title: In vitro susceptibility of environmental isolates of Exophiala dermatitidis to five antifungal drugs.
abstract: Several dematiaceous fungi frequently isolated from nature are involved in cases of superficial lesions to lethal cerebral infections. Antifungal susceptibility data on environmental and clinical isolates are still sparse despite the advances in testing methods. The objective of this study was to examine the activities of 5-flucytosine, amphotericin B, itraconazole, voriconazole and terbinafine against environmental isolates of Exophiala strains by minimum inhibition concentration (MIC) determination. The strains were obtained from hydrocarbon-contaminated soil, ant cuticle and fungal pellets from the infrabuccal pocket of attine gynes. Broth microdilution assay using M38-A2 reference methodology for the five antifungal drugs and DNA sequencing for fungal identification were applied. Terbinafine was the most active drug against the tested strains. It was observed that amphotericin B was less effective, notably against Exophiala spinifera, also studied. High MICs of 5-flucytosine against Exophiala dermatitidis occurred. This finding highlights the relevance of studies on the antifungal resistance of these potential opportunistic species. Our results also contribute to a future improvement of the standard methods to access the drug efficacy currently applied to black fungi.
authors.affiliation: Center for Study of Social Insects, IB, UNESP- São Paulo State University, Rio Claro, SP, Brazil.
authors.forename: Ana Paula Miranda
authors.initials: AP
authors.lastname: Duarte
authors.forename: Fernando Carlos
authors.initials: FC
authors.lastname: Pagnocca
authors.forename: Noemi Carla
authors.initials: NC
authors.lastname: Baron
authors.forename: Marcia de Souza Carvalho
authors.initials: Mde S
authors.lastname: Melhem
authors.forename: Gislene Aparecida
authors.initials: GA
authors.lastname: Palmeira
authors.forename: Dejanira de Franceschi
authors.initials: Dde F
authors.lastname: de Angelis
authors.forename: Derlene
authors.initials: D
authors.lastname: Attili-Angelis
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D004783:Environmental Microbiology; D005093:Exophiala / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008826:Microbial Sensitivity Tests; D017422:Sequence Analysis, DNA
chemical_list: D000935:Antifungal Agents; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer