MALDI-TOF MS-Based Clustering and Antifungal Susceptibility Tests of Isolates from Fujian and Guangxi (China).

INTRODUCTION

is a life-threatening pathogen that causes systemic talaromycosis in immunocompromised and acquired immunodeficiency syndrome (AIDS) patients. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a tool to cluster isolates is rarely reported and the data on antifungal susceptibility of isolated in the southern region of China, especially in Fujian, is hardly found.

METHODS

MALDI-TOF MS was used to cluster 135 isolates, and the minimum inhibitory concentration (MIC) values of amphotericin B, itraconazole, posaconazole, voriconazole, fluconazole, anidulafungin, micafungin, caspofungin and 5-fluorocytosine with Sensititre YeastOne™ YO10 assay were measured during January 2017 to October 2020 in Fujian and Guangxi.

RESULTS

MALDI-TOF MS correctly identified 100% of the isolates. Hierarchical clustering of MALDI-TOF peak profiles identified four different clusters. MICs for itraconazole, posaconazole, voriconazole and amphotericin B were as follows: ≤0.015-0.03 μg/mL, ≤0.008-0.03 μg/mL, ≤0.008-0.06 μg/mL, ≤0.12-1 μg/mL, respectively. MICs for echinocandins and fluconazole were comparatively high.

CONCLUSION

Since only simple sample preparation is required and since results are available in a short period of time, MALDI-TOF MS can be considered as a method for identification and clustering of . Itraconazole, posaconazole, voriconazole and amphotericin B can be used to treat infected patients due to the low MICs.