Frequency of biocide resistance genes, antibiotic resistance and the effect of chlorhexidine exposure on clinical methicillin-resistant Staphylococcus aureus isolates.

Objectives: To detect genes conferring resistance to biguanides, quaternary ammonium compounds, beta-lactams and fluoroquinolones in clinical methicillin-resistant Staphylococcus aureus (MRSA) and to demonstrate whether reduced susceptibility is spread clonally and if the presence of any of the detected genes links to a specific epidemic MRSA. Finally, to identify if exposure to chlorhexidine may cause reduced susceptibility to antibiotics and chlorhexidine.

Methods: In total, 120 clinical MRSA isolates were isolated.