Treatment of enterococcal endocarditis requires up to 6 weeks of intravenous (IV) antimicrobial therapy. When susceptible, an ampicillin-based regimen is preferred. Studies evaluating ampicillin stability utilizing high-pressure liquid chromatography have indicated enhanced stability (greater than 24 hours at room temperature), supporting outpatient administration. Thus, we report the successful treatment of a 30-year-old male with tricuspid valve enterococcal endocarditis in an outpatient setting using continuous infusion ampicillin via an ambulatory infusion pump. The patient received daily gentamicin at an outpatient infusion center with the ampicillin dose to be infused over the next 24 hours. Outpatient ambulatory infusion pumps allow for delivery of ampicillin via continuous infusion or pump-programmed pulse dosing. Preparation and administration in an outpatient infusion center may be a viable option to circumvent stability and delivery issues. Furthermore, 81% (34/42) of treatment days were completed outpatient, supporting that this approach may increase access to treatment and help reduce the economic burden to health care.
Keywords: ampicillin; enterococcal endocarditis; infectious disease; infective endocarditis; outpatient parenteral antibiotic therapy.