Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric identification and antifungal susceptibility analysis of Candida species isolated from patients with invasive yeast infections in five university hospitals

• Published in: Brazilian journal of microbiology 2019-01, Vol.50 (1), p.99-105
• Main Authors: Hu, Zhimin, Zhang, Juling, Chen, Zhongju, Jin, Zhengjiang, Leng, Pei, Zhou, Junying, Xie, Xiaofang
• Format: Article
• Language: English
• Subjects: Antifungal Agents - pharmacology; Azoles; Azoles - pharmacology; Biomedical and Life Sciences; Candida; Candida - classification; Candida - drug effects; Candida - genetics; Candida - isolation & purification; Candida albicans; Candidemia; Candidiasis - microbiology; Cerebrospinal fluid; Clinical isolates; Clinical Microbiology - Research Paper; Desorption; Food Microbiology; Fungi; Fungicides; Heterocyclic compounds; Hospitals, University; Humans; Identification; Ionization; Ions; Life Sciences; Mass spectrometry; Mass spectroscopy; Medical Microbiology; Microbial Ecology; Microbial Genetics and Genomics; Microbial Sensitivity Tests; Microbiology; Mycological Typing Techniques - methods; Mycology; Patients; Spacer; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Surgery; Yeast; Yeasts
• ISSN: 1517-8382; 1678-4405
• DOI: 10.1007/s42770-018-0027-0

In this multicenter study, we compared the performance of the Bruker Biotyper MS system and VITEK 2 YST systems for invasive yeast identification, investigated the distribution of isolated species, and evaluated the antifungal susceptibility profiles of Candida albicans , Candida parapsilosis , and Candida tropicalis . In cases of discrepant results lack of identification with either method, molecular identification techniques were employed. We tested 216 clinical isolates, and concordance between the two methods was observed for 192/216 isolates (88.9%). For five unidentified strains (2.3%), an internal transcribed spacer (ITS) sequencing approach was used. In brief, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) provided short turnaround times and more reliable results than those of Vitek 2 YST. In Wuhan, C . albicans , C . parapsilosis , Candida glabrata , and C . tropicalis were the most common pathogens (93.0%) in patients with candidemia. Cryptococcus neoformans was mainly detected in cerebrospinal fluid samples (88.9%). Trichosporon asahii were all isolated from drainage fluids in the Surgery. Candida albicans was clearly susceptible to azoles, while C . parapsilosis and C . tropicalis displayed differences in susceptibility to azoles. Our findings provide a basis for the practical application of MALDI-ToF MS for identification and for the use of ATB FUNGUS 3 to characterize the susceptibility of Candida spp., thereby providing significant data for therapeutic decisions.