Identification of an Intestinal Microbiota Signature Associated With Severity of Irritable Bowel Syndrome

Fecal microbiota showed covariation with mucosal adherent microbiota.We confirmed the robustness of the intestinal microbial signature for severe IBS in the validation set. The signature was able to discriminate between patients with severe symptoms, patients with mild/moderate symptoms, and healthy subjects. By using this intestinal microbiota signature, we found IBS symptom severity to be associated negatively with microbial richness, exhaled CH4, presence of methanogens, and enterotypes enriched with Clostridiales or Prevotella species.