Abstract
Inflammatory bowel disease (IBD) consists of ulcerative colitis (UC) and Crohn’s disease (CD). The global incidence of IBD is increasing recently. Westernization is hypothesized to play role in this phenomenon. Inflammation is the basic etiology of IBD. Genetic and environmental factors are important determinants of IBD. Gastrointestinal microorganism is a component of the environmental factors. Balanced-state microorganism environment is important to maintain normal gastrointestinal function. Dysbiosis, an imbalance in beneficial and pathogenic gastrointestinal microorganism, may elicit inflammation and result in IBD. Dysbiosis causes increased pro-inflammatory activity, decreased anti-inflammatory activity, disrupted gastrointestinal mucosal barrier, and prolonged inflammation. Probiotics are hoped to mend the dysbiosis and alleviate inflammation along with disease course. Studies in human reported that administration of probiotics along with standard therapy for UC gives promising result. In contrast, probiotics have little or no positive effect in CD. Probiotics as adjunctive therapy may be considered in managing patients with UC but not with CD.

Key words: IBD, ulcerative colitis, Crohn’s disease, probiotics.