There seems to be a complex interaction between the cutaneous immune system and the microbiota which plays a role in the appearance of atopic eczema. Its modulation with probiotics is a promising avenue as a preventive measure.
Atopic eczema, more commonly called atopic dermatitis, can affect up to 25% of children and 7% of adults in industrialized countries. This allergic affliction manifests itself in the form of dryness and cutaneous lesions, progressing by flares: redness, itching, blisters, and scabs1.
Genetic and environmental factors
Dermatitis is related to a genetic predisposition that causes structural anomalies in the skin, as well as immune system hyperreactivity. Between 50% and 70% of patients who suffer from atopic dermatitis have a first-degree relative with the disease. Environmental factors are also suspected of changing the balance in the immune system1.
Gastrointestinal microbiota associated with atopy
The intestinal and cutaneous microbiota seem to contribute to the affliction, although the mechanisms are not clearly established. Several studies have shown a link between the intestinal microbiota and the allergy2, with changes in the former, for example, before the appearance of an atopic syndrome3. Dysbioses are also present in the cutaneous microbiota4. There are likely connections between the intestinal and cutaneous microbiota through the passage of bacteria from one tissue to another, or through interrelationships with other organs like the immune system and the brain5,6,7,8.
Probiotics are extremely promising
Standard treatment of atopic dermatitis flares is based on the use of topical steroids, or topical immunomodulators for the most severe cases. Phototherapy has also been proven effective.
Current research is directed towards correcting dysbioses as a preventive measure. The neonatal period seems particularly opportune to induce effective immunomodulation and reduce the risk of atopic eczema. A meta-analysis showed that the administration of probiotics like Lactobacillus rhamnosus GG to pregnant women seems promising to prevent atopic dermatitis in children9. Furthermore, several studies have shown the usefulness of Lactobacillus salivarius in treating atopic dermatitis in adults and children10,11.
1. Société française de dermatologie, http://dermato-info.fr/article/La_dermatite_atopique
2. Candela M, Rampelli S, Turroni S, et al. Unbalance of intestinal microbiota in atopic children. BMC Microbiol 2012 ; 12 : 95.
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10. Drago L. et al. Effects of Lactobacillus salivarius LS01 (DSM 22775) treatment on adult atopic dermatitis: a randomized placebocontrolled study. Int J Immunopathol Pharmacol. 2011;24:1037-48.
11. Niccoli AA. et al. Preliminary results on clinical effects of probiotic Lactobacillus salivarius LS01 in children affected by atopic dermatitis. J Clin Gastroenterol. 2014;48 Suppl 1:S34-6.