IDDF2019-ABS-0184 Role of adherent-invasive E. coli in inflammatory bowel disease – epidemiology, genetics and therapeutics

Background Adherent-invasive Escherichia Coli (AIEC) colonizes mucosa of patients with Crohn’s disease (CD). Fecal microbiota transplantation (FMT) has been reported to be effective in treating CD but the response rates are variable. We investigated the prevalence of AIEC in Chinese population and explored the impact of AIEC on FMT efficacy. Methods AIEC strains were isolated from ileal tissues of Chinese Crohn’s disease patients (n=64) and healthy subjects (n=53) by selection culture and protection assay in Intestine-407 cell lines and their genomes analysed. Effect of AIEC on FMT was assessed in C57BL/6 wild type DSS-colitis model. Level of AIEC colonization was assessed by selective culture and Fluorescence in situ hybridization. Human ileal tissue and mice feces were collected for 16S rRNA sequencing. Results Prevalence of AIEC was significantly higher in mucosa of CD subjects than healthy controls (p Conclusions AIEC is a risk factor for CD in the Chinese population. The presence of AIEC was sufficient to compromise the efficacy of FMT by hindering the engraftment of beneficial bacteria, leading to incomplete recovery of inflammation.