Gut microbiome response to a probiotic product in subjects with atopic dermatitis

Atopic dermatitis is a chronic recurrent inflammatory skin disease with a high impact on the comfort of those who are affected, and long-term treated with corticosteroids with limited efficacy and a high prevalence of side-effects. Because of the side effects of these treatments, new strategies for recovery from AD wounds are continually being explored. A recent clinical trial with the probiotics Bifidobacterium animalis subsp. lactis CECT 8145, Bifidobacterium longum CECT 7347 and Lactobacillus casei CECT 9104 achieved a significant improvement in SCORAD (Scoring Atopic Dermatitis) index in children (4-17 years) with AD (clinicaltrials.gov Identifier: NCT02585986). Diversity (Shannon and Simpson indexes) did not significantly change after probiotic consumption. In probiotic group, genera Bacteroides, Ruminococcus and Bifidobacterium significantly increased their levels while Faecalibacterium decreased, compared to placebo. Faecalibacterium showed the highest presence and significant positive correlation with AD severity-microbiome whereas Abyssivirga, Lactococcus and Bifidobacterium were inversely correlated with AD severity. The results indicate that the consumption of the probiotic here assayed modulate the gut microbiome with significant changes in genera Faecalibacterium and Bacteroides. In turn, the improvement in SCORAD correlates with a decrease in Faecalibacterium and an increase in Bifidobacterium, among others.