Probiotic Lactobacillus Rhamnosus GG for Pediatric Atopic Dermatitis

Overview

Atopic dermatitis (AD) is a multifactorial, chronic inflammatory skin disorder that results in areas of dry, itchy skin. AD affects up to 20% of children in Western societies and represents a prevalent, burdensome, and psychologically important pediatric concern. It often appears in infancy and may persist into adolescence and adulthood. This complex disease is typified by defective skin barrier function with activation of abnormal immunological and inflammatory pathways upon exposure to ubiquitous environmental allergens. It often appears in infancy and may persist into adolescence and adulthood. This complex disease is typified by defective skin barrier function with activation of abnormal immunological and inflammatory pathways upon exposure to ubiquitous environmental allergens. This complex disease is typified by defective skin barrier function with activation of abnormal immunological and inflammatory pathways upon exposure to ubiquitous environmental allergens. This phenomenon may be primarily related to mutations in important barrier proteins, in the same fashion as filaggrin in the atopic skin, or may be secondary, reflecting the intestinal mucosal damage caused by local hypersensitivity reactions to food antigens or to microbial components as in inflammatory bowel disease. Conventional therapy for AD consists of elimination of exacerbating factors, moisturizers to maintain skin hydration, antihistamines to alleviate pruritus, topically applied corticosteroids, or topical calcineurin inhibitors to control inflammation. Severe forms of atopic dermatitis may need systemic corticosteroids, oral cyclosporine, and/or phototherapy. Probiotics have been suggested as a novel treatment approach for atopic dermatitis. Specific probiotics have been shown to normalize intestinal permeability, to counteract intestinal immune dysfunction and to normalize gut dysbiosis. Hence, their clinical benefit may reside in the control of gut inflammation induced by various intraluminal antigens and enhancement of adaptive and especially innate immune responses. Indeed, above and beyond balancing the gut microecology and promoting host immune defences, specific probiotics might further aid in controlling the microbial colonization of the skin, thereby reducing proneness to secondary infections which typically cause sustained symptoms. However, there are conflicting evidence on the utility of selected probiotic strains for atopic dermatitis, and major problems are due to dose and viability of strain used, duration of treatment, study population. The aim of this randomized, double-blind, placebo-controlled study is to evaluate the efficacy of the most studied probiotic in the pediatric allergy field - Lactobacillus rhamnosus GG (LGG) - in children affected by atopic dermatitis.