Abstract
It is unclear whether the alleged efficacy of probiotics in childhood acute gastroenteritis depends on the duration and severity of symptoms before treatment. Preplanned secondary analysis of 2 randomized placebo-controlled trials in children 3-48 months of age was conducted in 16 emergency departments in North America evaluating the efficacy of 2 probiotic products (Lactobacillus rhamnosus GG and a combination probiotic: L. rhamnosus and L. helveticus). Participants were categorized in severity groups according to the duration (<24, 24-><72, and ≥72 hours) and the frequency of diarrhea episodes in the 24 hours (≤3, 4-5, and ≥6) before presentation. we used regression models to assess the interaction between pretreatment diarrhea severity groups and treatment arm (probiotic or placebo) in the presence of moderate-to-severe gastroenteritis (modified vesikari scale score ≥9). secondary outcomes included diarrhea frequency and duration, unscheduled healthcare provider visits, and hospitalization. a total of 1,770 children were included, and 882 (50%) received a probiotic. the development of moderate-to-severe gastroenteritis symptoms after the initiation of treatment did not differ between groups (probiotic-18.4% [162 882] vs placebo-18.3% [162 888]; risk ratio 1.00; 95% confidence interval 0.87, 1.16; p="0.95)." there was no evidence of interaction between baseline severity and treatment (p="0.61)" for the primary or any of the secondary outcomes: diarrhea duration (p="0.88)," maximum diarrheal episodes in a 24-hour period (p="0.87)," unscheduled healthcare visits (p="0.21)," and hospitalization (p="0.87)." in children 3-48 months with acute gastroenteritis, the lack of effect of probiotics is not explained by the duration of symptoms or frequency of diarrheal episodes before presentation.>
