The fecal and mucosa adherent microbiome depends on age and disease severity in both composition and functional properties in ulcerative colitis

To date, it is unknown why the pediatric onset UC-phenotype appears to be more aggressive than that seen in adult-onset UC. To evaluate microbial differences between the two groups both longitudinal fecal samples and multi-site biopsies were collected from the patients. Fecal samples were subjected to shotgun metagenomic sequencing and biopsies to amplicon 16S rRNA gene sequencing.