Characteristics Of Intestinal Flora In Children With Hand-Foot-Mouth Disease

Objective:To analyze the characteristics of intestinal microflora in the feces of children with common hand-foot-mouth disease,to preliminary explore the role of intestinal microbiota in the pathogenesis of hand-foot-mouth disease,and to provide new ideas for treatment and improvement of prognosis.Methods:30 cases of common hand-foot-mouth disease hospitalized in the Department of Infectious Diseases of the Children's Hospital of Soochow University from July 2019 to December 2019 were included in the study,and 30 cases in the same period were selected according to gender and age matching.Children with viral enteritis and 30 patients with non-intestinal diseases undergoing elective surgery were fixed as the control group.16S rDNA Amplicon Sequencing to analyze the characteristics of intestinal micro-flora in fresh feces of children with hand-foot-mouth disease in the acute phase are used,with the same detection method of rotavirus group,surgical elective surgery group intestinal micro-flora of children.The characteristics of the intestinal flora to explore the role of intestinal flora in hand-foot-mouth,and provide a more comprehensive understanding of the occurrence and development of hand-foot-mouth disease are also compared.Result:(1)Analysis of typical data:There was no statistically significant difference in age,weight and gender composition ratio among the three groups(all P>0.05),and the data among the groups were balanced and comparable.(2)Sequencing data processing and analysis:The sequences are clustered into OTUs with 97%identity,and a total of 3,320 OTUs are obtained.Species annotation of OTUs sequence,the proportion of annotation to the door level is 78.34%,the proportion of the class level is 74.91%,the proportion of the order level is 69.85%,the proportion of the family level is 64.04%,and the proportion of the genera level is 43.55%.The ratio of the level is 14.85%.(3)Quality control:The rarefaction curve of the intestinal flora of the research object indicates that as the number of sequencing increases,the curve gradually appears plateau,proving that the amount of the sequencing data is gradually reasonable;the species accumulation boxplot indicates that the curve tends to be flat,indicating that the species in this environment will not increase significantly with the increase in sample size,which further indicates that the sampling is sufficient and data processing can be performed.(4)Analysis of intestinal flora diversity:?Alpha diversity:the intestinal flora in the hand-foot-mouth disease group is lower in species richness and uniformity than the surgical elective surgery group,and higher than the rotavirus group(P<0.05);there is no difference in the number of intestinal flora in the three groups(P>0.05);?Beta diversity suggests that the composition of intestinal flora between the hand-foot-mouth disease group and the control group has a more obvious zoning trend.(5)Analysis of intestinal flora abundance results:At the phylum level,the three groups are mainly composed of Firmicutes,Proteobacteria,Actinobacteria,and Bacteroidetes.The dominant strains are the same,but the abundance accounts for the proportions are different.The highest abundance among the three groups is Firmicutes,with abundance ranging from 37.10%to 47.98%,while the rotavirus group Bacteroidetes abundance level is the lowest among the three groups;at the class level,the three groups are mainly composed of Bacteroidia,Clostridia,Gammaproteobacteria,unidentified_Actinobacteria,Bacilli,but the proportion of abundance was different.The highest abundance in the HFMD group was Bacteroidia;at the order level,the composition of the three groups of dominant bacteria begins to change,especially in the differences in the abundance of Bacteroidales and Lactobacillales from the hand-foot-mouth disease group and the rotavirus group;at the family level,the composition of the three groups of dominant bacteria also changed,especially in the Ruminococcaceae,Lachnospiraceae of the hand-foot-mouth disease group,Enterococcaceae,Streptococcaceae of the rotavirus group;at the genus level,the composition of the three groups of dominant bacteria also changes.The highest abundance is Bacteroides in the hand-foot-mouth disease group.The abundance level of Veillonella in the hand-foot-mouth disease is the highest among the three groups;at the species level,there is a difference in the composition of the intestinal flora and the abundance level among the three groups.The highest abundance in the hand-foot-mouth disease group is Escherichia coli in the hand-foot-mouth disease group.The abundance level of Veillonella ratti is the highest among the three groups.(6)Intestinal flora difference analysis:?Compared with the rotavirus group,there are 18 species with significant differences in abundance between the two groups.The abundance level of 11 species of bacteria such as Bacteroidetes,Bacteroidia,Bacteroidales,Clostridia,Clostridiales,Lachnospiraceae,Ruminococcaceae,etc.in the hand-foot-mouth disease group is significantly higher in the rotavirus group,the abundance level of 7 species of bacteria such as Bacilli,Lactobacillales,Enterococcaceae,and Enterococcus is significantly lower than that in the rotavirus group.?Compared with the surgical elective surgery group,there are 9 species with significant differences in abundance between the two groups.The abundant levels of Veillonella and Veillonella ratti in the HFMD group are significantly higher than those in the surgical elective surgery group.Clostridia,Clostridiales,Lachnospiraceae,Lactobacillales and other seven groups of abundance levels are significantly lower than the surgical elective surgery group.Conclusion:? The structure and species richness of intestinal flora in children with hand-foot-mouth disease are significantly different from rotavirus group and surgical elective operation group.? Decreased intestinal flora diversity in children with hand-foot-mouth disease may lead to weakened intestinal defense function.?Changes in the predominant genus of intestinal flora in children with hand-foot-mouth disease may be associated with the occurrence and development of hand-foot-mouth disease.