Background : Human gut microbiome is a huge community of microorganisms. Recent studies have revealed complex interaction between the human hosts and the microbiome, but the clinical importance of postoperative dysbiosis is still poorly understood. Pancreaticoduodenectomy significantly alters postoperative gut microbiome, but quantitative data remains scarce for this concept.

Methods : To analyze postoperative gut microbiota and the effect of red ginseng on microbiome alteration, we conducted a double blinded randomized controlled trial as a pilot study. The patients who underwent pylorus-preserving pancreaticoduodenectomy in Gangnam Severance Hospital were randomly assigned to red ginseng and the control group. The trial group took red ginseng pills regularly for 3 months after the surgery. Fecal samples were collected from each patient before and 3 months after the surgery respectively. Gut microbiome was analyzed using 16S rRNA sequencing, and alpha diversity, microbiome composition were calculated.

Results : There were no differences in the alpha diversity indices between overall postoperative microbiome of red ginseng group and the control. However, in the individual’s pre- and postoperative diversity comparison, red ginseng group showed no significant change in majority of alpha diversity indices, but in the control, several alpha diversity indices were significantly decreased postoperatively. In genus level, in postoperative samples, Lactobacillus composition ratio increased postoperatively in Red ginseng group (p=0.012). Bifidobacillus, Clostridium, Escherichia and Staphylococcus showed no significant difference between two groups.

Conclusions : Gut microbiota diversity was decreased and altered after PPPD. Red ginseng showed a potential as a prebiotics improving gut microbiome balance in postoperative patients