In vitro activities of antifungals alone and in combination with tigecycline against Candida albicans biofilms

Mayram Hacioglu; Ayse Seher Birteksoz Tan; Sibel Dosler; Nese Inan; Gulten Otuk

doi:10.7717/peerj.5263

In vitro activities of antifungals alone and in combination with tigecycline against Candida albicans biofilms

PeerJ. 2018 Jul 25:6:e5263. doi: 10.7717/peerj.5263. eCollection 2018.

Authors

Mayram Hacioglu¹, Ayse Seher Birteksoz Tan¹, Sibel Dosler¹, Nese Inan², Gulten Otuk¹

Affiliations

¹ Department of Pharmaceutical Microbiology, Istanbul University, Istanbul, Turkey.
² Department of Microbiology, Faculty of Medicine, Istanbul Bilim University, Istanbul, Turkey.

Abstract

Background: Candida may form biofilms, which are thought to underlie the most recalcitrant infections.

Methods: In this study, activities of antifungal agents alone and in combination with tigecycline against planktonic cells and mature and developing biofilms of Candida albicans isolates were evaluated.

Results: Amphotericin B and echinocandins were found to be the most effective agents against mature biofilms, whereas the least effective agent was fluconazole. Furthermore, the most effective anti-fungal monotherapies against biofilm formation were amphotericin B and anidulafungin, and the least effective monotherapy was itraconazole. The combination of tigecycline and amphotericin B yielded synergistic effects, whereas combinations containing itraconazole yielded antagonist effects against planktonic cells. The combination of tigecycline and caspofungin exhibited maximum efficacy against mature biofilms, whereas combinations containing itraconazole exhibited minimal effects. Combinations of tigecycline with amphotericin B or anidulafungin were highly effective against C. albicans biofilm formation.

Discussion: In summary, tigecycline was highly active against C. albicans particularly when combined with amphotericin B and echinocandins.

Keywords: Antifungal; Biofilm; Candida albicans; Tigecycline; XTT.

Grants and funding

This work was supported by the Research Fund of Istanbul University (project number 32917). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.