Epidemiological Analysis Of Three Kind Of Malassezia Disease In Kunming And In Vitro Activities Of Litsea Cubeba-oil Combined With Antifungal Drugs

Objective1. Investigate the distribution of Malassezia species in pityriasis vesicolor, Malassezia folliculitis and seborrheic dermatitis, predisposing factors and compared among the three diseases in Kunming, to provide the basis for the prevention of Malassezia infection and reduce the incidence of Malassezia diseases.2.To investigate antifungal susceptibility of Malassezia to Litsea cubeba-oil, and if the antifungal effect will be change when Litsea Cubeba-oil combined with ketoconazole, itraconazole and fluconazole respectively. So that to find a new efficient and low toxicity antifungal drug and provide a theoretical reference to Malassezia diseases.Method1.Cases collected from patients with pityriasis vesicolor, Malassezia folliculitis and seborrheic dermatitis (dandruff) who had clinical features and laboratory-confirmed infections,158cases were selected for surveying predisposing factors and training dander by using olive oil medium. All strains were analyzed by morphological and physiochemical features with standard strain;2.The M27-A programs promulgated by National Committee For Clinical Laboratory Standards, an antifungal drug susceptibility test in vitro had been conducted for the yeast forms of sixteen clinical Malassezia isolates with the Litsea cubeba-oil. We measured the minimum inhibitory concentration(MIC);3. At the same time we measured the MIC that the ketoconazole, itraconazole and fluconazole to the yeast forms of clinical isolates respectively and the Litsea Cubeba-oil combined with three antifungal drugs. We made a statistical analyse, and compared the MIC.Results1.We collected a total of158cases, males are104cases and females are54, the mean age is29.4, the proportion of patients with hyperhidrosis and oily skin are more than60%.111strains were isolated and6species were identified:38strains of M.furfur,29of M. sympodialis,20of M. pachydermatis,11of M. restricta,7of M. slooffiae.,6of M. obtusal;2. Eighty-seven clinical isolates of Malassezia(M.furfur、 M. sympodialis and M. pachydermatis)to Litsea cubeba-oil were all susceptible to Litsea cubeba oil, the MIC ranged from625ug/ml to20000ug/ml, the average of the MIC was3130.76±846.752μg/ml, there are differences in the mean MIC between the three Malassezia species,the mean MIC of M.furfur is significantly lower than the others.(p<0.05);3. There are some differences between the MIC range, MIC50and MIC90values of three kinds of azole antifungal agents against clinical isolates of Malassezia,the antifungal agents against the Malassezia from high sensitivity to low are: itraconazole, ketoconazole, fluconazole;4.Compared with the MIC of single agents and the Litsea Cubeba-oil combined with three antifungal drugs were conspicuously reduced.There was statistical significant difference (P<0.01),the average value of their FICIs were between0.5and1,combination has an additive effect.Conclusion1.Malassezia infections occur in young males, pityriasis vesicolor and Malassezia folliculitis are more likely to occur in patients with hyperhidrosis and oily skin. M.furfur, M. sympodialis and M. pachydermatis 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;2Antifungal susceptibility study proved that Litsea Cubeba-oil has antifungal effects on Malassezia spp;3. There are differences between three kinds of azole antifungal susceptibility in different species;4. The Litsea Cubeba-oil combined with three antifungal drugs could strengthen the antifungal effect of Malassezia.