Effect of standard therapy with vs. without an antistaphylococcal ß-lactam on MRSA bacteremia outcomes

Researchers wondered if supplementing routine antibiotic therapy with a course of antistaphylococcal ß-lactam might reduce the high mortality rate in cases of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia.

Researchers wondered if supplementing routine antibiotic therapy with a course of antistaphylococcal ß-lactam might reduce the high mortality rate in cases of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. To answer their question, the multinational team recruited 352 adults hospitalized with MSRA bacteremia for a randomized study. Approximately one-half of the participants received usual care with I.V. vancomycin or daptomycin, while the others received the same therapy plus a 7-day course of I.V. flucloxacillin, cloxacillin, or cefazolin. Although the trial was terminated early due to increased risk of injury in the intervention group, a total of 345 patients completed the protocol. Among them, 35% of those assigned to combination therapy and 39% of those receiving standard treatment met the primary outcome: a 90-day composite of mortality, persistent bacteremia at day 5, microbiological relapse, and microbiological treatment failure. Based on the evidence, the researchers determined that adding antistaphylococcal ß-lactam to standard antibiotic therapy is not significantly better than usual care alone in treating patients with MRSA bacteremia.