Molecular Analysis Of Malassezia Species Of The Scales Of Pityriasis Versicolor Patients

Pityriasis versicolor (PV) is a common superficial fungal infection of the skin. It is caused by Malassezia spp. , which is the normal human saprophyte. Under certain conditions, both exogenous and endogenous, the fungus can convert from a yeast to a pathogenic mycelial form. Since the taxonomy of Malassezia spp. has recently been modified to include 7 species, there are several reports on the species from the PV scales, but the results are different.Objective: This study was aimed at the development of nested polymerase chain reaction (PCR) procedure directly applicable to pityriasis versicolor skin scales and at the assessment of its value in rapid laboratoryconfirmation and identification of each of the seven Malassezia species.Methods: Malassezia DNA was extracted from PV skin scales and amplified by nested PCR using the internal transcribed spacer region of the rRNA gene primers for amplification of the Malassezia DNA sequences.Results: 105 skin-scale isolates were tested and identified 5 kinds 311 strains. And multiple Malassezia species were detected in the same specimen. The detected frequencies are: M. globosa 80.0%, M. restrieta 81. 9%, M. sympodialis 11. 1%, M. furfur 41. 9%, M. obtusel5. 2%. No M. pachydermatis or M. slooffia. is detected.Conclusion: There are several kinds of Malassezia in the scales of PV patients and the M. globosa, M. restricta, M. sympodialis, M. furfur are the dominant strains.