P1221 Analysis Of Oral And Intestinal Microbiome Of Korean Patients With Crohn's Disease

Abstract Background We aimed to conduct a study comparing the fecal and oral microbiomes of Korean Crohn's disease patients with those of healthy individuals. Since most of microbial study of inflammatory bowel disease patients are conducted overseas, this study would reveal if the microbiome of Korean patients and patients of other countries are the same or not. Also, since the process of fecal sample collection is inconvenient, saliva sample analysis was performed to find a relevance of disease activity. Methods This single center study recruited patients with CD between September 2022 and January 2023. At first visitation, stool collecting tube and saliva collecting tube were given to CD patient. Collected stools samples and saliva samples were sent to the environmental bioengineering laboratory in Korea University and assessed by 16S rRNA sequencing. Results 26 CD patients and 6 healthy individuals were enrolled to this study. In the comparison of helathy individual’s fecal microbiome, the flora of fecal sample of CD patients were slightly different. The diversity of microbiome was decreased in CD patients compared to healthy individuals. There were 17 species existed only in CD patient’s feces. The most frequently detected one was Ruminococcus gnavus, and the the highest abundance was Unclassified Fusobacterium. In the phylum level of bacteria, Bacteroidota, Firmicutes, and Proteobacteria were predominant. Saliva samples showed no significant difference between CD patient and control. Conclusion Fecal sampling can be usefully used as a diagnostic test technique that can reflect CD patients’ microbiota. Similar to patient in overseas, dysbiosis of fecal microbiome and abundant species were detected.