Danish Whole-Genome-Sequenced Candida albicans and Candida glabrata Samples Fit into Globally Prevalent Clades.

Judit Szarvas,Pimlapas Leekitcharoenphon,Turid Snekloth Søndergaard,Niels Frimodt-Møller,Valeria Bortolaia,Hans Linde Nielsen,John Eugenio Coia,Michael Kemp,Frank Møller Aarestrup,Niels Nørskov-Lauritsen,Henrik Westh,Ana Rita Rebelo,Dennis Schrøder Hansen,Bent Løwe Røder,Claus Østergaard

doi:10.3390/jof7110962

Abstract

Candida albicans and Candida glabrata are opportunistic fungal pathogens with increasing incidence worldwide and higher-than-expected prevalence in Denmark. We whole-genome sequenced yeast isolates collected from Danish Clinical Microbiology Laboratories to obtain an overview of the Candida population in the country. The majority of the 30 C. albicans isolates were found to belong to three globally prevalent clades, and, with one exception, the remaining isolates were also predicted to cluster with samples from other geographical locations. Similarly, most of the eight C. glabrata isolates were predicted to be prevalent subtypes. Antifungal susceptibility testing proved all C. albicans isolates to be susceptible to both azoles and echinocandins. Two C. glabrata isolates presented azole-resistant phenotypes, yet all were susceptible to echinocandins. There is no indication of causality between population structure and resistance phenotypes for either species.

Highlights

Seven C. albicans isolates showed increased Minimum Inhibitory Concentration (MIC) to echinocandins when compared with the respective European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoints: all seven appeared resistant to anidulafungin, and one was resistant to micafungin
We sequenced clinical Candida isolates collected during one day in Denmark, from which the majority of the isolates were typed to be C. albicans (n = 30), followed by C. glabrata (n = 8)
C. glabrata candidemia in the country, only a limited number of our isolates were isolated from blood

Summary

Introduction

Opportunistic fungal infections are an increasing concern in hospital settings, as invasive infections and fungemia have a high rate of mortality. A majority of these infections are caused by Candida species, and the incidence of invasive candidiasis has been rising worldwide in recent decades [1]. Denmark is not an exception to this, and the incidence rate has stabilized at around 8/100,000 inhabitants, it remains higher than in other Nordic countries [2]. Candida species normally colonize the skin, intestines, or mucosal surfaces, but may cause disseminated infections in immunocompromised individuals [5]. The most common species causing candidemia is Candida albicans, but the species’ composition shows a changing pattern, with Candida glabrata and Candida parapsilosis infections becoming more prevalent [1,4,6,7]

Methods

Results

Conclusion