Candida vulturna, the Next Fungal Menace? A Narrative Review

Abstract

Introduction: The yeast Candida vulturna is a member of the Candida haemulonii species complex, like its close relative Candida auris. Members of this species complex, including C. vulturna, often display reduced susceptibility to one or more antifungal classes. Human invasive infections by C. vulturna are increasingly reported in various countries, while the first identification of this fungus, isolated from a flower, occurred less than 10 years ago. The purpose of this review is to compile all reported outbreaks and cases and describe the characteristics of this emerging yeast.

Methods: PubMed, Scopus, Web of Science and Google Scholar were reviewed for publications until April 14, 2025. Records in English were found by using the keyword Candida (Candidozyma) vulturna, and were included if cases were invasive infections.

Results: All reported 94 cases were exclusively from the last 10 years, often in Asian or Latin American countries and included three outbreaks in Brazil, Vietnam and China. Patients displayed diverse clinical characteristics with an overall low mortality rate of 18%. Most studies (n = 11) performed antifungal susceptibility testing (AFST) with microbroth dilution methods and found reduced susceptibility to azoles and amphotericin B. The ERG11^P135S mutation was shown to confer azole resistance, although the mechanism behind amphotericin B resistance has not been uncovered. Identification by MALDI-ToF routinely misidentified C. vulturna as C. pseudohaemulonii or C. duobushaemulonii, leaving molecular identification by ITS sequencing or whole genome sequencing as the only available methods for accurate species determination.

Conclusion: Although C. vulturna is still a rare yeast, cases are increasingly reported in tropical regions. The yeast has outbreak potential, in addition to reduced susceptibility to azoles and amphotericin B. Treatment with echinocandins showed favourable outcomes with a low mortality rate.

Keywords: Candida; antifungal resistance; azoles; invasive fungal infection; multidrug resistance.

FIGURE 1

Geographic overview depicting 103 Candida vulturna cases, including invasive cases from blood (n = 94) and cases from nonsterile sites (n = 8) or environmental samples (n = 1). Figure created with https://www.mapchart.net/.

FIGURE 2

Phylogenetic relatedness between Candida vulturna and related species from the Candida haemulonii species complex is demarcated. The tree was based on internal transcribed spacer sequences rooted to Pichia kudriavzevii. *Can differ greatly between countries. Abbreviations: AMB, amphotericin B; EC, echinocandins; FLU, fluconazole.