AUTHOR=Guo Penghao , Chen Jianlong , Tan Yiwei , Xia Li , Zhang Weizheng , Li Xiaojie , Jiang Yujie , Li Ruiying , Chen Chunmei , Liao Kang , Peng Yaqin 

TITLE=Comparison of molecular and MALDI-TOF MS identification and antifungal susceptibility of clinical Fusarium isolates in Southern China

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.992582

DOI=10.3389/fmicb.2022.992582

ISSN=1664-302X

ABSTRACT=<sec><title>Background</title><p><italic>Fusarium</italic> species are opportunistic causative agents of superficial and disseminated human infections. Fast and accurate identification and targeted antifungal therapy give help to improve the patients’ prognosis.</p></sec><sec><title>Objectives</title><p>This study aimed to evaluate the effectiveness of matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) for <italic>Fusarium</italic> identification, and investigate the epidemiology and antifungal susceptibility profiles of clinical <italic>Fusarium</italic> isolates in Southern China.</p></sec><sec><title>Methods</title><p>There were 95 clinical <italic>Fusarium</italic> isolates identified by DNA sequencing of translation elongation factor 1-alpha (TEF1α) and MALDI-TOF MS, respectively. Antifungal susceptibility testing of isolates was performed by broth microdilution according to the CLSI approved standard M38-A3 document.</p></sec><sec><title>Results</title><p>Seven species complexes (SC) with 17 <italic>Fusarium</italic> species were identified. The most prevalent SC was the <italic>F. solani</italic> SC (70.5%, 67/95), followed by the <italic>F. fujikuroi</italic> SC (16.8%, 16/95). <italic>F. keratoplasticum</italic> within the <italic>F. solani</italic> SC was the most prevalent species (32.6%, 31/95). There were 91.6% (87/95) of isolates identified by MALDI-TOF MS at the SC level. In most of species, amphotericin B and voriconazole showed lower MICs compared to itraconazole and terbinafine. The <italic>F. solani</italic> SC showed higher MICs to these antifungal agents compared to the other SCs. There were 10.5% (10/95) of strains with high MICs for amphotericin B (≥8 μg/ml), terbinafine (≥32 μg/ml) and itraconazole (≥32 μg/ml) simultaneously, mostly focusing on <italic>F. keratoplasticum</italic> (9/10).</p></sec><sec><title>Conclusion</title><p>MALDI-TOF MS exhibited good performance on the identification of <italic>Fusarium</italic> strains at the SC level. The <italic>F. solani</italic> SC was the most prevalent clinical SC in Southern China. The MICs varied significantly among different species or SCs to different antifungal agents.</p></sec>