Abstract: Objective: To determine difference of gut microbiome between infants with atopic dermatitis and health infants. Methods: The composition of gut microbiome was analyzed by pyrosequencing in fecal samples from infants with atopic dermatitis (AD group) and health infants (control group). 16S rRNA was sequenced by PacBio Sequel sequencer. Wilcoxon rank sum test was performed to compare the composition of gut microbiome at genus and species level between the two groups. α and β diversity were analyzed. LEfSe analysis was used to describe the representative differences between the two groups. Results: Thirty three infants with atopic dermatitis (AD group) and 30 health infants (control group) were included. The species abundance and evenness index of gut microbiome in AD group were lower than those in control group. There was no statistical significance (P>0.05), but there was a significant difference in the composition of gut microbiome between the two groups (P=0.032). LEfSe analysis showed that Citrobacter freundii and Klebsiella oxytoca were significantly increased in AD group compared with the control group at genus and species level, while Streptococcus, Veronococcus, Macrospherococcus, Lactobacillus salivary, Clostridium tertii and Clostridium innocuum were significantly increased in control group compared with the AD group. Conclusion: The species abundance and biodiversity of intestinal flora in AD infants are different from those in normal infants.

Key words: infant, atopic dermatitis, gut microbiome