Nosocomial fungemia by Candida auris: First four reported cases in continental Europe

Abstract

Background: Candida auris is an emerging multidrug-resistant yeast that can cause invasive infections and is associated with high mortality. It is typically resistant to fluconazole and voriconazole and, some cases, also to echinocandins and amphotericin B. This species, phylogenetically related to Candida haemulonii, is frequently misidentified by commercial identification techniques in clinical laboratories; therefore, the real prevalence of C. auris infections may be underestimated.

Aims: To describe the clinical and microbiological features of the first four cases of C. auris fungemia episodes observed in the European continent.

Methods: The four patients were hospitalized in the adult surgical intensive care unit. A total of 8 isolates (two per patient) from blood and catheter tip were analyzed.

Results: All isolates were misidentified as Saccharomyces cerevisiae by AuxaColor 2, and as Candida sake by API ID20C. VITEK MS technology misidentified one isolate as Candida lusitaniae, another as C. haemulonii and could not identify the other six. C. auris identification was confirmed by ITS rDNA sequencing. All isolates were fluconazole (MIC >256mg/l) and voriconazole (MIC 2mg/l) resistant and susceptible to posaconazole, itraconazole, echinocandins and amphotericin B.

Conclusions: C. auris should be regarded as an emerging pathogen, which requires molecular methods for definitive identification. Our isolates were highly resistant to fluconazole and resistant to voriconazole, but susceptible to the other antifungals tested, which emphasizes the importance of accurately identifying this species to avoid therapeutic failures.

Keywords: Candida auris; Candidemia; Cuidados intensivos quirúrgicos; Fluconazole resistance; Fungemia; Resistencia al fluconazol; Surgical intensive care.