Probiotics for induction of remission in ulcerative colitis

BACKGROUND: Ulcerative Colitis (UC) is an inflammatory condition affecting the colon with an incidence of approximately 10-20 per 100,000 per year. No existing intervention is effective in all patients with a proportion requiring colectomy. There are significant proportion of patients who experience adverse effects with current therapies. Consequently, new alternatives for the treatment of UC are constantly being sought. Probiotics are live microbial feed supplements that may beneficially affect the host by improving intestinal microbial balance, enhancing gut barrier function and improving local immune response. OBJECTIVES: To assess the efficacy of probiotics compared with placebo or standard medical treatment (5-aminosalicylates, sulfasalazine or corticosteroids) for the induction of remission in active ulcerative colitis. SEARCH METHODS: A comprehensive search for relevant randomised controlled trials (RCT's) was carried out using MEDLINE (1966-January 2006), EMBASE (January 1985- 2006) and CENTRAL. The Cochrane IBD/FBD Review Group Specialised Trials Registrar was also searched. The Australasian Medical Index, Chinese Biomedical Literature Database, Latin American Caribbean Health Sciences Literature (LILACS), and the Japan Information Centre of Science and Technology File on Science, Technology and Medicine (JICST-E) were also used to identify abstracts. Conference proceedings from the Falk Symposium, Digestive Disease Week (DDW) and the United European Digestive Disease week were hand-searched. Authors of relevant studies and drug companies were contacted regarding ongoing or unpublished trials that may be relevant to the review. SELECTION CRITERIA: Randomised controlled trials investigating the effectiveness of probiotics compared to standard treatments in the induction of remission of active ulcerative colitis DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data for analysis. Data were analysed using RevMan 4.2.7. A formal meta-analysis was not preformed due to differences in probiotics, outcomes and trial methodology. MAIN RESULTS: None of the included studies reported any statistically significant differences in remission or clinical improvement rates between probiotic and placebo or active comparator groups. AUTHORS' CONCLUSIONS: Conventional therapy combined with a probiotic does not improve overall remission rates in patients with mild to moderate ulcerative colitis. However, there is limited evidence that probiotics added to standard therapy may provide modest benefits in terms of reduction of disease activity in patients with mild to moderately severe ulcerative colitis. Whether probiotics are as effective in patients with severe and more extensive disease and whether they can be used as an alternative to existing therapies is unknown. Further well designed, larger randomised controlled trials are needed to determine whether probiotics can be used as an alternative to current treatment modalities.