Randomized, double-blind clinical trial of a lactose-free and a lactose-containing formula in dietary management of acute childhood diarrhea.

BACKGROUND: Refeeding of artificially fed infants with lactose-containing formula after oral rehydration therapy in the treatment of acute diarrhea was concluded to be indifferent to non-lactose formula by a meta-analysis. In Thai as well as Asian infants and children with low lactase level from genetically determinant and with rotavirus infection, lactose malabsorption is most likely to occur and cause delayed recovery. The aim of this study was to compare the effect of a lactose-free and a lactose-containing formula in dietary management of acute childhood diarrhea.

PATIENTS AND METHOD: A randomized, double-blind clinical trial of 80 male children, formula-fed, aged 3 to 24 months, admitted with acute watery diarrhea and mild or moderate dehydration, was carried out. All children received oral rehydration therapy for the first 4 hours. After appropriate rehydration, they were fed either a lactose-free formula (Dumex Lactose-Free Formula; treatment group, n = 40) or a lactose-containing formula (Dumex Infant Formula; control group, n = 40) in adjunction with oral rehydration solution. In addition, the infants were fed rice gruel as tolerated. Comparisons of duration of diarrhea, weight gain, vomiting, biochemical changes, stool frequency and weight and unscheduled intravenous fluid were made.

RESULTS: Three children (2 treatment, and 1 control) dropped out from the study. The total number of unscheduled intravenous infusions were 6 of 80 children (7.5%), including 2 (5.0%) in the treatment group and 4 (10.0%) in the control group. Three children in the control group did not resolve from diarrhea within 7 days of treatment. Rotavirus was identified in approximately 50% of the children in each group. Using survival analysis, the median duration of diarrhea was significantly shortened by 20.5 hours in the treatment group compared to the control group (77.0 hours in the treatment group vs 97.5 hours in the control group; P = 0.002). Significantly decrease in stool frequency and increase in percent weight gain were seen in the treatment group at 24 hours. Moderate acidosis cleared up to near normal at 24 hours in the treatment group but acidosis persisted in the control group. In the rotavirus diarrhea subgroup, moderate acidosis turned to be mild in treatment group, but acidosis was unchanged with increased plasma chloride level in the control at 24 hours thus suggesting that the children in the control group might have lactose malabsorption and osmotic diarrhea. Duration of rotavirus diarrhea was shortened 23.6 hours in treatment group compared to the control (P = 0.0034).

CONCLUSIONS: In this study, lactose-free formula was shown to be effective in the dietary management of acute childhood diarrhea. Duration of diarrhea was shortened, weight gain was better, and stool frequency was less when compared to lactose-containing formula. Moderate acidosis cleared up spontaneously at 24 hours. Unscheduled IV could be decreased by 50%. Children receiving lactose-free formula tolerated it well. Data of subgroup analysis of rotavirus diarrhea revealed lactose-free formula scored higher than the control group for all parameters studied.