Changing of fecal flora and clinical effect of L. salivarius LS01 in adults with atopic dermatitis.

Goal: To evaluate cytokine stimulation with 3 strains of Lactobacillus salivarius in vitro and to assess changes in intestinal microflora and clinical improvements in adults with atopic dermatitis (AD) induced by the strain showing the best immunomodulatory features.

Background: AD is a common skin disease in children and adults. It is characterized by chronic inflammation, eczema, and increasing intestinal permeability. Various studies have shown that patients with AD presented some modifications in the intestinal microbiota composition; as a result, intestinal microflora is thought to have a pivotal role in this disease.

Methods: Thirty-eight patients aged from 18 to 46 years with moderate/severe AD were recruited. Subjects were randomized in a double-blind placebo-controlled study to receive active treatment with L. salivarius LS01: probiotic (n=19) or placebo (n=19). Cytokine production was determined by means of specific quantitative enzyme-linked immunosorbent assays. Intestinal bacterial groups were quantified using conventional culture techniques, whereas L. salivarius LS01 was identified using polymerase chain reaction and pulse field gel electrophoresis.

Results: L. salivarius LS01 showed the best immunomodulatory features and it was chosen for the second phase of the study. AD subjects showed a reduction in their SCORAD score after probiotic treatment and a significant decrease in the staphylococci load compared with the placebo group. Moreover, L. salivarius LS01 showed the ability to reduce the production of Th2 cytokines, maintaining the production of Th1 cytokines stable.

Conclusions: Treatment with the L. salivarius LS01 strain seems to positively modify clinical and immunologic status and dermatology life quality in a group of adults affected by moderate/severe AD, leading to a rebalancing of altered intestinal microbiota.