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Updated: May 23, 2026
08:24
Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans
Published on: February 27, 2018
Extensive genetic diversity within the Dutch clinical Cryptococcus neoformans population
Ferry Hagen1, María-Teresa Illnait-Zaragozí, Jacques F Meis
1Department of Yeast and Basidiomycete Research, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands.
Journal of Clinical Microbiology
|March 24, 2012
Summary
This study analyzed 300 Dutch Cryptococcus neoformans isolates, finding mating type alpha and serotype A were most common. Antifungal susceptibility testing revealed lower efficacy for fluconazole and flucytosine.
Area of Science:
- Medical Mycology
- Infectious Diseases
- Genetics
Background:
- Cryptococcus neoformans is an opportunistic fungal pathogen.
- Infections predominantly affect immunocompromised individuals, including those with HIV/AIDS.
- Understanding genotypic diversity and antifungal resistance is crucial for effective treatment.
Purpose of the Study:
- To characterize a collection of Dutch Cryptococcus neoformans isolates.
- To determine mating types, serotypes, and genotypes (AFLP, microsatellite).
- To assess antifungal susceptibility profiles against seven antifungal agents.
Main Methods:
- Isolates were obtained from patients between 1977 and 2007.
- Mating type, serotype, AFLP, and microsatellite genotyping were performed.
- Antifungal susceptibility testing determined minimum inhibitory concentrations (MICs).
Main Results:
- The majority of isolates were mating type alpha and serotype A.
- AFLP1 was the most prevalent genotype, with high genetic diversity in serotype A isolates.
- Fluconazole and flucytosine exhibited the highest geometric mean MICs, with some isolates showing reduced susceptibility.
Conclusions:
- The study provides insights into the genetic landscape and antifungal resistance of Cryptococcus neoformans in the Netherlands.
- Serotype A isolates, particularly those with mating type alpha, are common.
- Emerging resistance or reduced susceptibility to fluconazole and flucytosine warrants monitoring.
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