Two "Positive" Studies of Probiotics for Atopic Dermatitis

Question: In infants with established atopic dermatitis (AD) and suspected cow’s milk allergy, does administration of probiotics (Lactobacillus GG or a mixture of 4 probiotic strains) improve Scoring Atopic Dermatitis (SCORAD) index severity scores when compared with placebo at 4 weeks? Design: Randomized, controlled, double-blind, placebocontrolled study. Setting: Hospital skin and allergy center serving local health centers in Helsinki, Finland. Participants: Two hundred thirty infants, aged 1.4 to 11.9 months, with AD diagnosed by a physician and with symptoms suggestive of cow’s milk allergy. Intervention: Three groups were tested: the first (n=80) was given Lactobacillus rhamnosus GG at a dose of 5 10 colony-forming units; the second (n=76), a mixture of 4 probiotics strains; and the third, capsules containing inert matrix material (cellulose), each given twice daily with food for 4 weeks. In addition, all children and breastfeeding mothers avoided cow’s milk, and infants received extensively hydrolyzed whey formula milk. Additional treatment with emollients and 1% hydrocortisone was permitted. Measures: Change in severity as measured by the SCORAD index (range, 0-103) at the end of 4 weeks. Results: Mean changes in the SCORAD index from baseline to 4 weeks are shown in the Table and do not show any statistically or clinically significant differences among the 3 groups. No changes were noted among the 3 groups at 4 weeks after the treatment was stopped (ie, 8 weeks from baseline) or in the subgroup of those with evidence of true cow’s milk allergy as subsequently determined by double-blind, placebo-controlled food challenges. As part of an exploratory analysis, the authors highlight that there was a statistical difference between L rhamnosus GG and placebo in a subgroup of those who had AD and immunoglobulin E (IgE) sensitization for changes in the SCORAD index from baseline to 4 weeks after the treatment was stopped (mean change in the SCORAD index of −26.1 for L rhamnosus GG compared with −19.8 for placebo; P=.04), but not from baseline to 4 weeks. No differences between the probiotics mix and placebo were found in this subgroup. Authors’ Conclusion: Treatment with L rhamnosus GG may alleviate AD symptoms in IgE-sensitized infants but not in non–IgE-sensitized infants.