The role of probiotics and prebiotics in pediatric practice.

OBJECTIVE To review the effects of probiotics and prebiotics in clinical pediatric practice. SOURCES MEDLINE was searched, especially for articles that addressed their practical application, in the form of reviews, clinical trials and meta-analyses. Articles that had already been analyzed by the authors were also included. SUMMARY OF THE FINDINGS Scientific literature on probiotics and prebiotics has remarkably increased in the last 10 years. Their mechanisms of action have been experimentally investigated. Studies indicate that probiotics can act by competing with pathogens, modifying the intestinal environment by reduction in pH, as a result of fermentation products, interacting and modulating local and systemic inflammatory and immune response, among others. Clinical trials and meta-analyses show that probiotics seem to contribute towards the prevention of acute diarrhea and of antibiotic-associated diarrhea, in addition to shortening the duration of acute diarrhea. However, the data are inconsistent and there are no studies confirming their efficacy in terms of cost-benefit ratio. Preliminary studies show that probiotics in early life can reduce the occurrence of atopic dermatitis. The addition of prebiotics to infant formulas is associated with the change in the profile of the intestinal microbiota compared to infants fed milk formulas without prebiotics. CONCLUSIONS Evidence indicates that new studies should be carried out about probiotics, prebiotics and symbiotics. The specific clinical effects that each probiotic or prebiotic may cause must be considered.