IDENTIFICATION OF MALASSEZIA SPECIES - A PRACTICAL APPROACH

Background and objective. The genus Malassezia has recently been enlar ged to include seven distinct species. Our purpose was to present a pr actical approach to the identification of all Malassezia yeasts from c linical material. Materials and methods. Representative isolates corre sponding to the seven Malassezia species were examined. Yeast cell mor phology was described. Ability to utilize individual Tweens (20, 40, 6 0 and 80) was assessed by the technique of diffusion. Catalase reactio n was also determined. Results and discussion. All Malassezia species, except M. furfur, were proved to have stable morphological characteri stics. Bottle-shaped yeasts might be globose (M. globosa, sometimes M. furfur), ovoid (M. pachydermatis, M. sympodialis, M. restricta, M. sl ooffiae, M. furfur) or cylindrical (M. obtusa, M. furfur). M. pachyder matis was confirmed to be non-lipid-dependent and could therefore be g rown on conventional media. M. restricta was the only lipid-dependent species to lack catalase. Species were further distinguished by the fo ur Tween assimilation patterns. Conclusion. The methods described in t his study do not require elaborate equipment and yet represent a satis factory identification scheme for Malassezia species.