New scientific findings shed light on how the dangerous hospital fungus Candidozyma auris evades medical treatment, posing a severe threat to vulnerable intensive care patients where bloodstream infections carry a mortality rate of 45 percent.
Published in the journal Nature Communications, a study led by researchers at the University of Exeter examined a specific resistance mechanism involving a gene known as "Crazy-one" (CRZ1). According to lead author Hugh Gifford, the pathogen can attach to patient skin and medical equipment, spread between humans, and prove extremely difficult to eradicate. When an infection reaches a weakened patient's bloodstream, the mortality rate reaches 45 percent.
The research team investigated why two critically ill patients could not be cured despite treatment with Echinocandins, a class of drugs acting as a first-line defense against the fungus. Through accidental prolonged cultivation of Candidozyma auris with the antifungal medication anidulafungin, researchers observed that a small fraction of cells continued to grow, forming distinct slow-growing and fast-growing colonies. Tests revealed that the fungus survived by generating extra copies of its entire genome, increasing mutation probabilities that led to drug resistance linked to the CRZ1 gene.