Which antibiotics cover VRE and what is a key safety concern for the most commonly used option?

• A. Linezolid and quinupristin/dalfopristin; QT prolongation
• B. Linezolid and quinupristin/dalfopristin; thrombocytopenia and serotonin syndrome risk with SSRIs
• C. Daptomycin and Linezolid; risk: myopathy
• D. Vancomycin and Linezolid; risk: nephrotoxicity

Answer: (B)

Antibiotics that cover VRE include linezolid and quinupristin/dalfopristin. Linezolid is a commonly used option because it has reliable activity against VRE and good oral bioavailability, making it versatile for different infection sites. The key safety concern for the most commonly used choice, linezolid, is its potential to cause bone marrow suppression, especially thrombocytopenia, with longer courses. It also has monoamine oxidase–inhibitor activity, which raises the risk of serotonin syndrome if given with SSRIs or other serotonergic drugs. This combination of efficacy against VRE and the notable hematologic and serotonergic safety considerations explains why linezolid is often the preferred agent, while quinupristin/dalfopristin is less commonly used despite its activity against some VRE strains. The other options either involve drugs that don’t consistently cover VRE or emphasize safety concerns that are not the primary issue with the most commonly used agent.