Emergence of Methicillin-Resistant Staphylococcus aureus (MRSA) as a Public-Health Threat and Future Directions of Antibiotic Therapy for MRSA Infections

Gram-positive cocci are responsible for many severe infections in community and hospital settings, and these multidrug resistant organisms have increased markedly in the past decade. This trend is particularly evident for methicillin/ oxacillin-resistant Staphylococcus aureus (MRSA). MRSA is any strain of Staphylococcus aureus that has developed resistance to beta-lactam antibiotics, which include the penicillins (methicillin, dicloxacillin, nafcillin, oxacillin, etc.) and the cephalosporins. S. aureus strains have developed resistance to almost all antibiotics, thereby complicating disease management. Antibiotics are an essential part of modern medicine and that has helped dramatically in curing patients suffering from bacterial infections. However, emerging antimicrobial resistance in bacteria threatens to undermine the management of bacterial infections. A number of factors, which may promote antimicrobial resistance such as availability of antimicrobials without prescription, suboptimal hygiene, immunosuppression due to malnutrition or HIV, aggressive cancer chemotherapy and an increase in organ transplantation have resulted in hospitalized patients with immune compromise at high risk of nosocomial infections. The emergence of antibiotic-resistant mutants among bacteria is seemingly inevitable, that results in the decreased efficacy and withdrawal of the antibiotic from wide-spread usage. The purpose of this review is to discuss the increase in isolates of multidrug resistant S. aureus which has created an urgent need for the development of new anti-staphylococcal agents.