Alterations in the gut microbiotas of children with food sensitization in early life

Background: We hypothesized that food sensitization (FS) in children could be linked to specific gut microbiota. The aim of our study is to quantify and evaluate differences in gut microbiota composition between children with FS and healthy controls. Methods: A case-control study of 23 children with FS and 22 healthy children was performed. Individual microbial diversity and composition were analyzed via parallel barcoded 454 pyrosequencing targeting the 16S rRNA gene hypervariable V3-V5 regions. Results: The children with FS exhibited lower diversity of both the total microbiota (p = 0.01) and the bacterial phylum Bacteroidetes (p = 0.02). In these children, the number of Bacteroidetes bacteria was significantly decreased and that of Firmicutes were significantly increased compared with the healthy children. At the genus level, we observed significant increases in the numbers of Sphingomonas, Sutterella, Bifidobacterium, Collinsella, Clostridium sensu stricto, Clostridium IV, Enterococcus, Lactobacillus, Roseburia, Faecalibacterium, Ruminococcus, Subdoligranulum, and Akkermansia in the FS group. We also found significant decreases in the numbers of Bacteroides, Parabacteroides, Prevotella, Alistipes, Streptococcus, and Veillonella in this group. Furthermore, linear discriminant analysis (LDA) coupled with effect size measurements revealed the most differentially abundant taxa (increased abundances of Clostridium IV and Subdoligranulum and decreased abundances of Bacteroides and Veillonella), which could be used to identify FS. Conclusions: Our results showed that FS is associated with compositional changes in the gut microbiota. These findings could be useful for developing strategies to control the development of FS or atopy by modifying the gut microbiota.