Recent research indicated that disturbances in gut microbiota composition may significantly contribute to the pathogenesis of atopic dermatitis.

Atopic dermatitis is a chronic, inflammatory skin condition marked by severe pruritus and xerosis, affecting 15% to 30% of children and 10% of adults worldwide. The increasing prevalence of atopic dermatitis imposes significant financial and psychological burdens on patients, who may also experience severe mental disorders such as anxiety, depression, and suicidal tendencies. In 2019, there were an estimated 390 million patients with atopic dermatitis globally. Current projections indicate that this number could rise to 450 million by 2024 and 520 million by 2030, with over 33.3% of cases being moderate to severe.

The gut microbiota, a complex community of microorganisms in the human intestine, play a pivotal role in immune regulation and skin health. The gut microbiota population is approximately 100 times larger than the human genome, with over 99% consisting of Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria. Evidence suggested that alterations in gut microbiota composition can lead to dysregulated immune responses, contributing to the pathogenesis of atopic dermatitis. Patients with atopic dermatitis often exhibit decreased diversity and stability in their gut microbiota.

In the study, published in Clinical, Cosmetic and Investigational Dermatology, investigators reviewed current literature on the role of gut microbiota in atopic dermatitis. They found that the diversity of gut microbiota is generally lower in patients with atopic dermatitis compared with healthy individuals. Specific bacteria, including Bifidobacterium and Lactobacillus, are often depleted in atopic dermatitis, while pathogenic bacteria like Clostridium difficile and Staphylococcus aureus are more abundant.

Probiotics such as Lactobacillus and Bifidobacterium have shown efficacy in reducing atopic dermatitis severity by enhancing gut microbiota diversity and modulating immune responses. Fecal microbiota transplantation is another approach, wherein healthy gut bacteria are transplanted into patients with atopic dermatitis. 

The authors reported no potential conflict of interest.