Frequency, Distribution and Genotyping of Malassezia Species in Patients with Psoriasis vulgaris

Abstract Background: Malassezia species are reported to play a role in the etiology of Psoriasis vulgaris. Objective: The aim of this study was to determine the presence, frequency, distribution, and genotyping of skin colonization of Malassezia species in Psoriasis vulgaris and to compare with healthy individuals and to investigate its relationship with the severity of the disease. Methods: Skin samples were taken from scalp, arm, body, and leg of 34 psoriasis patients (lesional/non-lesional skin) and 30 healthy volunteers. Overall, 392 skin scraping samples were taken for the isolation of Malassezia species, which were incubated on the modified-Dixon agar. Conventional culture methods were used for Malassezia species identification. In isolates, genotyping was carried out by PCR-RFLP method. Results: In the samples from psoriatic lesions, most frequently isolated Malassezia species were M.globosa and M.furfur. Similarly, the most frequently isolated species in healthy volunteers was M. globosa; followed by M.restricta and M.sympodialis. The M.furfur isolation rate in psoriatic scalp and leg lesions of the patients was significantly higher than in healthy volunteers. There was no relationship between the severity of the disease and the isolated species. Conclusion: It was found that there was a difference between patients with psoriasis and healthy controls regarding presence and frequency of Malassezia species. Therefore, our study results support the view that Malessezia species may be associated with the etiopathogenesis of psoriasis. In addition, we surmise that the treatment applications for the regulation of skin microbiota of psoriasis patients will contribute positively to the treatment of psoriasis.