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A single, peri-operative antibiotic can persistently alter the post-operative gut microbiome after Roux-en-Y gastric bypass. Surg Endosc 2022 Jun 29



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INTRODUCTION: Roux-en-Y gastric bypass (RYGB) significantly alters the gut microbiome and may be a mechanism for post-operative cardiovascular disease improvement. We have previously found an association between the class of peri-operative, intravenous antibiotic administered at the time of RYGB and the resolution rate of hypertension suggesting the gut microbiome as a mechanism. In this study, we performed a prospective study of RYGB to determine if a single intravenous antibiotic could alter the gastrointestinal microbial composition.

METHODS: Patients undergoing RYGB were randomized to a single, peri-operative antibiotic of intravenous cefazolin (na??=a??8) or clindamycin (na??=a??8). Stool samples were collected from four-time points: 2 weeks pre-op (- 2w), 2 days pre-op (- 2d), 2 weeks post-op (+a??2w) and 3 months post-op (+a??3m). Stool samples were processed for genomic DNA followed by Illumina 16S rRNA gene sequencing and shotgun metagenomic sequencing (MGS).

RESULTS: A total of 60 stool samples (- 2w, na??=a??16; - 2d, na??=a??15;a??+a??2w, na??=a??16;a??+a??3m, na??=a??13) from 16 patients were analyzed. 87.5% of patients were female with an average age of 48.6a??A?a??12.2A years and pre-operative BMI of 50.9a??A?a??23.3A kg/m2. RYGB induced statistically significant differences in alpha and beta diversity. There were statistically significant differences in alpha diversity ata??+a??2w and beta diversity ata??+a??3m due to antibiotic treatment. MGS revealed significantly distinct gut microbiota with 11 discriminatory metagenomic assembled genomes driven by antibiotic treatment at 3 months post-op, including increased Bifidobacterium spp. with clindamycin.

CONCLUSION: RYGB induces significant changes in the gut microbiome at 2A weeks that are maintained 3A months after surgery. However, the single peri-operative dose of antibiotic administered at the time of RYGB induces unique and persisting changes to the gut microbiome that are antibiotic-specific. Increased Bifidobacterium spp. with clindamycin administration may improve the metabolic efficacy of RYGB when considering gut-microbiome driven mechanisms for blood pressure resolution.

Author List

Fernando DG, Saravia FL, Atkinson SN, Barron M, Kirby JR, Kindel TL


Tammy Lyn Kindel MD, PhD Associate Professor in the Surgery department at Medical College of Wisconsin
John Kirby PhD Chair, Center Associate Director, Professor in the Microbiology and Immunology department at Medical College of Wisconsin