Beyond Minimum Inhibitory Concentrations: Integrating Molecular Resistance Testing for Equitable Management of Vaginal Candidiasis

Vulvovaginal candidiasis affects 75% of women globally, with 5-8% experiencing recurrent episodes in which molecular resistance mechanisms have evolved beyond the conventional minimum inhibitory concentration (MIC) testing capabilities. A targeted literature review spanning 2000-2025 revealed three distinct evolutionary phases of antifungal resistance: efflux overexpression (2004-2006), regulatory diversification (2007-2016), and network synergy (2019-2025). Current clinical isolates harbor combined resistance mechanisms, including ERG11 mutations (Y132F, K143R) and efflux pump overexpression (CDR1, CDR2, and MDR1), regulated by the transcription factors TAC1 and MRR1. Evidence from African surveillance supports the global distribution of these mechanisms, highlighting the urgent need for molecular diagnostics in resource-limited settings, where Candida auris outbreaks have reached alarming mortality rates. These molecular changes often precede the manifestation of phenotypic resistance, creating diagnostic blind spots where isolates appear "susceptible" by MIC testing but demonstrate clinical treatment failure. Integrating PCR-based molecular diagnostics targeting key resistance genes represents a paradigm shift toward proactive resistance detection and personalized antifungal therapy, addressing healthcare equity in resource-limited settings where disease burden and mortality are disproportionately high.