title: In vitro susceptibility of isolates of Sporothrix schenckii to amphotericin B, itraconazole, and terbinafine: comparison of yeast and mycelial forms.
abstract: Forty-three clinical isolates of Sporothrix schenckii derived from humans and animals were evaluated in vitro for their susceptibility to amphotericin B, itraconazole, and terbinafine. MICs were determined by the method of micro dilution in liquid media, using protocols M27-A2 for the yeast form and M38-A for the mycelial form, both standardized by the Clinical Laboratory Standards Institute. In general, higher MICs were found for the mycelial form (intervals of up to two dilutions). In the case of amphotericin B, a significant difference in activity was observed, with higher values (p<0.05) found for the mycelial form. MICs for itraconazole and terbinafine were similar for both yeast and mycelial forms but slightly higher for mycelia. Although data presented here indicate different levels of susceptibility when both growth forms were compared, indicating an intrinsic difference between them, it is still difficult to draw a consensus as to which form correlates better with clinical findings. More studies are necessary to determine the criteria for in vitro tests that will lead to efficient therapeutic choices.
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil. lidikohler@hotmail.com
authors.forename: Lidiane Meire
authors.initials: LM
authors.lastname: Kohler
authors.forename: Betânia Maria
authors.initials: BM
authors.lastname: Soares
authors.forename: Daniel
authors.initials: D
authors.lastname: de Assis Santos
authors.forename: Maria Elisabete
authors.initials: ME
authors.lastname: Da Silva Barros
authors.forename: Júnia Soares
authors.initials: JS
authors.lastname: Hamdan
mesh_terms: D000666:Amphotericin B / Q000494:pharmacology*; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology; D002415:Cats; D004285:Dogs; D006736:Horses; D006801:Humans; D017964:Itraconazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D025282:Mycelium / Q000187:drug effects / Q000254:growth & development; D009281:Naphthalenes / Q000494:pharmacology*; D013175:Sporothrix / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification; D000077291:Terbinafine; D015003:Yeasts / Q000187:drug effects / Q000254:growth & development
chemical_list: D000935:Antifungal Agents; D009281:Naphthalenes; D017964:Itraconazole; D000666:Amphotericin B; D000077291:Terbinafine