The effect of vagotomy and drainage on the small bowel flora.

The incidence of small intestinal colonization in unoperated duodenal ulcer patients was low and similar to that in the normal population. The majority of patients seven to 10 days following truncal vagotomy and drainage were colonized whereas none of a control group of patients following simple closure of a perforated duodenal ulcer was colonized. In patients with pyloroplasty, this high incidence fell to control levels on average 18 months postoperatively, but in patients with a gastro-jejunostomy, the incidence remained raised probably due to the presence of the afferent loop. Only two patients developed episodic diarrhoea and there was no obvious association with small bowel colonization.