Understanding Atopic Dermatitis

Atopic dermatitis (AD), also known as atopic eczema, is a common chronic inflammatory skin condition that is characterised by inflamed, dry and itchy skin. Multiple factors contribute to AD such as genetics and environment, although the exact mechanism is not well understood. Treatment is often very difficult, involving the use of topical steroids or oral antibiotics which can cause adverse side effects. Studies have shown that individuals with AD have a disturbed skin microbiome and are more often colonised with Staphylococcus aureus compared to healthy individuals.

A summary of what we know:

• S. aureus contributes to skin barrier defects and inflammation in AD (Totté et al., 2016)

• Recent research has reported that commensal bacteria residing on normal skin (S. hominis) produce antimicrobial peptides that exhibit activity against S. aureus (Nakatsuji et al., 2017)

• Topical application of S. hominis has been shown to improve skin condition and may improve various skin conditions such as AD (Ohshima, Kurosumi and Kanto, 2021)

Current solutions:

Clinical data suggests a probiotic product containing Lactobacillus reuteri DSM 17938 could be a promising topical product for the management of AD (Butler, Christoffer and Axelsson, 2020).

References

Butler É, Lundqvist C, Axelsson J. Lactobacillus reuteri DSM 17938 as a Novel Topical Cosmetic Ingredient: A Proof of Concept Clinical Study in Adults with Atopic Dermatitis. Microorganisms. 2020 Jul 11;8(7):1026. doi: 10.3390/microorganisms8071026. PMID: 32664536; PMCID: PMC7409218.

Ohshima H, Kurosumi M, Kanto H. New solution of beauty problem by Staphylococcus hominis: Relevance between skin microbiome and skin condition in healthy subject. Skin Res Technol. 2021 Sep;27(5):692-700. doi: 10.1111/srt.13001. Epub 2021 Jan 28. PMID: 33511688.

Nakatsuji T, Chen TH, Narala S, Chun KA, Two AM, Yun T, Shafiq F, Kotol PF, Bouslimani A, Melnik AV, Latif H, Kim JN, Lockhart A, Artis K, David G, Taylor P, Streib J, Dorrestein PC, Grier A, Gill SR, Zengler K, Hata TR, Leung DY, Gallo RL. Antimicrobials from human skin commensal bacteria protect against Staphylococcus aureus and are deficient in atopic dermatitis. Sci Transl Med. 2017 Feb 22;9(378):eaah4680. doi: 10.1126/scitranslmed.aah4680. PMID: 28228596; PMCID: PMC5600545.

Totté JE, van der Feltz WT, Hennekam M, van Belkum A, van Zuuren EJ, Pasmans SG. Prevalence and odds of Staphylococcus aureus carriage in atopic dermatitis: a systematic review and meta-analysis. Br J Dermatol. 2016 Oct;175(4):687-95. doi: 10.1111/bjd.14566. Epub 2016 Jul 5. PMID: 26994362.