Effects of the enteral administration of Bifidobacterium breve on patients undergoing chemotherapy for pediatric malignancies.

PURPOSE: Probiotics are expected to be effective in prophylaxis of infection in cancer patient, since infections in neutropenics are mainly caused by endogenous flora through the intestinal mucosa. However, the experience with the use of probiotics in immunocompromised patients is limited, and precise fecal bacteria analysis has not been reported. The aim of the study was to evaluate the effects of the enteral administration of the probiotic, Bifidobacterium breve strain Yakult, on its ability to prevent infection, fecal micro flora, and intestinal environments in cancer patients on chemotherapy. METHODS: A placebo-controlled trial was performed at Juntendo University Hospital. Patients with malignancies admitted for chemotherapy (n = 42) were randomized into two groups receiving probiotic or placebo. The effects on infectious complications, natural killer cells, fecal micro flora, fecal organic acid concentrations, and fecal pH were studied. RESULTS: The frequency of fever and the use of intravenous antibiotics were lower in the probiotic group than the placebo group. The probiotic administration enhanced the habitation of anaerobes. Disruption of the intestinal microbiota after chemotherapy such as the increase in the population levels of Enterobacteriaceae was observed at more pronounced manner in the placebo group in comparison to the probiotic group. The concentrations of total organic acids were maintained most of the time at the normal level, which constantly maintained the pH below 7.0 only in the probiotic group. CONCLUSION: These data, although based on a limited number of patients and samples, suggest that administration of B. breve strain Yakult could be an effective approach for achieving clinical benefits in immunocompromised hosts by improving their intestinal environments.