Experimental study of the influence of intestinal flora on the healing of intestinal anastomoses

Abstract

Abstract Background The beneficial effects of the normal intestinal flora on wound healing in the skin have already been confirmed, and this study attempted to elucidate the influence of the intestinal flora on the healing process in intestinal anastomoses. Methods Five groups of rats were studied: germ-free, conventional, monocontaminated with Lactobacillus acidophilus La5 or Escherichia coli X7 and ex-germ-free (conventionalized). All animals underwent ileal and colonic resections followed by anastomoses. Seven days later they were killed and the bursting pressure and hydroxyproline concentration of the anastomoses were measured. The microbiological status of the animals was confirmed weekly. Results No bacteria were detected in the germ-free rats and no other bacteria were found in the monocontaminated animals. Conventional rats had a significantly higher anastomotic bursting pressure both in the ileum compared with rats monocontaminated with L. acidophilus, and in the colon compared with germ-free rats. The ex-germ-free rats also showed a significantly higher bursting pressure than germ-free animals and rats monocontaminated with either L. acidophilus or E. coli in the ileum and colon. Conclusion The presence of the intestinal flora enhanced the healing of intestinal anastomoses. The data suggest that this effect depends on differences in the types of bacteria in the intestine.