Probing insight into antimicrobial resistant fungus

A major systematic review of the pathogenic fungus Candida auris has been conducted. This yeast-like fungus has been found in hospitals and it is resistant to several classes of antimicrobial drugs. This poses serious risks for those infected.

A new report has looked at the spread of the fungus and the mechanisms by which the organism is resistant to antimicrobial substances. The aim is to find a crack in the fungus’ armor and to find effective ways to eliminate infections. The new research has focused on information relating to C. auris drug resistance and growth patterns. The outcome is that a new drug, still at the trial stage and called SCY-078, might be the best candidate for curing infections.

The fungus was cam to attention in 2009 (where C. auris was isolated from the ear canal of a patient at a hospital in Japan). Since then it has been linked to invasive infections in nine countries, where a big risk is the presence of the fungus on medical devices like catheters. In those infected C. auris can cause what is known as fungemia, yielding candidemia (systemic candidiasis). Fungemia is the presence of fungi in the blood. Symptoms associated with fungemia, including pain, acute confusion, chronic fatigue, and infections. The fungus produces destructive enzymes that help the fungus to establish infections in body tissue.

With the new candidate drug, Professor Mahmoud Ghannoum, who works at Case Western Reserve School of Medicine, said: “This emerging fungal species has started to infect patients globally, causing invasive infections that are associated with a high death rate.”

He adds further: "It is multidrug-resistant, and some strains isolated from patients are resistant to all commercially available antifungal drugs. Multidrug-resistance used to be reported for bacteria only, and now we must add fungi to the list.”

To the study the fungal-drug interaction, Professor Ghannoum’s team looked at 16 strains of C. auris collected from infected patients in Germany, Japan, Korea, and India. These strains were then tested against a battery of 11 drugs. This was to identify suitable classes and drug concentrations that could combat infection. This showed that SCY-078 was the most promising. This drug acts to distort the fungus and impairs its growth, preventing it from dividing. The new finding paves the way for experimental trials using the drug to begin.

The research has been published in the journal Antimicrobial Agents and Chemotherapy. The research paper is titled “The Emerging Candida auris Characterization of Growth Phenotype, Virulence Factors, Antifungal Activity, and Effect of SCY-078, a Novel Glucan Synthesis Inhibitor, on Growth Morphology and Biofilm Formation.”

Posted by Dr. Tim Sandle