Genomic Insights of Candida krusei, an Emerging Fungal Pathogen With Intrinsic Antifungal Resistance

Candida krusei is diploid, dimorphic, opportunistic yeast belonging to the methylotrophic clade, known for causing infections primarily in immunocompromised individuals. It is globally distributed with variable prevalence across regions and patient populations. C krusei has been associated with several nosocomial outbreaks, particularly in neonatal intensive care units. A key concern is its intrinsic resistance to fluconazole, often resulting in high mortality. The mechanisms of azole resistance are complex and include low affinity of the Erg11p enzyme, overexpression of efflux pumps, and mutations in the ABC11 gene. Additionally, echinocandin resistance has emerged due to mutations in the hotspot regions of the FKS1 gene. Its biofilmforming ability further enhances its survival against antifungal agents and immune responses. This study highlights C krusei as a clinically significant and emerging fungal pathogen, emphasizing the need for enhanced surveillance, molecular monitoring, and continued research to mitigate its growing threat in healthcare settings.