Reviewed by Jose Lucar, MD, The George Washington University
The Centers for Disease Control and Prevention (CDC) has identified azole resistance in Candida species as a significant public health threat. Recent data highlight a troubling rise in resistance within the Candida parapsilosis complex in the United States. Researchers analyzed antifungal susceptibility results from 1,740 C. parapsilosis bloodstream isolates submitted to a major U.S. reference laboratory between January 2015 and September 2024. Their findings revealed a significant increase in fluconazole resistance, rising from 8.2% to 20.3% over the study period (odds ratio [OR] per year: 1.13; 95% confidence interval [CI]: 1.06–1.20). This trend accelerated notably beginning in 2021. Although voriconazole resistance showed a non-significant upward trend, micafungin resistance remained rare (0.5%). However, the proportion of isolates with intermediate susceptibility to micafungin increased significantly (OR per year: 1.42; 95% CI: 1.25–1.63). The authors suggest performing antifungal susceptibility testing on C. parapsilosis blood isolates before switching from an echinocandin to fluconazole. They also emphasize the critical need for continued surveillance and robust antifungal stewardship to preserve treatment efficacy.
Reference:
McHugh J, Chesdachai S, Dunsirn M, Wengenack N, Vergidis P. Increasing Fluconazole Resistance in Candida parapsilosis: A 10-Year Analysis of Blood Culture Isolates at a US Reference Laboratory (2015-2024). J Infect Dis. Published online May 13, 2025. doi:10.1093/infdis/jiaf249