Impact of age and sex on the composition and abundance of the intestinal microbiota in individuals with and without enteric infections

Purpose: The intestinal microbiome is critical for human health and preventing colonization by enteric pathogens. There are notable differences in the microbiota composition among individuals with and without enteric infections, though the impact that age and gender has on the composition and abundance of intestinal microbes is not known. Methods: A comparative 16S rRNA gene sequencing study was performed on stool DNA from 200 patients with enteric infections and 75 healthy family members representing both sexes and multiple age groups. Results: Microbial community profiles were affected by age and sex in patients with enteric infections and their healthy family members. Overall, we observed an increase in Bacteroides abundance and decrease in Escherichia abundance with age, though these differences were most apparent for patients with enteric infections. Genus Bacteroides was also higher in female communities while Escherichia predominated in males. Conclusions: Because Escherichia abundance was previously linked to symptom severity, children with enteric infections may be most susceptible to severe disease outcomes due to high and low abundance of Escherichia and Bacteroides, respectively. Future studies should focus on classifying specific differences in the microbiome using metagenomics and identifying novel methods aimed at shifting the intestinal microbiome to a healthy state. (C) 2016 Elsevier Inc. All rights reserved.