Isolation and identification of Malassezia species from patients of pityriasis versicolor and its comparison with normal subjects

Dr Vaibhav Misra; Dr Abhishek Kumar Jain

Volume : VII, Issue : IX, September - 2017

Isolation and identification of Malassezia species from patients of pityriasis versicolor and its comparison with normal subjects

Dr Vaibhav Misra, Dr Abhishek Kumar Jain

Abstract :

Background: Pityriasis versicolor is a superficial infection of the stratum corneum, caused by a group of yeasts formerly named pityrosporium. The taxonomy of these lipophilic yeasts has recently been modified and includes seven species referred as Malassezia.

Aims: The aim of this study is to compare the distribution of Malassezia species isolated from pityriasis versicolor lesions and those isolated from healthy skins.

Methods: This cross sectional epidemiological case–control study was carried out at LTMG Hospital, Mumbai. 116 clinically diagnosed patients of pityriasis versicolor and 50 healthy persons of all age group and both sexes were studied. Skin scrapping was inoculated on Leeming and Notman agar, followed by subculture on Sabouraud’s dextrose agar with chloramphenicol and gentamicin with olive oil overlay as well as without olive oil. Biochemical tests and Tween assimilation test were performed. 10 per cent KOH mount and Grocott‘s Methenamine Silver (GMS) staining was also done. Statistical analysis was done using chi–square test.

Results: Out of the total 116 case, 104 were mycologically proved (direct examination or culture or both positive) only 38 were culture positive. Four species of Malassezia were isolated mainly from 38 culture positive cases. M. sympodialis 52.6 per cent (n=20), M. globosa 15.9 per cent (n=6), M. slooffiae 7.9 per cent (n=3) and M. furfur 2.6 per cent (n=1). All 50 healthy people were negative for fungus.

Conclusion: Although pityriasis versicolor has worldwide occurrence, its frequency is variable and depends on different climatic, occupational and socio–economic conditions. Both sexes and all age group are equally affected with slight predisposition to males. In our study most common species of Malassezia isolated was M. sympodialis (52.6 per cent).