Probiotics in Crohn's disease remission: a systematic review

Introduction. Crohn's disease (CD) is an inflammatory condition that can affect the entire gastrointestinal tract due to an exacerbated and inadequate immune system response. Objective. This study aimed to conduct a systematic review, through clinical trials, about the use of probiotics in humans with CD. Materials and methods. Research was carried out in the PubMed, Scopus and Science Direct databases using the keywords "Crohn's disease" and "probiotics". We conducted the review by searching clinical trials published from 2000 to December 2019. Results. Of 2,164 articles found, only nine were considered eligible for this review. The studies investigated patients with CD at different stages of the pathology, and in three studies the potential effect of probiotics in the active phase was observed; in two, in the remission phase; and in four, after intestinal surgery. The sample size of the studies ranged from 11 to 165 individuals and the age of the participants between 5 and 71 years. Gram-positive bacteria were used in six clinical interventions and in two studies yeasts were used. As for the significant results obtained with the treatment with probiotics, in one study there was beneficial clinical effects in patients and, in another, there was an improvement in intestinal permeability. Conclusion. Currently, it is not possible to establish a recommendation for probiotic therapy to control CD due to the few clinical trials with significant results. There is a need for more research on clinical intervention with probiotics in CD to clarify the action, define doses and time of use.