title: Biofilm Production and Antibiofilm Activity of Echinocandins and Liposomal Amphotericin B in Echinocandin-Resistant Yeast Species.
abstract: The echinocandins and liposomal amphotericin B are active against biofilm produced by echinocandin-susceptible Candida strains. However, few data have been reported on the production of biofilm by echinocandin-resistant isolates and their antifungal susceptibility. We studied the production of biofilm by fks mutant Candida strains and intrinsically echinocandin-resistant non-Candida isolates and the susceptibility of both entities to liposomal amphotericin B and echinocandins. We analyzed the production of biofilm by isolates from patients with fungemia (fks mutant Candida, n = 5; intrinsically echinocandin-resistant non-Candida, n = 12; and Candida wild type, n = 10). Biofilm formation was measured to classify strains according to biomass (crystal violet assay) and metabolic activity (XTT reduction assay). Preformed biofilms were tested against liposomal amphotericin B, caspofungin, micafungin, and anidulafungin. The sessile MIC was defined as the antifungal concentration yielding a 50% or 80% reduction in the metabolic activity of the biofilm compared to that of the growth control (SMIC50 and SMIC80, respectively). fks mutant Candida isolates formed biofilms in a fashion similar to that of Candida wild-type strains. The echinocandins had the highest activity against biofilms formed by wild-type Candida isolates, followed by fks mutant Candida isolates and non-Candida isolates. Liposomal amphotericin B had the highest activity against fks mutant Candida biofilms. The formation of biofilm by echinocandin-resistant strains was similar to that of wild-type strains, although resistance to echinocandins remained high.
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
authors.forename: Laura Judith
authors.initials: LJ
authors.lastname: Marcos-Zambrano
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Gómez-Perosanz
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Escribano
authors.affiliation: Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain.
authors.forename: Oscar
authors.initials: O
authors.lastname: Zaragoza
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain Medicine Department, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Bouza
authors.affiliation: Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain Medicine Department, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain jguineaortega@yahoo.es.
authors.forename: Jesús
authors.identifier: 0000-0002-7901-8355
authors.initials: J
authors.lastname: Guinea
mesh_terms: D000666:Amphotericin B / Q000494:pharmacology*; D000077612:Anidulafungin; D000935:Antifungal Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D002175:Candida / Q000145:classification / Q000187:drug effects / Q000254:growth & development* / Q000302:isolation & purification; D002177:Candidiasis / Q000188:drug therapy* / Q000382:microbiology; D000077336:Caspofungin; D025141:Drug Resistance, Fungal / Q000235:genetics; D054714:Echinocandins / Q000494:pharmacology*; D005964:Glucosyltransferases / Q000235:genetics; D006801:Humans; D055666:Lipopeptides / Q000494:pharmacology*; D000077551:Micafungin; D008826:Microbial Sensitivity Tests
chemical_list: D000935:Antifungal Agents; D054714:Echinocandins; D055666:Lipopeptides; C068538:liposomal amphotericin B; D000666:Amphotericin B; D000077612:Anidulafungin; D005964:Glucosyltransferases; D000077336:Caspofungin; D000077551:Micafungin