Distribution of Malassezia species in pityriasis versicolor and seborrhoeic dermatitis in Greece. Typing of the major pityriasis versicolor isolate M. globosa.

ABSTRACT

BACKGROUND: The expansion of the genus Malassezia has generated interest in the epidemiological investigation of the distribution of new species in a range of dermatoses, on which variable results have been reported from different geographical regions. No data are thus far available from South-east Europe (Greece). OBJECTIVES: To study the distribution of Malassezia species in pityriasis versicolor (PV) and seborrhoeic dermatitis (SD) and to investigate whether polymorphisms in the internal transcribed spacer (ITS) 1 region facilitate detection of M. globosa and M. sympodialis subtypes. METHODS: In total, 109 patients with PV and SD and positive Malassezia cultures were included in the study. Age, gender, primary/recurrent episode, disease extent and clinical form of PV were recorded. ITS 1 polymorphisms of M. globosa and M. sympodialis type and clinical strains were investigated by polymerase chain reaction (PCR)-single-strand conformational polymorphism (SSCP) analysis. RESULTS: Malassezia globosa was the prevalent species isolated from PV and SD either alone (77% and 39%, respectively) or in combination (13% and 18%, respectively) with other Malassezia species. The pigmented form of PV was strongly correlated with the female gender. PCR-SSCP differentiated five subgroups of M. globosa with one being associated with extensive clinical disease. All M. sympodialis isolates displayed a homogeneous ITS 1 PCR-SSCP profile. CONCLUSIONS: Malassezia species isolation rates were in agreement with those reported from South-west Europe. PCR-SSCP of the ITS 1 is useful for highlighting prospective clinical implications of M. globosa subtypes.