Effectiveness and safety of probiotic preparations in clinical treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterized by an aggressive immune response to luminal antigens including those of commensal microbiota, which are essential for intestinal homeostasis and appear to play a role in tolerance and immunity. Its disturbances can result in intestinal dysbiosis and the development of disease. The precise role of luminal bacteria in the pathogenesis of IBD has yet to be elucidated; however, considerable evidence implicates changes to bacterial communities associated with the gut mucosa in the disease state. It is also well known that beneficial microbes can confer a functional health benefit to the host. We analysed the effectiveness of probiotics to relieve symptoms in patients suffering from IBD. Using the Medline database and manually searching articles, we reviewed clinical trials performed with probiotics and lactic acid bacteria as supportive or alternative IBD treatments. The article summarizes IBD microenvironment and the efficiency of probiotic preparations in attenuating the symptoms of Crohn's disease, ulcerative colitis, and pouchitis. The safety of probiotic intake is also analyzed based on existing outcomes of clinical trials and case reports. Strong evidence exists that probiotics are effective as supportive therapy for IBD; however, only a few preparations have well documented efficiency and safety. Clinical studies demonstrated that probiotics were more effective in preventing recurrence of the disease symptoms than in the management of its active stage. Some products may increase the risk of complications in specific patient groups; therefore, the use of probiotics should be considered with caution in the case of severe active IBD, especially with disrupted mucosa.