Candida tropicalis: An Emerging Opportunistic Pathogen at the Interface of Virulence, Antifungal Resistance, and Host Immune Interactions

Abstract

Candida tropicalis has emerged as one of the most clinically relevant non-albicans Candida species, owing to its increasing global prevalence, high mortality associated with invasive infections, and rising rates of antifungal resistance. Although traditionally considered an opportunistic pathogen, growing evidence indicates that its remarkable adaptive capacity is driven by the coordinated regulation of multiple biological processes that promote host colonization, persistence, and immune evasion. In this review, we summarize current knowledge on the epidemiology, biology, genomic organization, virulence factors, and host–pathogen interactions of C. tropicalis. Particular emphasis is placed on recent advances in comparative genomics and functional studies that have expanded our understanding of the molecular determinants underlying adhesion, biofilm formation, morphogenesis, extracellular hydrolytic enzyme production, thermotolerance, cell wall remodeling, and immune evasion. We also integrate orthology analyses identifying putative C. tropicalis homologs of well-characterized Candida albicans virulence genes, highlighting the evolutionary conservation of key pathogenic mechanisms while emphasizing species-specific adaptations that remain functionally unexplored. Finally, we discuss current knowledge of antifungal resistance and the emerging relationship between genomic plasticity, stress adaptation, and pathogenicity. Together, this review provides an updated and comprehensive overview of the biological mechanisms that contribute to the success of C. tropicalis as an emerging opportunistic pathogen and identifies key areas requiring further investigation to improve diagnosis, treatment, and the development of novel antifungal strategies.