Antibiotic resistance in Staphylococcus aureus: concerns, causes and cures.

Methicillin-resistant Staphylococcus aureus (MRSA) is currently a predominant and dangerous nosocomial pathogen. Unfortunately, infections caused by this organism are becoming more difficult to treat as further evolution of drug resistance occurs within the pathogen. Vancomycin has become the drug of choice for treating MRSA infections. However, treatment failures, adverse side effects and the emergence of vancomycin-resistant MRSA are leading to urgent requirements for alternative antiMRSA therapies. Linezolid is a new agent recently developed for Gram-positive infections, including MRSA. However, resistance to this drug is already developing. The need for superior antiMRSA drugs is therefore highly evident. This article explores some of the opportunities for the development of new treatments for MRSA. These arise principally from extensions of existing drug classes and the discovery of novel agents by genome-driven technologies. Other possibilities concern the re-evaluation of earlier pharmacophores that have not so far been developed as antiMRSA agents.