of mucosa-associated microbiome. Methods Patients with UC who visited the gastroenterology department of Korea University Anam hospital were screened for this study. Clinical data such as medical records, colonoscopy and fecal samples were reviewed. Using a stool and saliva sample collector kit respectively, the subjects provided stool and saliva samples. Brushing samples were collected during the sigmoidoscopy procedure with 3-4 brush strokes on the colon mucosa using the cytology brush. The samples were analyzed for microbiome in the Korea University Medical Center. Results From July 2022 to January 2023, we prospectively enrolled 19 patients with UC. Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria were the most common species in microbiota of brush, stool and saliva.(Fig.1-1) The microbiome between stool and brush was no significant difference in alpha and beta diversities.(Fig.1-2) However, Oral microbiome was different from stool and brush in beta diversities.(Fig.1-3) Patients were categorized into to analyze the oral microbiome. A trend was observed where increased disease severity was associated with an increase in Firmicutes.(Fig.1-4) Conclusion The microbiome of stool and brush was no significantly different. However, the novel sampling of mucosa-associated microbiome, endoscopic brush, is not inferior compared to currently used sampling of stool. Also the analysis of the oral microbiome suggested that Firmicutes could be considered a useful biomarker for assessing disease severity. Therefore, it is necessary to conduct followup research by increasing the number of subjects.

中文翻译：

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P424 使用内窥镜刷分析溃疡性结肠炎的肠道微生物群

背景 溃疡性结肠炎的确切发病机制尚不清楚，但已知其原因之一是微生物失调。粘膜相关微生物群更深入地参与UC的发病机制。然而，粘膜相关微生物组的最佳采样仍有待研究。在这项研究中，我们使用内窥镜刷样本研究了溃疡性结肠炎患者的粘膜相关微生物组。我们假设内窥镜刷牙是获取粘膜相关微生物组样本的精确且无创的方法。方法本次研究筛选了就诊于高丽大学安岩医院消化内科的 UC 患者。审查了医疗记录、结肠镜检查和粪便样本等临床数据。受试者分别使用粪便和唾液样本采集套件提供粪便和唾液样本。在乙状结肠镜检查过程中，使用细胞学刷在结肠粘膜上刷 3-4 次，收集刷牙样本。高丽大学医学中心对样本进行了微生物组分析。结果从2022年7月至2023年1月，我们前瞻性招募了19名UC患者。厚壁菌门、拟杆菌门、变形菌门和放线菌门是刷子、粪便和唾液微生物群中最常见的物种。（图1-1）粪便和刷子之间的微生物组在α和β多样性方面没有显着差异。（图1-1） 2）然而，口腔微生物组与粪便和刷子的β多样性不同。（图1-3）将患者分类以分析口腔微生物组。观察到疾病严重程度的增加与厚壁菌门的增加相关的趋势。（图1-4）结论粪便和刷子的微生物组没有显着差异。然而，与目前使用的粪便取样相比，粘膜相关微生物组的新型取样——内窥镜刷并不逊色。此外，口腔微生物组的分析表明，厚壁菌门可被视为评估疾病严重程度的有用生物标志物。因此，有必要通过增加受试者数量来进行后续研究。