Abstract:

Objective To investigate the structural characteristics of the appendiceal contents flora in appendicitis with different pathological types in pediatric patients from a perspective of molecular biology，and to provide a new perspective for comprehensive understanding of the pathogenic bacteria associated withappendicitis in children. Methods Based on the histopathological grouping，the pediatric patients with appendicitis were divid⁃ ed intoasimple appendicitis group（n = 6）andasuppurative appendicitis group（n = 6）. The DNA from appendiceal contents was collected ，and the bacterial rRNA gene sequence V3⁃V4 high variation region was amplified and sequenced by Illumina Nova to cluster and analyze the structure，abundance and diversity inthe two groups. Results Alpha diversity analysis showedthe difference was statistically significant between the two groups（P < 0.05）， and the difference was statistically significant as comparing the abundance of bacterial flora R = 0.34（P < 0.05）. There were differences between the two groupsin appendicular tissue contents at the level of order，family，genus and species. At the genus level，Faecalibacterium and Agathobacter were predominant in the simple appendicitis group，while Bilophila was predominant in the pyogenic appendicitis group. Conclusions By analyzing the diversity of appendiceal contents flora in different pathological types in pediatric patientswith appendicitis，thedifferences in flora abundance and diversity between simple and purulent appendicitis can be found，providing afresh idea for histopathological studies onclinical appendicitis.

Key words:

children, appendicitis, 16S rRNA, pathological type, microbial community diversity