Biogeography of the human mucosal-associated microbiota

We recruited 59 controls (without structural abnormalities and gastrointestinal symptoms), 44 patients with ulcerative colitis and 31 with Crohn's disease. Biopsies from various segments of the upper (oesophagus, gastric, and duodenum) and lower (terminal ileum, right colon and rectum) gastrointestinal tract were collected. Microbial composition was assessed via 16S rRNA gene amplicon analysis and the bacterial load of the mucosal biopsies were assessed via qPCR. The MAM was examined in the context of disease status, proton pump inhibitor usage, the severity of gastrointestinal symptoms, and the symptom response to a standardized nutrient challenge.