In Vitro Antifungal Agents Susceptibility Of Malassezia Species Isolated From Pityriasis Versicolor、Malassezia Folliculitis And Seborrheic Dermatitis

Objective:Investigate the different of four antifungal agents susceptibility test in vitro of the same Malassezia Species isolated from three Malassezia associated diseases.Methods:1.The M27-A programs promulgatedby National Committee For Clinical Laboratory Standards, four antifungal drugs susceptibility test in vitro had been conducted for the yeast forms of 227 clinical mslasseziaisolates with ketoconazole、itraconazole、fluconazole and amphotericin B, measured the minimum inhibitory concentration(MIC) of the four antifungal drugs.2. We made a statistical analyse, and then we compared the MIC of M.furfur、M. sympodialis、M. pachydermatis and M. globose (isolated from Pityriasis versicolor、Malassezia folliculitis and seborrheic dermatitis).Results:1. We isolated a total of 244 Malassezia strains,77 of M.furfur,37 of M. sympodialis,28 of M. pachydermatis,85 of M. globosa,10 of M. restricta,7 of M. slooffiae; 2. We measured the MICs of ketoconazole、itraconazole、fluconazole and amphotericin B against M.furfur、M sympodialis、M. pachydermatis and M. globosa, their MIC ranges were 0.03-16mg/L,0.03-2,0mg/L,13-64 mg/L,0.03-8mg/L separatel y.3. Four kinds of antifungal agents against the Malassezia from high sensitivity to low are:itraconazole≥ketoconazole>amphotericin B> fluconazole.4.The susceptibility of ketoconazole against M. furfur which isolated from three different disease were statistically significant. The M.furfur isolated from Malassezia folliculitis was more sensitive than whivh from Pityriasis versicolor. And the M.furfur isolated from seborrheic dermatitis has lowest susceptibility of ketoconazole. In contrast, other Malassezia spceies has no diference to itraconazole、fluconazole and amphotericin B.Conclusion(s):1. M.furfur、M. sympodialis、M. pachydermatis and M. globosa, is the most common Malassezia species with in Kunming province, there are differences between the distribution of the dominant species and strains in each disease; The susceptibility of M.furfur, M. sympodialis, M. pachydermatis and M. globos is different.2. There are different between four kinds of antifungals susceptibility in different species.3. The susceptibility of ketoconazole against the M.furfur isolated from three different disease was statistically significant; 4. According to the test results, amphotericin B was not the best antifungal drugs to treat Malassezia accociated diseases, therefore we do not recommend use amphotericin B treat Malassezia deep infection. We find ketoconazole and itraconazole was better to treat Malassezia accociated diseases, but we do not recommend ketoconazole as a systemic treatment which can severly damage the liver. Therefore we recommend use itraconazole treat Malassezia deep infection.