Reducing resistance to beta-lactam antibiotics: A new treatment strategy for MRSA infections

Approximately 5-10% of hospitalised patients acquire an infection in hospital. Serious infections are more likely in intensive care unit (ICU) or high dependency unit (HDU) patients, in whom implanted medical devices are required for life maintaining therapy. Unfortunately such devices also represent an opportunity for pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) to attach and cause device-related infections (DRIs), which involve biofilms or communities of attached bacterial cells that are highly resistant to antibiotics and our natural defences. Rates of bloodstream infection caused by Staphylococcus aureus (the family of bacteria that includes MRSA) in Irish hospitals are among the highest in Europe and are recognised by both healthcare professionals and the general public as a serious threat to patients. A major limitation of current treatment regimes for DRIs is that the antimicrobial drugs used are selected for their ability to inhibit or kill free floating cells and have limited effectiveness against bacteria such as MRSA within the biofilm structure. New drugs to prevent or treat these infections are urgently needed. In this proposed project, we will investigate the potential of novel treatment strategies to interfere with pathogen signalling systems that control antibiotic resistance, biofilm and virulence. Specifically, using a new approach, our experiments are aimed at reducing antibiotic resistance levels in MRSA, opening up the possibility of using methicillin-type antibiotics alone or in combination with other antibiotics to treat staphylococcal infections that would previously have been considered resistant to these agents. Thus new therapeutic strategies arising from this project will have the potential to improve the management of difficult-to-treat device-related infections, pneumonia, wound infections and infective endocarditis, all of which can be caused by MRSA.

Award Date
21 October 2016
Award Value
€323,798
Principal Investigator
Professor James O'Gara
Host Institution
National University of Ireland, Galway
Scheme
Health Research Awards