Emergence of Flucytosine-Resistant Candida tropicalis Clade, the Netherlands
File(s)
Author(s)
Type
Journal Article
Abstract
Candida tropicalis is the second most virulent Candida species after C. albicans. Previous studies from the Netherlands and France reported a notable reduction in susceptibility to flucytosine (5-FC) in a substantial proportion of C. tropicalis isolates. We investigated epidemiologic patterns of C. tropicalis isolates in the Netherlands and the genetic mechanisms driving widespread non–wild-type (WT) 5-FC resistance. We conducted antifungal susceptibility testing and used advanced molecular techniques, including short tandem repeat genotyping and whole-genome sequencing paired with single-nucleotide polymorphism analysis, to analyze 250 C. tropicalis isolates collected across the Netherlands during 2012–2022. Our findings revealed the rapid emergence of a 5-FC–resistant, non-WT C. tropicalis clade, accounting for >40% of all C. tropicalis isolates by 2022. Genomic analysis identified a homozygous nonsense mutation in the FCY2 gene, which was exclusive to this non-WT population. Continued surveillance efforts are needed to detect and prevent the spread of drug-resistant Candida species.
Date Issued
2025-07-01
Date Acceptance
2025-06-01
Citation
Emerging Infectious Diseases, 2025, 31 (7), pp.1354-1364
ISSN
1080-6040
Publisher
Centers for Disease Control and Prevention (CDC)
Start Page
1354
End Page
1364
Journal / Book Title
Emerging Infectious Diseases
Volume
31
Issue
7
Copyright Statement
All materials published in Emerging Infectious Diseases, including text, figures, tables, and photographs, are in the public domain and can be reprinted or used without permission with proper citation. All content is freely available without charge to the user or their institution. In accordance with the Budapest Open Access Initiative definition of open access, users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. Because the journal is in the public domain, its usage policy also conforms to conditions set forth by Creative Commons.
Subjects
Humans
Candida tropicalis
Candidiasis
Flucytosine
Antifungal Agents
Microbial Sensitivity Tests
Drug Resistance, Fungal
Genotype
Polymorphism, Single Nucleotide
Netherlands
Female
Male
Whole Genome Sequencing
Publication Status
Published
Date Publish Online
2025-06-11