Efficacy of Probiotic Therapy on Atopic Dermatitis in Children: A Randomized, Double-blind, Placebo-controlled Trial

Purpose: To evaluate a therapeutic efficacy of probiotics mixture (probiotics) in the treatment of children with mild-to-moderate atopic dermatitis (AD). Methods: Randomized, double-blind, placebo-controlled, parallel trial with a washout period of 2 weeks and an intervention period for 6 weeks, conducted from November 2010 to October 2011. One hundred children with mild to moderate AD (2-9 years old) were randomly allocated to the probiotics (Lactobacilluss casei, Lactobacillus rhamnosus, Lactobacillus plantarum, and Bifidobacterium lactis) or placebo groups. The assessment of efficacy was based on the change in eczema area severity index (EASI), visual analogue scale for pruritus (VASP), fecal cell counts of each strains (log10[cell counts/g stool]), and serum cytokine levels (Interleukin-4 [IL-4]; IL-10; Tumor necrosis factor alpha, [TNF-alpha]) in weeks 0 and 6. Results: Demographics and baseline characteristics at the week 0 were not significantly different between the 2 groups. The significant increments in fecal-cell counts were observed in the probiotcs group at week 6 (P=0.00), while the cytokine levels between the 2 groups were not significantly different in week 6 (IL-4, P=0.50; IL-10, P=0.58; TNF-alpha, P=0.82). The probiotics significantly improved clinical severity after 6 weeks' intervention of probiotics; however, the placebo group also showed significant improvement (EASI; P=0.00, VASP; P=0.00). Conclusions: Our findings showed that probiotics successfully colonized in the intestine after 6 weeks' intervention; nevertheless, we could not find an additional therapeutic or immunomodulatory effects on the treatment of AD. Further long-term studies will be necessary to clarify the therapeutic efficacy of probiotics.