Laser and dermatosis: targeting Staphylococcus aureus

Laser treatment of atopic dermatitis could promote normalization of skin microbiota in lesions. Benefits include reduced wound severity and reduced skin dryness.

 

Atopic dermatitis (atopic eczema) is a chronic inflammatory skin condition, characterized by topical dryness, red lesions and outbreaks of itching. These changes to the skin barrier may be influenced by genetic and environmental factors, with possible implications for the skin microbiota. Previous studies have shown that the skin microbiota of subjects with atopic dermatitis is different from that of healthy skin. In particular, Staphylococcus aureus may colonize the damaged skin of patients and possibly contribute to worsen eczema flare-ups.

The effect of laser light on skin flora

One of the treatments for this type of dermatosis is laser light, especially 308 nm1 excimer laser. Although the efficacy of this laser light has been demonstrated, a question remains: does it affect the composition of the skin microbiota and its role in atopic dermatitis? A Japanese team is looking into this question by evaluating the development of microbial flora, lesions and skin barrier function of 11 patients following two months of weekly laser treatment.

Targeting Staphylococcus aureus

The primary post-treatment observation was reduced lesion severity, higher hydration index and improved skin barrier function. With respect to the skin microbiota, the researchers observed an increase of certain bacteria indicating improvement of skin hydration and, in particular, decreased abundance of harmful species of bacteria, i.e. Staphylococcus aureus. The laser treatment may therefore have a positive effect on the microbiota, especially by reducing the content of Staphylococcus aureus, which could result in an improvement of skin lesions in patients with atopic dermatitis.

 

1. Light emitted at the 308 nm wavelength is well-absorbed by skin tissue and organic compounds and enables removal of fine layers of damaged skin without affecting healthy areas.

 

Sources: 

Y. Kurosaki, M. Tsurumachi, Y. Kamata, et al. Effects of 308 nm excimer light treatment on the skin microbiome of atopic dermatitis patients. Photodermatology, Photoimmunology & Photomedicine, doi: 10.1111/phpp.12531.