Treatment of prosthetic valve endocarditis (PVE) is more difficult than treatment of native valve endocarditis (NVE) and may require surgical replacement of the prostheses in addition to antibiotic therapy.
The antimicrobial regimens used are targeted to a specific pathogen; thus, identification of the causative organism is critical.
We recommend the same treatment regimens for a specific pathogen causing PVE as is used for that organism when it causes native valve endocarditis (Grade 1B). An exception is staphylococcal endocarditis; for this microorganism, we recommend treatment with three agents in combination, with one of these being rifampin (Grade 1B).
We recommend treatment of PVE with an agent(s) that is bactericidal for the isolated microorganism for at least six weeks (Grade 1C).
Treatment choices for staphylococcal PVE are the same regardless of whether the pathogen is coagulase-negative Staphylococcus or S. aureus. The primary consideration in choosing therapy hinges upon whether or not the organism is sensitive to methicillin.
We recommend a treatment regimen for enterococcal PVE that includes the synergistic interaction of a cell wall active agent (penicillin, ampicillin, or vancomycin) and an aminoglycoside (gentamicin or streptomycin) if possible (Grade 1B). When these combinations are precluded by the resistance pattern of the organism or the patient’s risk for aminoglycoside nephrotoxicity, the high-dose ceftriaxone-ampicillin is a reasonable alternative regimen.