Probiotics and atopic dermatitis. A new strategy in atopic dermatitis.

Over the last few decades, the prevalence of atopic dermatitis has been increasing from 2% to 100%, with 90% of cases within 5 years of age versus 6% between 6 and 10 years and 2% after 10 years, and environmental factors may possibly play an important role in this increase as in other atopic diseases. Many findings suggest an important role of atopy in atopic dermatitis; moreover, 40% of children with atopic dermatitis have food allergy and the removal of the food allergen from the patient's diet leads to a significant clinical improvement. In a possible scenario, IgE-bearing dendritic cells are likely to process allergens acquired in the gastrointestinal tract, circulate to the skin and activate local T cells. Cultures of beneficial live microorganisms characteristic of the commensal microflora are administered with probiotic functional foods in order to provide a microbial challenge for the maturation of gut-associated lymphoid tissue, which the infant often lacks. The probiotic effects are attributed to normalisation of the increased intestinal permeability and balancing gut microecology, improvement of the immunological defence barrier (IgA) of the intestine, alleviation of the intestinal inflammatory response, and downregulation of proinflammatory cytokines characteristic of local and systemic allergic inflammation.