According to findings in The Open Access Journal PLoS Pathogens on September 8th, researchers at the University of Toronto have developed a therapy for a potentially deadly type of infection commonly found in catheters, artificial joints and other ‘internal’ medical devices, which are composed of biofilms (complex groupings of cells that attach to surfaces) and coated in a viscous drug resisting matrix that makes treating fungal infections difficult.
Patients, whose catheter or other device has become infected often require surgery to remove the infected device in an attempt to clear the disease and to prevent the infection from spreading.
The researchers successfully managed to overcome the drug resistance in the two main human fungal pathogens, Candida albicans and Aspergillus fumigatus by inhibiting the function of Hsp90, a type of protein.
The authors explain that fungal pathogens are seen as a serious clinical problem. Candida albicans is the third-leading cause of intravascular catheter-related infections and is fatal in about 30% of infections associated with devices. Over the last two decades the number of acquired fungal bloodstream infections has increased by over 200%. This is partly due to successful treatments for previously fatal diseases like cancer and AIDS that have left many patients immune-compromised and susceptible to infection.
Study leader, Prof. Leah Cowen, who holds the Canada Research Chair in Microbial Genomics and Infectious Disease at U of T’s Department of Molecular Genetics said:
“It takes classic antifungals, which were not effective against biofilms, and makes them very effective.”
In an animal experiment, the researchers managed to completely clear a central venous catheter of a deadly fungal infection by blocking Hsp90 and applying antifungals.
Over 10 million patients receive medical devices, such as catheters and artificial joints every year. In view of this, a better understanding of biofilms and their impact on drug resistance of fungal pathogens is of vital importance.
Written by Petra Rattue