Early-life Gut Microbiota in Food Allergic Children and Its Impact on The Development of Allergic Disease

Abstract Background: The prevalence of food allergy (FA) has been increasing steadily over the past 2 decades to 3 decades, with diversified symptoms and increasing severity. The long-term outcome will affect the growth and development of children, and it may be associated with inflammatory bowel disease. However, its pathogenesis remains unclear. Previous studies have shown that early infancy is a crucial time when gut microbiota has an impact on the development of food allergy. However, there is no unified perspective on the characteristics on dysbiosis in early life link between dysbiosis and the future of allergic diseases. Objective: We investigated the association between composition in gut microbiota in early life and long-term clinical manifestations in children with food allergy. Methods: In this study, 16S rDNA gene high-through sequencing method was used to analyze the composition of gut microbiota in children with food allergy in early life in southern Zhejiang, and the clinical manifestations were followed up for 2 years to analyze the influence of gut microbiota changes in early life on the later clinical manifestations. Results: we found that the diversity of gut microbiota in children with food allergy did not change, but the abundance of microbiota changed. The bacterial markers of food allergy may be Akkermansia, Parabacteroides, Blautia and Escherichia-Shigella, the lack of gut microbiota many be Bifidobacteriumand Clostridium. After two years，two of the ten children with food allergy still had symptoms of food allergy, the intestinal flora of these two cases in early childhood showed an increase in Escherichia-Shigella and a decrease in Bifidobacterium, The other eight cases had remission of allergic symptoms. Conclusion: We concluded that food allergy is not associated with intestinal flora diversity. Most of the symptoms of food allergy can be relieved by the age of 3 years old, which is related to the composition of early intestinal flora. Escherichia-Shigellaand Bifidobacterium may affect the prognosis of food allergy.