Introduction: In children with acute leukemia, gut microbiota is modified secondary to chemotherapy administration, leading to gastrointestinal side effects. Probiotics are microorganisms that can restore gut microbiota and may help alleviate gastrointestinal symptoms. The aim of this pilot study was to assess the effects of probiotic supplementation on chemotherapy-induced gastrointestinal side effects in children with acute leukemia (AL). Methods: In this randomized pilot study, patients under 17 years of age diagnosed with AL who were on remission induction or remission reinduction chemotherapy were randomly assigned to receive probiotic supplementation (a concentration of 5×109 CFU per sachet was administered at a standard dose twice daily, by mouth) or no probiotic supplementation. The primary endpoint was the prevalence of gastrointestinal side effects. Vomiting, nausea, flatulence, dyspepsia, diarrhea, constipation, abdominal pain, and abdominal distention were assessed in both groups. Results: Gastrointestinal side effects were less prevalent in the probiotic group, and 3 of the 8 gastrointestinal side effects (nausea, vomiting, and abdominal distension) significantly decreased in the probiotic group (P<0.05). We found for diarrhea a relative risk of 0.5 (95% confidence interval [CI], 0.2-1.2; P=0.04); for nausea an RR of 0.5 (95% CI, 0.4-0.8; P=0.04) and for vomiting an RR of 0.4 (95% CI, 0.2-0.9; P=0.04). Conclusions: Daily supplementation with Lactobacillus rhamnosus reduced chemotherapy-induced gastrointestinal side effects in children with AL.

Introduction: During the administration of antineoplastic drugs, acute complications because of toxicity occur, determining their hospital readmission, visits to the emergency department, use of antimicrobials, and possibilities of presenting systemic infections, impacting on their life quality. Methods: Through a prospective cohort, 60 children with acute lymphoblastic leukemia were followed-up for 30 days after the hospital discharge because of chemotherapy administration, those patients were previously included in a single-blinded study in which 30 (group 1) received Lactobacillus rhamnosus GG probiotic during the administration of chemotherapy. The remaining 30 patients did not receive probiotics (group 2). There were evaluated gastrointestinal symptoms, such as diarrhea, dyspepsia, abdominal distension, meteorism, constipation, nausea, and vomit, development of infections, antibiotic use, number of emergency department visits, number of hospitalizations, and sepsis diagnosis. Statistical Analysis: To assess the impact of the use of probiotics, the difference in proportions between both study groups was evaluated. Results: Gastrointestinal manifestations (nausea, vomiting, diarrhea, constipation) occurred in 30% of patients in group 1 versus 63% of group 2 (P=0.009). Nine of 30 patients (30.0%) in group 1 went to the emergency room, versus 33.3% of group 2 (P=0.7). Antimicrobials were used in 8 subjects (26.6%) in group 1 versus 6 subjects (53.3%) in group 2 (P=0.03) suspected of an infectious disease. Four (13.3%) group 1 patients were hospitalized versus 30% of group 2 (P=0.1). Two subjects (6.6%) in group 1 had sepsis versus 7 (23.3%) in group 2 (P=0.07). Conclusions: The results indicate that the use of probiotics can be a great alternative in the improvement of gastrointestinal symptoms and the adverse effects associated with chemotherapy.