Abstract
Background: Antibiotic-associated diarrhea (AAD), defined as diarrhea that occurs in association with the administration of antibiotics and without another clear etiology, is one of the most commonly adverse drug events of antibiotics therapy. We established a diarrhea model induced by gentamycin and cefradine to investigate the microbiota characteristics in the intestinal lumen of mice with AAD and provide insights into noteworthy bacteria related to gentamicin and cefradine-associated diarrhea.Results: The number of OTUs in the model group and the normal group was 983 and 2107, respectively, and 872 identical OTUs were shared between two groups. Species richness and species diversity of intestinal microbe were altered by antibiotics administration. The dominant phyla of AAD mice were Firmicutes (52.63%) and Proteobacteria (46.37%). The abundance of 8 genera, Ruminococcus, Blautia, Enterococcus, Eubacterium, Clostridium, Coprococcus, Aerococcus, and Pseudomonas, increased significantly, and the abundance of 3 genera, Prevotella, Bacteroides, and Adlercreutzia, decreased significantly in the model group compared to those in the control group (p < 0.05). LEfSe analysis showed that Enterococcus, Eubacterium, Ruminococcus, and Blautia were the key differential genera in the model group.Conclusions: The bacterial diversity of the intestinal lumen was diminished after gentamicin and cefradine administration. The alterations in the abundance and composition of gut microbiota further led to the dysfunction of gut microbiota. More specifically, gentamicin and cefradine significantly increased the abundance of the opportunistic pathogens, of which Enterococcus and Clostridium were the most prominent and most worthy of attention.
Bacterial diversity in intestinal mucosa of antibiotic-associated diarrhea mice