2 research outputs found
Susceptibility of Malassezia pachydermatis to azole antifungal agents evaluated by a new broth microdilution method
Malassezia pachydermatis   is considered an opportunistic pathogen of the outer ear duct in dogs and cats. This yeast can also be found in the skin, rectum, anal sacks and vagina. Eighty-two samples of this yeast isolated from dogs with the symptoms of external otitis from the Porto Alegre region were tested for their susceptibility to antifungal agents using the Broth Microdilution Method. The testing antifungal agents were Ketoconazole, Fluconazole and Itraconazole. Experimental essays determined that Sabouraud dextrose broth supplemented with 1% Tween 80 was the most appropriate medium for culture, for a ten-fold dilutions for the inocula, and 48 hours as the interval of readings. The ranges of the Minimal Inhibitory Concentrations (MICs) for the 82 samples were (a) Ketoconazole, from 0.015 to 0.25 mg/mL (mean of 0.08 mg/mL), (b) Fluconazole, from 1 to 32 mg/mL (mean of 9.22 mg/mL), and (c) Itraconazole, from 0.007 to 0.125 mg/mL (mean of 0.05 mg/mL). The isolates of M. pachydermatis showed an excellent level of susceptibility to antifungal azole agents, with all strains being susceptible to Itraconazole, and with only 2.4 % and 3.7% being resistant to Fluconazole and Kketoconazole, respectively. The use of the broth microdilution method allows the assessment of the susceptibility of large numbers of samples from M. pachydermatis isolates to the most common antifungal agents. The proposed procedure is easy to perform and considerably inexpensive compared with other existing tests, which makes this a method of choice for laboratorial use. A standardization of procedures currently used in veterinary mycology laboratories is required. Consistent results among laboratories could greatly benefit the establishment of proper comparisons between studies on antifungal susceptibility and therapeutic trials
DermatĂłfitos e leveduras isolados da pele de cĂŁes com dermatopatias diversas
As micoses cutĂąneas, causadas principalmente pelos dermatĂłfitos Microsporum spp. e Trichophyton mentagrophytes e pelas leveduras Malassezia pachydermatis e Candida albicans, sĂŁo as doenças fĂșngicas mais freqĂŒentes que acometem os cĂŁes. O principal objetivo deste estudo foi conhecer a ocorrĂȘncia desses fungos na pele de cĂŁes com dermatopatias de origens diversas. Uma população de 250 cĂŁes, com diferentes dermatoses, foi avaliada clinicamente no Serviço de Dermatologia do Hospital de ClĂnicas VeterinĂĄrias da Universidade Federal do Rio Grande do Sul, Porto Alegre - RS, no perĂodo de março de 2000 a março de 2001. Esses animais foram submetidos ao teste da lĂąmpada de Wood e obtiveram-se amostras de pĂȘlo e/ou escamas da pele para exame de microscopia direta e cultivo fĂșngico. Foram tambĂ©m realizados outros exames complementares, quando disponĂveis, no intuito de estabelecer o diagnĂłstico das diversas dermatopatias. As culturas fĂșngicas resultaram: 49,6% sem isolamento e 50,4% positivas, sendo isolados 29,6% fungos saprĂłbios e 20,8 % fungos causadores de micoses cutĂąneas (13,2 % Malassezia pachydermatis; 5,6% Microsporum canis e 2,0% Microsporum gypseum). As prevalĂȘncias das dermatopatias, distribuĂdas por grupos de doenças, foram as seguintes: 44,4% de origem imunopĂĄtica; 20% parasitĂĄria; 12,4% complexo seborrĂ©ia-disqueratinização; 11,2% bacteriana; 6,4% fĂșngica; 2,8% diversas, 2,0 % endĂłcrina e 0,4% congĂȘnita e hereditĂĄria