Activity of amphotericin B and anidulafungin, alone and combined, against Candida tropicalis biofilms developed on Teflon (R) and titanium

Autores de IIS La Fe

• Marcelo Ernesto Fernandez Rivero

  Autor

• José Luis Del Pozo León

  Autor

• Amparo Valentín Martín

  Autor

• Victoria Fornés Ferrer

  Autor

• Cecilia Araceli Molina De Diego

  Autor

• Javier Pemán García

  Autor

• Emilia Canton Lacasa

  Autor

Grupos

• Infección Grave

Abstract

Background: Current therapeutic strategies have a limited efficacy against Candida biofilms that form on the surfaces of biomedical devices. Few studies have evaluated the activity of antifungal agents against Candida tropicalis biofilms. Objectives: To evaluate the activity of amphotericin B (AMB) and anidulafungin (AND), alone and in combination, against C tropicalis biofilms developed on polytetrafluoroethylene (teflon -PTFE) and titanium surfaces using time-kill assays. Methods: Assays were performed using the CDC Biofilm Reactor equipped with PTFE and titanium disks with C. tropicalis biofilms after 24 h of maturation. The concentrations assayed were 40 mg/l for AMB and 8 mg/l for AND, both alone and combined. After 24, 48 and 72 h of exposure to the antifungals, the cfu/cm(2) was determined by a vortexing-sonication procedure. Results: AMB reduced biofilm viable cells attached to PTFE and titanium by >= 99% and AND by 89.3% on PTFE and 96.8% on titanium. The AMB +AND combination was less active than AMB alone, both on PTFE (decrease of cfu/cm(2) 3.09 Log(10) vs. 1.08 when combined) and titanium (4.51 vs. 1.53 when combined), being the interaction irrelevant on both surfaces. Conclusions: AMB is more active than AND against C. tropicalis biofilms. Yeast killing rates are higher on titanium than on PTFE surfaces. The combination of AMB plus AND is less effective than AMB alone on both surfaces. (C) 2017 Asociacion Espanola de Micologia. Published by Elsevier Espana, S.L.U. All rights reserved.

Keywords

• Biofilm; Candida tropicalis; Amphotericin B; Anidulafungin; Polytetrafluoroethylene; Titanium