First Case of Candida Auris Sepsis in Southern Italy: Antifungal Susceptibility and Genomic Characterisation of a Difficult-to-Treat Emerging Yeast

Abstract

Candida auris is an emerging yeast considered a serious threat to global health. We report the first case of C. auris candidemia in Southern Italy, characterized using whole genome sequencing (WGS), and compared with a second strain isolated from a patient who presented as C. auris-colonized following screening. The C. auris strain was isolated from clinical samples, identified via MALDI-TOF, and subjected to WGS. Antifungal susceptibility testing was performed using commercial broth microdilution plates, and resistance protein sequences were evaluated with TBLASTN-2.15.0. Following the initial C. auris isolation from patient A, active surveillance and environmental investigations were implemented for all ICU patients. Of the 26 ICU surfaces sampled, 46.1% tested positive for C. auris via real-time PCR. Screening identified a second patient (patient B) as C. auris-colonized. The phylogenetic characterization of strains from patients A and B, based on the D1/D2 region of the 28s rDNA and the internal transcribed spacer (ITS) region, showed high similarity with strains from Lebanon. SNP analysis revealed high clonality, assigning both strains to clade I, indicating a significant similarity with Lebanese strains. This case confirms the alarming spread of C. auris infections and highlights the need for stringent infection control measures to manage outbreaks.

Keywords

• <i>Candida auris</i>
• whole-genome sequencing
• infection control
• phylogenesis