Species identification and in vitro antifungal susceptibility profile of 39 isolates of Aspergillus section Flavi isolated from nails in Iran

Abstract

Abstract: Objective In this study, species identification and in vitro antifungal susceptibility profile of 39 isolates of Aspergillus section Flavi isolated from onychomycosis in Mashhad, Iran were investigated. Methods β-tubulin/calmodulin gene sequencing combined with MALDI-TOF MS were used for identification of 39 isolates of Aspergillus section Flavi; Antifungal susceptibility to 10 antifungal drugs including terbinafine, new triazole and echinocandins were determined on all the isolates according to CLSI M38-A3. Results Among the 39 Aspergillus section Flavi based on morphological identification, 38 isolates were identified as A. flavus or A. oryzae by molecular method, and identified as A. flavus by MALDI-TOF MS, one isolate was A. minisclerotigenes by molecular method. However, MALDI-TOF MS misidentified one isolate of A.minisclerogenes as A.flavus. The antifungal susceptibility results indicated that terbinafine, posaconazole and echinocandins had good activity against the most Aspergillus isolates tested in this study. Conclusions Molecular identification combined with MALDI-TOF MS could correctly identify Aspergillus section Flavi to species level, particularly for A. flavus/A. oryzae which molecular identification could not differentiated, MALDI-TOF MS could identify correctly. Expanding reference strain database is necessary for precise identification of Aspergillus section Flavito species level. Terbinafine, posaconazole and echinocandins could be potentially effective drugs for the treatment of onycomycosis due to Aspergillus section Flavi.

Key words: non-dermatophytes mold, non-dermatophyte molds onychomycosis, Aspergillus section Flavi, molecular identification, MALDI-TOF-MS, antifungal susceptibility, Iran

CLC Number:

XU Xue, DENG Shuwen, WANG Xiaodong, ZHAO Rongfen, ZHANG Hong, YU Nong, Mohammad Javad Najafzadeh, SHI Dongmei, LU Min. Species identification and in vitro antifungal susceptibility profile of 39 isolates of Aspergillus section Flavi isolated from nails in Iran[J]. Chinese Journal of Mycology, 2021, 16(4): 222-228.

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