Malassezia beyond tinea versicolor: the newest wolf in sheep's clothing pathogen?

Malassezia (M) yeasts are lipophilic commensals and part of the healthy human skin flora, although they may play a role as opportunistic cutaneous pathogens, being a wellknown cause of pityriasis versicolor (PV), the prototypical Malassezia-associated skin infection. Recent data has shown new pathogenic potential of Malassezia which under insufficiently understood conditions may be implicated in exacerbations of inflammatory dermatoses, especially on a clinical variant of atopic dermatitis (AD) and some other dermatological and systemic diseases previously unrelated to this yeast. Although there is no evidence that Malassezia species invade the skin, there actually is evidence that their antigens might penetrate a previously damaged epidermis and interact with cells that take part in the skin's immune system, thus inducing the production of a variety of cytokines which may trigger flares of certain dermatoses. The purpose of this article is to discuss clinical cases reflecting the spectrum of pathogenic interactions of Malassezia fungus with human skin. [ABSTRACT FROM AUTHOR]