Fluconazole, itraconazole and ketoconazole in-vitro activity. A comparative study

Area of Science:

• Mycology
• Infectious Diseases
• Pharmacology

Background:

• Antifungal resistance is a growing concern, particularly in immunocompromised populations like patients with AIDS.
• Azole antifungal drugs are commonly used to treat fungal infections in these patients.
• Understanding the in-vitro activity of different azoles is crucial for guiding clinical treatment decisions.

Purpose of the Study:

• To compare the in-vitro activity of fluconazole, itraconazole, and ketoconazole.
• To determine the Minimal Inhibitory Concentrations (MICs) of these azole antifungals against fungal strains from ARC/AIDS patients.

Main Methods:

• Evaluated in-vitro activity using Minimal Inhibitory Concentrations (MICs).
• Tested 100 fungal strains isolated from biological specimens of ARC/AIDS patients.
• Employed a semisolid agar medium suitable for yeasts and molds, applicable to all azole antifungal drugs.

Main Results:

• Fluconazole exhibited higher MICs compared to itraconazole and ketoconazole, especially against Candida krusei strains.
• Fluconazole's MICs never exceeded 40 mg/l.
• One Cryptococcus neoformans strain showed MICs above 40 mg/l for both itraconazole and ketoconazole.
• No significant differences in MICs were observed between itraconazole and ketoconazole across the tested strains.

Conclusions:

• Fluconazole demonstrates lower in-vitro activity against certain fungal strains, including Candida krusei, compared to itraconazole and ketoconazole.
• Itraconazole and ketoconazole show comparable in-vitro efficacy against the tested fungal isolates from ARC/AIDS patients.
• The findings highlight the importance of susceptibility testing for azole antifungals in immunocompromised patients.