In vitro activity of five antifungal agents against Candida albicans isolates, Sari, Iran

Authors

1 Department of Medical Mycology and Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran

2 Department of Medical Laboratory Sciences, School of Paramedicine/Infectious & Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

3 Department of Medical Microbiology, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran

4 Department of Pharmacology, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran

Abstract

Background and Purpose: Candida albicans is the most common causative agent of candidiasis. Candidiasis
management is dependent on the immune status of the host, severity of disease, and the choice of antifungal drug.
Antifungals, specifically triazoles, are widely administered for the treatment of invasive fungal infections. Herein, we
aimed to evaluate the in vitro susceptibility of C. albicans isolates to fluconazole (FLZ), itraconazole (ITZ), voriconazole
(VRZ), amphotericin B (AMB), and Caspofungin (CAS).
Materials and Methods: A total of 44 clinical strains of C. albicans were collected from 36 patients admitted to four
hospitals in Mazandaran Province, Iran. The in vitro antifungal susceptibility testing was performed based on the Clinical
and Laboratory Standards Institute methods.
Results: Generally, 34 isolates were susceptible to all the five antifungal drugs, while four isolates were susceptible or
susceptible dose-dependent (SDD) and six isolates were SDD or resistant to these antifungals. The lowest minimum
inhibitory concentration (MIC; 0.016 μg/ml) belonged to AMB and the highest MIC was for FLZ (16 μg/ml). The lowest
MIC50 (0.063 μg/ml) was related to ITZ and the lowest MIC90 (0.25 μg/ml) pertained to CAS; in addition, the highest
MIC50 (1 μg/ml) and MIC90 (4 μg/ml) were for FLZ. Four of the isolates showed resistance to both FLZ and VRZ,
separately, and five isolates were resistant to ITZ. Caspofungin showed potent activity against more than 95% of the C.
albicans isolates.
Conclusion: Overall, we reported 9.1% resistance to FLZ and VRZ, 11.3% resistance to ITZ and AMB, and 4.6%
resistance to caspofungin. Our finding is in agreement with previous observations proposing that C. albicans isolates
develop resistance to some antifungal drugs such as FLZ since they are widely used as prophylaxis.

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