Activity of esomeprazole and fluconazole against Aspergillus fumigatus and Candida albicans: An in vitro study
Keywords:
Proton pump inhibitors, Aspergillus fumigatus, Candida albicans, in vitro investigation, Broth microdilution bioassayAbstract
Background: Fungal infections caused by Aspergillus fumigatus and Candida albicans are a critical clinical challenge in immunocompromised individuals, and drug repurposing policies may improve the antifungal efficacy and overcome resistance.
Aim: This study assessed the interaction of esomeprazole and fluconazole in an in vitro experimental setting against eight clinical isolates of A. fumigatus and four clinical isolates of C. albicans.
Methods: Nineteen sputum samples were collected from tuberculosis patients, of which 12 yielded fungal growth (eight A. fumigatus and four C. albicans), using morphological and molecular identification techniques. Antifungal susceptibility was measured by broth microdilution to determine the median inhibitory concentration (IC50) and minimum fungicidal concentration (MFC) of fluconazole with and without esomeprazole (30 µg/mL). Statistical analyses were performed using an independent samples t-test.
Results: The incorporation of esomeprazole with fluconazole markedly reduced (p < 0.05) the IC50 of the latter against all isolates of both fungal species. The average IC50 of fluconazole against A. fumigatus decreased from 120.96 µg/mL to 17.02 µg/mL when esomeprazole was added, while it decreased from 7.45 µg/mL to 3.90 µg/mL against C. albicans. Also, a marked reduction in MFC values was recorded for most A. fumigatus isolates, with a decrease in the overall mean from 736.00 µg/mL to 166.51 µg/mL (p < 0.01). However, the reduced MFC values for C. albicans were not statistically significant. Conclusion: Esomeprazole markedly enhances fluconazole's antifungal activity in vitro, demonstrating a positive interaction, especially against A. fumigatus.
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