Distribution of Malassezia species on the skin of patients with psoriasis.

INTRODUCTION

Malassezia species can induce the expression of interleukin-17 (IL-17), which plays an important role in the inflammatory and immune response in psoriasis (PS). The purpose of this study was to investigate the Malassezia species composition in patients with PS and healthy individuals and explore the role of Malassezia species in the pathogenesis of PS.

MATERIALS AND

METHODS

A total of 28 patients with PS and 10 age- and sex-matched healthy individuals participated in this study. Specimens collected from the lesional and non-lesional skin of patients with PS and the skin of healthy individuals were analyzed by using nested PCR.

RESULTS

The relative abundance of Malassezia species was 84.96% in healthy subjects, more than twice that in patients with PS (P<0.01). M. restricta (43.09%) and M. globosa (41.38%) were the main Malassezia species in patients with PS followed by M. furfur (4.84%) and M. sympodialis (2.49%). M. sympodialis accounted for 18. 81% of the Malassezia species in healthy subjects, which was nearly eight times higher than in patients with PS (P<0.01). Further, M. furfur was detected both on lesional and non-lesional psoriatic skin, but it was not found on the skin of healthy individuals.

CONCLUSIONS

The Malassezia species composition in patients with PS differed from that of healthy individuals. M. restricta and M. globosa were the main Malassezia species in patients with PS.