Characteristics of intestinal flora of ileocecal region in pediatric patients with Crohn disease

Abstract

Abstract Purpose Intestinal microbiota was considered to be one of the main factors leading to changes in the immune response and had a significant correlation with Crohn disease (CD).This study aimed to reveal the intestinal microbiota profiles of Crohn's disease patients. Methods We analyzed the alterations of the gut mucosal microbiota using a 16S rRNA sequencing approach in CD patients in active stage (CD), CD patients in the remission stage (CDR) and the control group (Col). Results The results showed that there was a higher abundance of the genus Enterococcus, Lachnoclostridium and Prevotella in CD group than that in CDR and Col. Also, we found a lower abundance of the genus Ruminococcus gnavus group in CD and CDR patients, but higher in Col, indicating that Ruminococcus gnavus group was closely related to CD. Conclusions The decreased abundance of Ruminococcus gnavus may result in the reduction of mucin and subsequently lead to the degradation of the host’s ability to maintain a bacteria-free zone within the mucin layer. The increasing of Prevotella may be one of the inducing factors of Crohn's disease. Also, high level Enterococcus faecalis colonization had a significant, positive relationship with Pediatric Crohn disease activity index (PCDAI).