Oral Antibiotics for Bacteremia and Infective Endocarditis: Current Evidence and Future Perspectives

Abstract

Bacteremia and endocarditis are two clinical syndromes that, for decades, were managed exclusively with parenteral antimicrobials, irrespective of a given patient’s clinical condition, causative pathogen, or its antibiotic susceptibility profile. This clinical approach, however, was based on low-quality data and outdated expert opinions. When a patient’s condition has improved, gastrointestinal absorption is not compromised, and an oral antibiotic regimen reaching adequate serum concentrations is available, a switch to oral antibacterials can be applied. Although available evidence has reduced the timing of the oral switch in bacteremia to three days/until clinical improvement, there are only scarce data regarding less than 10-day intravenous antibiotic therapy in endocarditis. Many standard or studied oral antimicrobial dosages are smaller than the approved doses for parenteral administration, which is a risk factor for treatment failure; in addition, the gastrointestinal barrier may affect drug bioavailability, especially when the causative pathogen has a minimum inhibitory concentration that is close to the susceptibility breakpoint. A considerable number of patients infected by such near-breakpoint strains may not be potential candidates for oral step-down therapy to non-highly bioavailable antibiotics like beta-lactams; different breakpoints should be determined for this setting. This review will focus on summarizing findings about pathogen-specific tailoring of oral step-down therapy for bacteremia and endocarditis, but will also present laboratory and clinical data about antibiotics such as beta-lactams, linezolid, and fosfomycin that should be studied more in order to elucidate their role and optimal dosage in this context.

Efficacy of Ceragenins in Controlling the Growth of Oral Microorganisms: Implications for Oral Hygiene Management

“…The importance of ensuring sufficient oral hygiene has been acknowledged in guideline interventions aimed at preventing ventilator-associated pneumonia (VAP) [ 7 , 8 ]. Based on some studies, it might be concluded that infiltration of Streptococcus mutans , as well as S. sanguis , Staphylococcus aureus , and Enterococcus faecalis is a contributing component in the progression of infective endocarditis [ 9 , 10 ] and infective endocarditis-related bacteremia [ 11 , 12 ]. Gram-negative oral bacteria and the subsequent local inflammatory response linked to periodontitis have been also identified as potential contributors to the development of chronic inflammatory disorders including respiratory diseases [ 13 ] and cardiovascular disease [ 14 ].…”