Probiotics, Prebiotics, and Antibiotics in IBD

The rationale for using probiotics, prebiotics, and antibiotics in IBD is based on convincing evidence that implicates intestinal bacteria in the pathogenesis of the disease. Probiotics are “living organisms, which upon ingestion in certain numbers, exert health benefits beyond inherent basic nutrition.” Several mechanisms have been proposed to account for the action of probiotics. These include antagonistic activity against pathogenic bacteria, either by inhibition of adherence and translocation, or by production of antibacterial substances such as antimicrobial peptides and hydrogen peroxide. Probiotics also stimulate mucosal defense, both at the level of immune and epithelial function. Encouraging results have been obtained with probiotic therapy in experimental colitis. VSL#3, a highly concentrated cocktail of probiotics has been shown to be effective in the prevention of pouchitis onset and relapses. Results on the use of probiotics in UC are promising, both in terms of the prevention of relapses and the treatment of mild-to-moderate attacks. Results in Crohn’s disease are not yet clear because of conflicting data and the limited number of well-performed studies. Prebiotics are dietary substances, usually nondigestible carbohydrates, which beneficially affect the host by selectively stimulating the growth and activity of protective commensal enteric bacteria. Evidence supporting the use of these nutraceuticals in IBD is still limited. The use of antibiotics in UC is not supported by the available studies. Antibiotics have an essential role in treating the septic complications of Crohn’s disease, including intra-abdominal and perianal abscesses and perianal fistulae. The use of antibiotics in pouchitis is largely justified although proper controlled trials have not been conducted.