Review article: Intestinal permeability in Crohn's disease.

Measurements of intestinal permeability (IP) may help in determining susceptibility for the development of Crohn's disease or for imminent relapse in patients with the disease. It is now apparent that a subset of patients at high risk for the development of Crohn's disease have either increased baseline IP or an exaggerated response to environmental agents that increase IP. These, coupled with observations that increased IP in patients at risk for the development of Crohn's disease is associated with an abnormal immunological phenotype, lend support to the hypothesis that increased IP is a very early event in the genesis of Crohn's disease.