Malassezia species in healthy skin and in dermatological conditions

Abstract

The genus Malassezia comprises lipophilic species, the natural habitat of which is the skin of humans and other warm-blooded animals. However, these species have been associated with a diversity of dermatological disorders and even systemic infections. Pityriasis versicolor is the only cutaneous disease etiologically connected to Malassezia yeasts. In the other dermatoses, such as Malassezia folliculitis, seborrheic dermatitis, atopic dermatitis, and psoriasis, these yeasts have been suggested to play pathogenic roles either as direct agents of infection or as trigger factors because there is no evidence that the organisms invade the skin. Malassezia yeasts have been classified into at least 14 species, of which eight have been isolated from human skin, including Malassezia furfur, Malassezia pachydermatis, Malassezia sympodialis, Malassezia slooffiae, Malassezia globosa, Malassezia obtusa, Malassezia restricta, Malassezia dermatis, Malassezia japonica, and Malassezia yamatoensis. Distributions of Malassezia species in the healthy body and in skin diseases have been investigated using culture-based and molecular techniques, and variable results have been reported from different geographical regions. This article reviews and discusses the latest available data on the pathogenicity of Malassezia spp., their distributions in dermatological conditions and in healthy skin, discrepancies in the two methods of identification, and the susceptibility of Malassezia spp. to antifungals.

Commensal Fungi in Health and Disease

“…Pityriasis versicolor is the only common skin disease that is directly and unequivocally attributable to Malassezia . It is characterized by skin invasion of the hyphal form of Malassezia and can be caused by a variety of species including M. globosa, M. sympodialis , and M. furfur (Prohic et al, 2016). Malassezia has also been implicated in the pathogenesis of a variety of other immune mediated skin disorders such as seborrheic dermatitis, atopic dermatitis and psoriasis.…”

Pathogenic yeasts recovered from acne vulgaris: Molecular characterization and antifungal susceptibility pattern

“…in skin as microflora in comparison to Candida , a quick look at the results of the above-mentioned studies can get us to the conclusion that Candida , a normal flora of the skin, can also be considered as a factor in acne. [22] With the exception of Cp1 and Cp8 isolates which were relatively resistant, other species of the Candida and other isolates of C. parapsilosis were sensitive to KTZ, FCZ, and ITZ.…”

A Dysbiotic Mycobiome Dominated by <em>Candida albicans</em> is Identified within Oral Squamous Cell Carcinomas

“…Malassezia spp are normal colonizers of healthy skin [37] and have been recently found to be dominant members of the salivary mycobiome [14]. Aspergillus, Alternaria, and Cladosporium have also been described as core oral fungal taxa [13,14].…”