PD334 - ASSOCIATION BETWEEN GUT MICROBIOTA COMPOSITION AND PARENTERAL SUPPORT DEPENDENCE IN CHRONIC INTESTINAL FAILURE DUE TO SHORT BOWEL SYNDROME

PD334

ASSOCIATION BETWEEN GUT MICROBIOTA COMPOSITION AND PARENTERAL SUPPORT DEPENDENCE IN CHRONIC INTESTINAL FAILURE DUE TO SHORT BOWEL SYNDROME

M. Ossola¹, F. D. Merlo¹, U. Aimasso¹, E. Olimpio², I. Ferrocino², S. Bo^2,*

¹Clinical Nutrition Unit, ²University of Torino, Torino, Italy

Rationale: Intestinal adaptation in patients with chronic intestinal failure (CIF) due to short bowel syndrome (SBS) may allow weaning from parenteral support (PS). The contribution of gut microbiota to this process remains unclear. This observational study compared gut microbiota profiles in strictly matched CIF-SBS patients with identical intestinal anatomy and comparable anthropometric and clinical characteristics, stable dietary intake, and differing PS dependence.

Methods: Adult SBS patients under follow-up at our national tertiary referral center were screened. Inclusion criteria required ≥2 years of PS and the possibility of pairwise matching for anatomy and clinical features. Patients with stoma or other conditions potentially affecting microbiota composition were excluded. Six patients (three matched pairs: weaned vs non-weaned) were enrolled. Fecal samples were analyzed by 16S rRNA gene (V3–V4) sequencing.

Results: Weaned patients showed significantly higher alpha diversity compared with non-weaned patients (Shannon 6.3±1.5 vs 3.2±0.5, p=0.028; Simpson 0.94±0.07 vs 0.79±0.06, p=0.044). Beta diversity analysis demonstrated clear group separation; this effect did not reach statistical significance (p=0.10) due to the small sample size.  Non-weaned patients were dominated by Lactobacillus, Intestinibacter, Escherichia, and Bifidobacterium, whereas weaned patients exhibited enrichment of Akkermansia, Bacteroides, Blautia, Faecalibacterium, Ruminococcus, and other short-chain fatty acid–producing taxa.

Conclusion: Successful PS weaning in CIF-SBS was associated with greater microbial diversity and enrichment of commensal, metabolically favorable taxa, suggesting a potential link between gut microbiota composition and intestinal adaptation. The sample size was very small, but accurate pairwise matching reduced confounding, and results were plausible.

Disclosure of Interest: None declared