Distribución de las especies de Malassezia en pacientes con pitiriasis versicolor y en individuos sanos

Abstract

Purpose This study analyses the prevalence of Malassezia species in the skin lesions of patients with pityriasis versicolor and in the healthy skin of a healthy individual group. Materials and Methods The group studied included one hundred and fifty patients with pityriasis versicolor. Samples were taken from the pityriasis versicolor lesions by means of Sellotape for direct microscopy with KOH + Parker ink, and scales were obtained by scarping for culture, and inoculated on modified Dixon agar plates. Samples were also taken of healthy skin of the forehead and of the shoulders of one hundred and fifty healthy individual group. All these samples were used for culture and inoculated on the medium, but were not examined by direct microscopy. The yeasts were identified by their morphological and physiological characteristics. Results M. globosa was isolated in 130 cases (86,7%) of 150 patients with pityriasis versicolor. M. sympodialis was also found in 63 cases (42%). In healthy skin of the forehead of healthy individuals a total of 23 isolates from the 150 samples were obtained. M. sympodialis was the predominant species (56,52%), followed by M. globosa (47,8%). In healthy skin of the shoulders a total of 91 isolates were obtained. M. sympodialis was by far the predominant species (91,2%) followed by M. globosa (7,6%) and M. slooffiae (1,09%). Conclusions M. globosa, in its mycelial phase, is the predominant species in the ethiology of pityriasis versicolor.