PracticeUpdate Conference Series World Congress of Dermatology 2019

Role of Gut/ Cutaneous Dysbiosis in Dermatological Disease Highlighted More research is needed in this area.

I ntestinal and gut dysbiosis may play a far more substantial role in dermatologic conditions than previously recognized, according to a presenta- tion at WCD 2019. “In dermatology, there are two main fields of interest related to the study of the microbiota,” presenter Marco Pignatti, MD, from the University Clinic of Modena and Reggio Emilia in Italy, told Elsevier’s PracticeUpdate . “There are important functions of the gut microbiota in all chronic inflammatory diseases, like psoriasis, eczema, allergy, food allergy and autoimmune disease. And there is an important role for the skin microbiome in all pathologies in which a microbial agent is important in the pathogenesis, like acne, seborrheic dermatitis and rosacea. We have always considered them infectious diseases, but perhaps we should start to consider them as skin dysbiosis.” Currently, bacteria are considered to be the pri- mary pathogenic culprit in acne, fungi in seborrheic dermatitis, and protozoa in rosacea. All of the impli- cated microbes are also present in healthy skin, however. At present, these conditions are treated with antibiotic, antifungal and antiparasitic agents,

but “it might make more sense to create an equi- librium rather than kill one single component” of the cutaneous microbiome, suggested Dr. Pignatti. With regard to psoriasis, the gut microbiome is likely to play a more prominent role. He pointed out that there is a high degree of comorbidity between psoriasis and diseases of the gut, such as Crohn’s disease, and there is considerable overlap in the treatments for both. The gut microbiota comprises 10 times more cells than all our organs put together, he noted in his presentation. It weighs about 1.6 kg (about twice the weight of the heart and about 300 g more than the liver). It contains 3 to 8 million genes and has a level of metabolic activity equal to the liver. The key roles of the gut microbiota include maintain- ing the integrity of the intestinal wall, providing a defense against pathogens, eliminating toxins from the intestinal lumen, as well as modulating both immune and neuroendocrine function. Lack of diversity in the intestinal flora early in life has been linked with the development of allergies and asthma in childhood. “We know that the gut microbiota, skin microbi- ota, vaginal microbiota are all connected,” said Dr. Pignatti. “It is impossible to consider only one [in isolation]. We have to collect them together.” He pointed out how many skin diseases are exac- erbated by stress and explained that stress can influence gut health both directly and through life- style factors, including diet. This is a novel pathway through which dermatologists can consider the impact of stress on their patients’ skin. Some early clinical studies have linked gut health with skin disease and shown promising benefits of probiotics. In one study, 54% of acne patients showed evidence of alterations in intestinal flora.

Dr. Marco Pignatti

" We know that the gut microbiota, skin microbiota, vaginal microbiota are all connected. It is impossible to consider only one [in isolation]. We have to collect them together. "

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PRACTICEUPDATE CONFERENCE SERIES • WCD 2019