Dietary fructans may worsen gastrointestinal symptoms in children with irritable bowel syndrome (IBS). The aim of the study was to determine whether gut microbiome composition and function are associated with childhood IBS fructan-induced symptoms. The faecal samples from 38 children aged 7-17 years were analyzed for fructan sensitivity.
At baseline, 17 fructan-sensitive (vs 21 fructan-tolerant) subjects had lower alpha diversity (q < 0.05) and were enriched in the genus Holdermania. In contrast, fructan-tolerant subjects were enriched in 14 genera from the class Clostridia. During the fructan diet, fructan-sensitive (vs tolerant) subjects were enriched in both Agathobacter (P = 0.02) and Cyanobacteria (P = 0.0001). In contrast, fructan-tolerant subjects were enriched in three genera from the Clostridia class. Comparing the fructan with maltodextrin diet, fructan-sensitive subjects had a significantly increased relative abundance of Bifidobacterium (P = 0.02), while fructan-tolerant subjects had increased Anaerostipes (P = 0.03) during the fructan diet. Only fructan-sensitive subjects had a trend towards increased predicted β-fructofuranosidase during the fructan vs maltodextrin diet.
Conclusion: Fructan-sensitive children with IBS demonstrate different distinct gut microbiome signatures. These microbiome signatures may be used for IBS diagnostics.