Vancomycin- and methicillin-resistant gram-positive cocci have emerged as an increasingly problematic cause of hospital-acquired
infections. We conducted a literature review of newer antibiotics with activity against vancomycin-resistant and methicillin-resistant
gram-positive cocci. Quinupristin/dalfopristin, linezolid, daptomycin, and tigecycline have
in vitro activity for methicillin-resistant staphylococci and are superior to vancomycin for vancomycin-resistant isolates. Dalbavancin,
telavancin, and oritavancin are new glycopeptides that have superior pharmacodynamic properties compared to vancomycin. We
review the antibacterial spectrum, clinical indications and contraindications, pharmacologic properties, and adverse events
associated with each of these agents. Daptomycin has rapid bactericidal activity for
Staphylococcus aureus and is approved for use in bacteremia and right-sided endocarditis. Linezolid is comparable to vancomycin in patients with
methicillin-resistant
S. aureus (MRSA) pneumonia and has pharmacoeconomic advantages given its oral formulation. Quinupristin/dalfopristin is the drug of
choice for vancomycin-resistant
Enterococcus faecium infections but has no activity against
Enterococcus
faecalis. Tigecycline has activity against both enterococcus species and MRSA; it is also active against
Enterobacteriaceae and anaerobes which allows for use in intra-abdominal and diabetic foot infections. A review of numerous
in vitro and animal model studies shows that interaction between these newer agents and other antistaphylococcal agents for
S. aureus are usually indifferent (additive).