Probiotics are live micro-organisms that alter the enteric microflora and have a beneficial effect on health. Bacteria associated with probiotic activity have frequently been lactobacilli or bifidobacteria, but Escherichia coli and enterococcal strains have been used, as have non-bacterial organisms such as Saccharomyces boulardii.

The rationale for using probiotics in inflammatory bowel disease (IBD) is based on persuasive evidence implicating intestinal bacteria in the pathogenesis of IBD.1 ,2 The most compelling evidence is derived from animal models; despite great diversity in genetic defects and immunopathology, a consistent feature is dependency on the presence of normal enteric flora for full expression of disease. It appears that the pathogenesis of IBD, particularly Crohn's disease, involves genetically influenced dysregulation of the mucosal …