Impact of prophylactic antibiotic use on the gut microbiota and antimicrobial resistance genes in healthy individuals

Seminar Details
Wednesday, April 18, 2018 - 9:00am to 10:00am


Anna Seekatz, Ph.D.
Research Investigator - Young Lab
Department of Internal Medicine - Infectious Diseases Division
University of Michigan Medical School


5623 Med. Sci. II  (Wheeler Seminar Room)

Vincent Young, M.D., Ph.D.

Antibiotic exposure is known to disrupt the gut microbiota, allowing for potential colonization with other microbes. Currently, there is a need for prospective, longitudinal studies in healthy individuals assessing the impact of antibiotics on the gut microbiota’s structure and function. To assess the impact of antibiotics on the gut microbiota, we recruited healthy adults undergoing elective orthopaedic or urologic procedures where one or more doses of perioperative antibiotics are routinely given. Up to seven stool samples from each subject were collected starting 1 month before out to 3 months after antibiotics. We used 16S rRNA gene sequencing to assess the microbiota and targeted qPCR to identify the presence of selected antibiotic resistance genes. Principal coordinates analysis of the microbiota communities revealed that individual subjects’ samples clustered together independent from antibiotic use. Minimal changes in overall alpha diversity were observed following antibiotic use; however, several individual operational taxonomic units (OTUs) classified as Lachnospiraceae members decreased after antibiotics. These trends were even more pronounced when mixed models accounting for subject-specific trends were used rather than groupwise analyses in differentiating the microbiota pre- and post-antibiotics. Antibiotic resistance genes were detected in almost all subjects, with the most notable increases observed in qnrS, vanB, and tetA genes following antibiotic use. Our data suggest that even single doses of select perioperative antibiotics can impact the microbiota, particularly individual Firmicutes members.