Clinical question: Does transitioning to oral antibiotics to treat infective endocarditis increase rates of relapse and death?
Background: Treating infective endocarditis with four to six weeks of intravenous antibiotics carries a high cost. There are data to support oral antibiotics for right-sided endocarditis due to methicillin-sensitive Staphylococcus aureus (with ciprofloxacin and rifampicin), but experience in using oral antibiotics for infective endocarditis is limited.
Study design: Cohort study.
Setting: Large academic hospital in France.
Synopsis: The researchers included 426 patients with definitive or probable endocarditis by Duke criteria. After an initial period of treatment with intravenous (IV) antibiotics, 50% of the identified group was transitioned to oral antibiotics (amoxicillin alone in 50% and combinations of fluoroquinolones, rifampicin, amoxicillin, and clindamycin in the others).
The risk of death was not increased in the group treated with oral antibiotics when adjusted for the four biggest predictors of death (age >65, type 1 diabetes mellitus, disinsertion of prosthetic valve, and endocarditis due to S. aureus). Nine patients treated with IV antibiotics experienced relapsed endocarditis compared to two patients treated with oral antibiotics.
Patients selected for treatment with oral antibiotics were less likely to have severe disease, significant comorbidities, or infection with S. aureus. The length of treatment with IV antibiotics before switching to oral antibiotics varied widely.
Bottom line: It’s possible low-risk patients with infective endocarditis may be treated with oral antibiotics, but more data are needed.
Citation: Mzabi A, Kernéis S, Richaud C, Podglajen I, Fernandez-Gerlinger MP, Mainardi, JL. Switch to oral antibiotics in the treatment of infective endocarditis is not associated with increased risk of mortality in non-severely ill patients [published online ahead of print April 16, 2016]. Clin Microbiol Infect. doi:10.1016/j.cmi.2016.04.003.