Alterations in the mucosa-associated bacterial composition in Crohn’s disease: a pilot study
OBJECTIVE To test the hypothesis that compared with controls, children with inflammatory bowel disease (IBD) exhibit differences in the relationships between gut microbiota and disease activity. STUDY DESIGN Children and adolescents (n = 69; median age, 14 years) with IBD and 25 healthy controls (median age, 14 years) were recruited for the study. The disease activity was determined according to the Pediatric Ulcerative Colitis Activity Index or the Pediatric Crohn Disease Activity Index. Cell counts of 9 bacterial groups and species in the fecal microbiota were monitored by real-time polymerase chain reaction analysis. RESULTS Although no major changes were observed in patients with ulcerative colitis, except for a decrease in bifidobacteria in the active state of IBD, children with active and inactive Crohn's disease (CD) had lower numbers of Faecalibacterium prausnitzii and bifidobacteria (P <.05), and patients with active CD had higher numbers of Escherichia coli (P <.05). CONCLUSIONS The microbiota in children with CD is characterized by decreased numbers of F praunsitzii and increased numbers of E coli.