title: Azole resistance in Candida spp. isolated from Catú Lake, Ceará, Brazil: an efflux-pump-mediated mechanism.
abstract: Since, there is no study reporting the mechanism of azole resistance among yeasts isolated from aquatic environments; the present study aims to investigate the occurrence of antifungal resistance among yeasts isolated from an aquatic environment, and assess the efflux-pump activity of the azole-resistant strains to better understand the mechanism of resistance for this group of drugs. For this purpose, monthly water and sediment samples were collected from Catú Lake, Ceará, Brazil, from March 2011 to February 2012. The obtained yeasts were identified based on morphological and biochemical characteristics. Of the 46 isolates, 37 were Candida spp., 4 were Trichosporon asahii, 3 were Cryptococcus laurentii, 1 Rhodotorula mucilaginosa, and 1 was Kodamaea ohmeri. These isolates were subjected to broth microdilution assay with amphotericin B, itraconazole, and fluconazole, according to the methodology standardized by the Clinical and Laboratory Standards Institute (CLSI). The minimum inhibitory concentrations (MICs) of amphotericin B, itraconazole, and fluconazole were 0.03125-2μg/mL, 0.0625 to ≥16μg/mL, and 0.5 to ≥64μg/mL, respectively, and 13 resistant azole-resistant Candida isolates were detected. A reduction in the azole MICs leading to the phenotypical reversal of the azole resistance was observed upon addition of efflux-pump inhibitors. These findings suggest that the azole resistance among environmental Candida spp. is most likely associated with the overexpression of efflux-pumps.
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil. Electronic address: brilhante@ufc.br.
authors.forename: Raimunda S N
authors.initials: RS
authors.lastname: Brilhante
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil; School of Veterinary Medicine, Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Manoel A N
authors.initials: MA
authors.lastname: Paiva
authors.affiliation: School of Veterinary Medicine, Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Célia M S
authors.initials: CM
authors.lastname: Sampaio
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Débora S C M
authors.initials: DS
authors.lastname: Castelo-Branco
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Carlos E C
authors.initials: CE
authors.lastname: Teixeira
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil; School of Veterinary Medicine, Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Lucas P
authors.initials: LP
authors.lastname: de Alencar
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil; School of Medicine, Christus College - UNICHRISTUS, Fortaleza, Ceará, Brazil.
authors.forename: Tereza J P G
authors.initials: TJ
authors.lastname: Bandeira
authors.affiliation: Department of Statistics and Applied Mathematics, Federal University of Ceará, Fortaleza, CE, Brazil.
authors.forename: André J
authors.initials: AJ
authors.lastname: Monteiro
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Rossana A
authors.initials: RA
authors.lastname: Cordeiro
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Waldemiro A
authors.initials: WA
authors.lastname: Pereira-Neto
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: José J C
authors.initials: JJ
authors.lastname: Sidrim
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: José L B
authors.initials: JL
authors.lastname: Moreira
authors.affiliation: Department of Pathology and Legal Medicine, Faculty of Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil; School of Veterinary Medicine, Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Marcos F G
authors.initials: MF
authors.lastname: Rocha
mesh_terms: D000935:Antifungal Agents / Q000378:metabolism*; D001393:Azoles / Q000378:metabolism*; D001693:Biological Transport, Active; D001938:Brazil; D002175:Candida / Q000187:drug effects* / Q000302:isolation & purification*; D025141:Drug Resistance, Fungal; D060106:Lakes / Q000382:microbiology*; D008826:Microbial Sensitivity Tests
chemical_list: D000935:Antifungal Agents; D001393:Azoles
keywords: Antifungal resistance; Aquatic environments; Candida spp.; Yeast microbiota