Probiotics for induction of remission in Crohn's disease

Crohn's disease has a high morbidity and there is no known cure. Current treatments have multiple side effects and an effective treatment with minimal side effects is desired. Probiotics have been proposed as such a treatment but their efficacy is undetermined. There is some evidence that probiotics are effective in other conditions affecting the gastrointestinal tract and they are popular with patients. They are thought to work through competitive action with commensal and pathogenic flora, influencing the immune response.

To determine if there is any evidence for the efficacy of probiotics for the induction of remission in Crohn's disease.

The Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1, 2007), MEDLINE (1966 to 2007), Excerpta Medica/EMBASE (1974 to 2007), CINAHL (1982-2007) and the Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Group Specialised Trial Register were searched. Manufacturers of probiotics were also contacted to identify any unpublished trials. References of trials were also searched for any additional trials.

Randomised controlled trials (RCTs) that compared probiotics against placebo or any other intervention for the induction of remission in Crohn's disease were eligible for inclusion.

Data extraction and assessment of methodological quality of included studies were independently performed by two authors. The main outcome measure was the occurrence of clinical remission. Odds ratios and 95% confidence intervals were calculated for dichotomous outcomes.

One small study (n = 11) met the inclusion criteria and was included in the review. There were some methodological concerns with this study. Four of 5 patients in the probiotic group achieved remission compared to 5 of 6 in the placebo group (OR 0.80; 95% CI 0.04 to 17.20).

There is insufficient evidence to make any conclusions about the efficacy of probiotics for induction of remission in Crohn's disease. There is a lack of well designed RCTs in this area and further research is needed.