Analysis of the skin mycobiome in adult patients with atopic dermatitis.

With the recent availability of culture-independent sequencing methods, studies have been conducted to analyse skin micro-organisms present in patients with atopic dermatitis (AD). However, the database on the skin fungal communities, "mycobiome," has been relatively restrictive compared with the bacterial world. We aimed to comparatively analyse the overall skin mycobiome between patients with AD and healthy individuals in the Korean population. We analysed skin swab samples obtained from the antecubital fossae of 8 patients with AD and 8 healthy controls. Using sequencing method followed by direct DNA extraction and molecular PCR, taxonomic compositions of fungi at stepwise level ranks were analysed. The phylogenic marker used was internal transcribed spacer 2 regions of DNA. We observed the tendency of higher intra- and interpersonal taxonomic diversity at genus and species levels in AD samples. Non-Malassezia fungal diversity was also noticeable in the patient group compared with healthy controls. Malassezia globosa and Malassezia restricta were prevalent in all samples across both study groups, and some Malassezia species, including Malassezia sloofiae and Malassezia dermatis, characterized AD. Our data might provide a new insight into the mycobiome of adult AD, which contributes to building a systemic mycobiome database in AD.