Antifungal resistance occurs when pathogenic fungi can grow or survive despite exposure to an antifungal medicine that would normally inhibit or kill them. This loss of susceptibility is an emerging public health threat【789199571224237†L87-L95】.
Explanation
Fungal infections range from superficial skin conditions to life‑threatening systemic diseases. To treat them, clinicians rely on a limited arsenal of drugs—principally polyenes, azoles, echinocandins and allylamines—that target fungal cell membranes or cell wall synthesis. Antifungal resistance arises when fungi develop genetic changes that reduce a drug’s efficacy, such as mutations in drug targets, overexpression of efflux pumps or biofilm formation. Overuse and misuse of antifungals in medicine and agriculture create selective pressure that favours resistant strains【789199571224237†L135-L151】. Some species, including Candida krusei and Aspergillus terreus, are intrinsically resistant to certain agents, while others acquire resistance through mutations after exposure. Inadequate dosing, premature discontinuation of therapy or self‑medication can all contribute to the emergence of resistant infections【789199571224237†L135-L151】. Resistance is particularly concerning in resource‑limited settings where diagnostics and drug options are scarce【789199571224237†L101-L117】. The spread of resistant strains threatens immunocompromised patients, who are most susceptible to invasive candidiasis and aspergillosis.
Notable examples and drivers
One widely publicised example is Candida auris, an emerging yeast that causes invasive bloodstream infections and exhibits resistance to multiple antifungal classes【789199571224237†L155-L161】. Its ability to persist on surfaces has led to hospital outbreaks worldwide. Candida albicans and C. glabrata can develop azole resistance during prolonged therapy, and some isolates also show decreased susceptibility to echinocandins. Environmental use of triazole fungicides in agriculture has led to cross‑resistant Aspergillus fumigatus strains that infect humans【789199571224237†L135-L151】. Inherent resistance of C. krusei to fluconazole and of Aspergillus terreus to amphotericin B further limits treatment choices. Addressing these challenges requires stewardship programmes, surveillance, improved diagnostics and development of new antifungal agents.
Antifungal resistance underscores the importance of prudent antifungal use and ongoing research to stay ahead of evolving fungal pathogens.
Related Terms: Antifungals, Fungi, Candidiasis, Azoles, Echinocandins