Assessing Gut Microbiome Alterations in Children With Allergic Rhinitis: Associations With Allergen-Specific IgE Levels and Sensitization Patterns.

Background: The relationship between gut microbiota composition and allergen exposure in children with allergic rhinitis (AR) remains insufficiently explored, particularly concerning variations in gut microbiota at different allergen-specific IgE (sIgE) levels and the distinction between monosensitization and polysensitization to allergens.

Methods: We employed metagenomic shotgun sequencing to compare the fecal microbiota of 50 healthy controls (HC) to 88 children with AR induced by house dust mites (HDM-AR). We further examined differences in gut microbiota among HDM-AR subgroups with extremely high house dust mite-sIgE (EH-HDM), high HDM-sIgE (H-HDM), as well as between monosensitized (mono-HDM) and polysensitized (poly-HDM) individuals.

Results: While no significant differences in overall gut microbiome diversity were observed between the HC and HDM-AR groups, a notable increase in the relative abundance of Streptococcus sanguinis within the genus was identified in children with AR. Further analysis revealed a significant enrichment of the Streptococcus genus in the EH-HDM group, particularly highlighting an increased relative abundance of the Streptococcus salivarius. Functional gene analysis via KEGG pathways indicated substantial enrichment in the salivary secretion pathway. Additionally, in comparisons among the HC, mono-HDM, and poly-HDM groups, Streptococcus salivarius emerged as the key differential species, showing a marked increase in the mono-HDM group.

Conclusion: Our study suggests that specific bacterial strains, particularly Streptococcus salivarius, may be potential biomarkers for assessing varying degrees and patterns of HDM sensitization. These findings open the avenues for developing targeted interventions aimed at mitigating the pathophysiology of AR.