A 40-Year Antifungal Susceptibility Surveillance of Talaromyces marneffei (1984–2024) at a Tertiary Hospital in Guangxi, China

Abstract Long-term trends in the antifungal susceptibility of Talaromyces marneffei isolates have not been well characterized. We conducted a 40-year surveillance study analyzing the antifungal susceptibility of 131 T. marneffei isolates collected from the clinical laboratory of the First Affiliated Hospital of Guangxi Medical University between 1984 and 2024. In vitro susceptibilities to conventional antifungal agents, including itraconazole, voriconazole, fluconazole and amphotericin B, were analyzed using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. We also explored the potential influence of host HIV status and fungal mating type (MAT) on susceptibility patterns. The minimum inhibitory concentrations (MICs) for itraconazole, voriconazole, fluconazole, and amphotericin B ranged from 0.015 to 0.06 μg/mL, 0.008 to 0.03 μg/mL, 1 to 8 μg/mL, and 0.25 to 1 μg/mL, respectively. Fluconazole showed a significant decline in susceptibility over time (p < 0.01), whereas the susceptibilities to the other antifungals remained stable (p > 0.05). The correlations observed between the MICs of different triazoles (p < 0.01) suggest potential cross-resistance among triazoles. Mating type and HIV infection status did not significantly affect antifungal susceptibility patterns (p > 0.05). These findings underscore the importance of ongoing antifungal susceptibility surveillance in T. marneffei, considering the changes in fluconazole susceptibility and potential triazole cross-resistance, while other antifungals remain stable.