Background: The aim of this study was to compare the effect of infant formula and the same formula subjected to microbial fermentation (yogurt) on the duration of diarrhea in young children with acute watery diarrhea, with or without reducing substances in stools.
Methods: One hundred twelve well-nourished children, aged 3 to 24 months, who were admitted to the hospital with acute watery diarrhea were included in a randomized trial. After appropriate rehydration, they were fed either an infant formula (group M, n = 56) or the same formula fermented with Lactobacillus bulgaricus and Streptococcus thermophilus (group Y, n = 56). The two feedings were comparable in lactose concentration (40 to 42 g/L), pH 4.5, flavor, and texture. The groups were subdivided into those with or without reducing sugars in stools at presentation. The presence of reducing sugars in stool was used as a marker of carbohydrate malabsorption.
Results: Group M and group Y had comparable clinical characteristics at admission, including the number of patients with reducing sugars in stools (n = 31 in group M and 27 in group Y). The success rate (cessation of diarrhea and appropriate weight gain 7 days after enrollment into the study) was similar in both groups (82% in group M vs. 84% group Y). Clinical failure was 3.6% in both groups. The percentage of patients withdrawn from the study for medical reasons (5.4% in group M vs. 7.1% in group Y) or withdrawn at the parents' request (8.9% in group M vs. 5.4% in group Y) was similar. Duration of diarrhea and number of stools were significantly less in group Y compared with group M. Forty-eight hours after inclusion, diarrhea was still present in 62% of group M versus in 35% of group Y (P < 0.002). In children with reducing sugars in stools, the rate of success (82%) was similar in groups M and Y, but the duration of diarrhea and number of stools per day were significantly decreased in group Y. Forty-height hours after inclusion, diarrhea was still present in 75% of group M patients and in 20% of group Y patients who had reducing substances in the stool.
Conclusion: Young children with acute watery diarrhea, without malnutrition or associated disease, can be equally well treated with feeding of either infant formula or yogurt. Yogurt feeding is associated with a clinically relevant decrease in stool frequency and duration of diarrhea in children who have reducing sugars in stools.