Which antibiotic for hospital acquired pneumonia caused by MRSA?

Hospital acquired pneumonia is associated with increased patient morbidity, mortality, and healthcare costs. Outcome is greatly influenced by aspects of antibiotic treatment including the agent chosen, the timing of initiation, adequacy, and duration.1 Gram negative organisms were traditionally thought to be the causal pathogens, but there has been an increasing shift towards Gram positive organisms, particularly Staphylococcus aureus. Surveillance studies have found that 50–60% are meticillin resistant S aureus (MRSA).2 Clinicians treating hospital acquired pneumonia, which is known or suspected to be secondary to MRSA, need to know which antimicrobial agent works best and is least harmful.

Vancomycin was traditionally considered the mainstay of treatment for MRSA, but in the past few years the number of available antimicrobials active against MRSA has increased substantially. Newly available drugs include linezolid, telavancin, tigecycline, quinupristin-dalfopristin, daptomycin, and ceftaroline. Given these available alternatives, how can we optimise the treatment of hospital acquired pneumonia caused by MRSA? Or, to paraphrase, are the newer antibiotics any better or any safer than the old standby vancomycin?

For hospital acquired pneumonia, the seemingly large number of options is quickly reduced because of the pharmacology, inadequate evaluation, possible harm, …