BACKGROUND AND AIMS Post-dysenteric irritable bowel syndrome (PD-IBS) develops in up to 25% of patients followingCampylobacter enteritis. Our aim was to define the pathological basis of this subgroup of IBS.

RESULTS In group 1, enteroendocrine cell (EC) numbers were markedly increased initially and at six and 12 weeks (p<0.001) compared with controls. Gut permeability, as assessed by the lactulose/mannitol ratio, was significantly elevated, initially and at 12 weeks (p<0.005). CD3, CD4, and CD8 lymphocyte counts in the lamina propria and intraepithelial lymphocytes (IEL) were significantly increased initially compared with controls. At visit 1, EC numbers were positively correlated with CD3 counts (r=0.6, p=0.01). At one year, seven subjects (five with persistent loose stools) had rectal biopsies which showed significantly elevated EC, CD3, and IEL counts. In group 2, EC and IEL counts were significantly increased compared with controls (p<0.001), as was gut permeability (p<0.01).

CONCLUSION Increased EC, T lymphocytes, and gut permeability are acute changes followingCampylobacter enteritis which can persist for more than a year and may contribute to PD-IBS.