Study On The Structure And Diversity Of Gut Microbiota In Infants With Cow's Milk Protein Allergy

1.Backgroud and Objection1.1 BackgroudCow's milk protein allergy(CMPA)is an immune-mediated adverse reaction of the body to milk proteins,which is mainly manifested in the symptoms of the digestive tract,skin and respiratory tract,and can seriously lead to backward growth and development,or even anaphylactic shock.It has become a worldwide public health problem.The pathogenesis of CMPA is still unclear.When many antigenic substances enter the body through the gastrointestinal tract,the interaction between antigens and intestinal flora,as well as between intestinal flora and the host,jointly regulate the immune system of the body,or lead to the pathogenesis of the body,or produce immune tolerance.More and more human studies have shown that the characteristics of intestinal flora in children associated with food allergy conditions have changed.The changes of intestinal flora in CMPA infants and the role of these changes in the occurrence of CMPA and immune tolerance are worthy of further clinical research.At present,there were few domestic clinical studies on the intestinal flora of infant CMPA,and the role and changes of intestinal flora in CMPA need to be further explored,so as to provide a thinking direction and clinical significance for the diagnosis and treatment of CMPA,as well as new ideas for the diagnosis and treatment of other allergic gastrointestinal diseases.1.2 ObjectiomBy measuring the differences with metagenome dection from the perspectives of structure,diversity,phylum,genus and species of gut microbiota in CMPA infants and healthy infants,to explore the role of intestinal flora in the occurrence of CMPA,and to provide theoretical basis for the prevention and treatment of CMPA.2.Method18 CMPA infants were admitted to Shenzhen Maternity and Child Health Care hospital from March 2019 to November 2019,who were from 1 to 6 months and have clinical symptoms of CMPA,then confirmed by the open food challange by the digestive specialist.During the same period,6 healthy infants were randomly selected for physical examination.The feces of 24 infants were collected for metagenome dection.3.Result3.1 There was no significant difference in the diversity of gut microbiota between the CMPA group and the healthy control group(P>0.05).However,on the whole,there was difference in gut microbiota between the two groups(P<0.05)3.2 The gut microbiota of CMPA group and healthy control group with statistically significant differences in relative abundance at the phylum level(P<0.05)was Bacteroidetes.The relative abundance of CMPA group was less than that of healthy control group.3.3 The gut microbiota with statistically significant differences in relative abundance at the genus level(P<0.05)were Bifidobacterium,Eggerthella,Butyricimonas,Parabacteroides,Prevotella,Chryseobacterium,Barnesiella,Alistipes,Pedobacter,Tannerella,Paraprevotella,Collinsella.The relative abundance of CMPA group was less than that of healthy control group.3.4 The gut microbiota with statistically significant differences in relative abundance at the species level(P<0.05)were Bifidobacterium longum,Clostridium butyricum,Bacteroides thetaiotaomicron,Bacteroides vulgatus,Lactobacillus rhamnosus,Bifidobacterium catenulatum,Bacteroides dorei,Bifidobacterium adolescentis,Eggerthella lenta,Parabacteroides distasonis,Bacteroides caecimuris,Parabacteroides sp.CT06,Collinsella aerofaciens.The relative abundance of CMPA group was less than that of healthy control group.Relative abundance of Clostridium butyricum in the CMPA group was higher than in the healthy control group3.5 There was a statistical difference in the functional composition of gut microbiota between the CMPA group and healthy control(P<0.05).4.ConclusionThere is no difference in intestinal microflora diversity between infants with CMPA and healthy infants,but the microflora structure of the two groups was different.There are significant differences in phyla,genus and species between the CMPA group and the healthy control group.The abundance of some Bifidobacterium,Bacteroides and Lactobacillus rhamnosus in the CMPA group is lower than that in the control group.The significance of the structure and diversity of intestinal flora in the study of infant with CMPA is suggested.