Assessment of microbiome variation during the perioperative period in liver transplant patients: a retrospective analysis.

Understanding the composition of the microbial populations in the intestines of liver transplant patients is important to preventing postoperative infection. We investigated the relationship between the risk of postoperative infection and variation in the predominant fecal microbial composition during the perioperative period. We prospectively analyzed the predominant intestinal microbiome of five asymptomatic adult carriers of hepatitis B virus (as controls without any antibiotics) at four weekly follow-up visits and 12 patients before operation and at three weekly postoperative follow-up visits within the first month. Analysis was by denaturing gradient gel electrophoresis (DGGE) and sequencing with digital processing of DGGE profiles using BioNumerics software. Our results showed that the predominant intestinal microbial diversity decreased substantially in eight patients during the perioperative period. Among these, five patients experienced infection with a postoperative hospital stay of more than 30 days. The rest of the four patients who experienced shorter postoperative hospital stays showed only slight variation in predominant intestinal bacterial composition and temporal stability similar to asymptomatic controls. Postoperative fecal DGGE profiles showed mostly bands assigned to Bacteroides and Firmicutes. We conclude that an empiric prophylaxis strategy that destructs gut microecological balance will not be effective in reducing the risk of postoperative infection. Instead, the destruction of intestinal microbiota might result in the appearance of opportunistic pathogens such as Bifidobacterium dentium which rarely appears in the intestinal DGGE profiles of normal humans. Cognizance of the variation of intestinal microbial profiles during the perioperative period is a critical aspect of caring for liver transplant recipients.