Gut Microbiota Perturbation Are Linked to Endoscopic Severity of Diverticular Disease

Abstract

Background and Aims: It is not known whether the gut microbiota (GM) may vary according to the endoscopic severity of diverticular disease (DD). We aimed to profile the GM in DD patients according to the severity of the diverticular inflammation and complication assessment (DICA) classification (DICA 1 vs. DICA 2 vs. DICA 3).

Methods: We retrospectively assessed the GM in a population of patients with DD. We analyzed stool samples collected by fecal swab for microbiological studies. Among them, we identified DD patients in whom DD was scored according to DICA classification. The severity of the abdominal pain was measured using a 10-point visual analogue scale (VAS).

Results: The GM of 71 DD patients [49 (69.0%) were scored as DICA1, 18 (25.4%) as DICA2, and 4 (5.6%) as DICA3 was analysed. The three groups did not differ in alpha diversity, but significantly separated in the PCoA of beta diversity (p=0.018). Taxonomically, DICA1 group was characterized by higher relative abundances of the phylum Actinobacteriota, the families Erysipelatoclostridiaceae and Bacteroidaceae, and the genera Lachnospiraceae ND3007 group and Bacteroides (p≤0.1); DICA2 group was mainly discriminated by higher proportions of Streptococcaceae (p=0.018); DICA3 group was mainly discriminated by the phylum Bacteroidota, the families Prevotellaceae and Succinivibrionaceae, and the genera Prevotella, Alloprevotella and Dialister (p≤0.045). Stratifiyng patients by abdominal pain severity, only for the DICA2 group the PCoA of beta diversity showed a significant separation between the moderate and severe groups (p=0.024), with the latter also showing higher alpha diversity (p=0.05). Taxonomically, the severe group was enriched in the families Enterobacteriaceae and Erysipelotrichaceae, and the genera Megasphaera and Veillonella, while depleted in Sutterellaceae and Blautia compared to the moderate group (p≤0.08).

Conclusions: GM in DD may vary according to endoscopic disease severity and clinical characteristics. Such associations may improve patient stratification and clinical management.