FREQUENTLY ASKED QUESTIONS

 

I’ve never heard of Malassezia before, what are they? 
Malassezia are yeasts (aka fungi) which live both inside and on the surface of animals—including humans. They are best known as the cause of dandruff. Dandruff shampoos contain antifungal compounds which reduce Malassezia populations on the scalp, thus preventing dandruff. For example, Head and Shoulders contains the antifungal compound zinc pyrithione.

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How do Malassezia affect our health?
Until very recently, it was believed that Malassezia only lived on our skin. Therefore, they have only been thoroughly studied in dermatology. The first skin disease definitely attributed to Malassezia is tinea versicolor (aka Pityriasis versicolor—Gordon 1951). It is a mild disease which makes patches of skin either paler or darker. The second disease attributed to Malassezia is seborrheic dermatitis, which is considered to be a severe form of dandruff (Shuster 1984, Dawson 2007). Scientists are still debating Malassezia’s role in psoriasis, atopic dermatitis, acne and folliculitis (Ashbee 2002).

 

Malassezia were recently recognized as being often present in human internal organs. The only disease of internal organs for which Malassezia’s role has attained scientific consensus is acute infections of arteries in preterm infants fed with Intralipid (Shek 1989). Malassezia’s role in other diseases of internal organs needs to be investigated. This is the Malassezia Foundation’s main goal.

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Will antifungal drugs prevent or cure Malassezia diseases?
We hope so. Antifungal drugs are very effective in dandruff and seborrheic dermatitis. The efficacy of antifungal drugs for diseases of internal organs possibly caused by Malassezia is unknown. Small studies have suggested efficacy in Crohn’s disease (Samuel 2010), prostate cancer (Trachtenberg 1984, Antonarakis 2013), and in a pancreatic cancer mouse model (Aykut 2019). The Malassezia Foundation would like to definitely answer this question for important diseases using randomized clinical trials, as soon as enough evidence of Malassezia’s involvement becomes available.

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Can I catch Malassezia?
The consensus view is no: our skin is colonized from birth and for life (Nagata 2012), so you can’t catch them. However, we do not know how or when internal organs become colonized. Circumstantial evidence suggests sexual activity might be a risk factor for Malassezia colonization of certain internal organs (Laurence 2018). Epidemiological studies are urgently needed to answer these questions.

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My friend has a disease listed as possibly Malassezia-related, how can you help her?
The Malassezia Foundation does not intervene with patients directly—we fund basic and clinical research, in order to indirectly help your friend and millions of patients like her. If you think we should set up one or more research projects to advance basic or clinical knowledge related to your friend’s disease, please let us know.

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This question is more of a comment: you’ve missed a Malassezia-related disease!
It’s certainly possible. Please get in touch if you have evidence that Malassezia are involved in a disease which we have overlooked.

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How can I learn more about Malassezia?
Ashbee and Evans wrote a comprehensive and accessible short review about Malassezia in 2002 (Ashbee 2002). A panel of Malassezia experts wrote a textbook about Malassezia in 2010 (Malassezia and the Skin 2010). Malassezia’s presence in our internal organs was discovered in the interim, so these works are incomplete.