The molecular detection for Malassezia furfur is used for the immediate, with high specificity and sensitivity laboratory diagnosis of the fungus (yeast) in various biological materials. Molecular testing for Malassezia furfur is included in the 14 different species of Yeast-like Fungi, Molecular Detection MycoScreen™.
Malassezia furfur is a commensal yeast of human skin that correlates with several common skin conditions.
Malassezia furfur is a member of a monophyletic genus of fungi normally found on human and animal skin. These lipid-dependent, commensal yeasts normally constitute greater than 80% of the total fungal population of human skin and are frequently isolated in both healthy and diseased hosts. Malassezia species have been implicated in several common dermatologic disorders, including seborrheic dermatitis, pityriasis versicolor, and Malassezia folliculitis. Recently, emerging evidence suggested Malassezia may contribute to other conditions such as atopic dermatitis and psoriasis. However, their exact pathogenic role remains a subject of controversy. Nevertheless, studies demonstrate that a reduction in the number of Malassezia with antifungal agents leads to the improvement of some skin conditions. In immunocompromised patients, Malassezia can act opportunistically, causing severe cutaneous and systemic infections.
M. furfur is unable to synthesize fatty acids independently and, therefore, depends on the oils produced in areas of the skin rich in sebaceous glands, especially the trunk, face, and scalp. Although it is a commensal microorganism that is a typical component present on the stratum corneum of human skin, infection results when the dimorphic yeast changes to its mycelial form.
M. furfur ubiquitously colonizes adults and even infants by age 3 to 6 months, and it does not have a predilection for any particular age or sex.
Seborrheic dermatitis affects 1 to 3% of the general population, and this rate would be even higher with the inclusion of milder cases of dandruff. Immunocompromised patients have the highest incidence of up to 33%. Seborrheic dermatitis has a seasonal pattern as it occurs more commonly in the winter months.
In pityriasis versicolor, adults aged 20 to 50 are most commonly affected when sebaceous gland activity is at its peak. Incidence is higher in the summer months and tropical areas, as prevalence approaches 40% in these regions. Pityriasis versicolor may also represent up to 3% of dermatology visits in temperate areas.
Malassezia folliculitis also more commonly occurs in hot and humid environments. It correlates with immunosuppression and often occurs concomitantly with acne and other Malassezia conditions, including seborrheic dermatitis and pityriasis versicolor.
Molecular diagnostic procedures allow rapid, accurate identification and quantification of Malassezia species. This has helped isolate M. furfur in deep-seated infections in immunocompromised patients and preterm infants in the neonatal intensive care unit who received lipid-laden nutrition via catheters.