Antibiotic Prophylaxis of Infective Endocarditis: A Scoping Review

Abstract

Introduction: Infective endocarditis is a rare fatal infection, affecting around 5-10 people per 100,000 per annum. Consequently, this is a disease that is important to prevent using antibiotic prophylaxis. However, the rationale for antibiotic prophylaxis to help prevent IE is itself surrounded by controversy, as there is no definitive evidence for its efficacy.
Methods: An electronic search was conducted in the Medline, Embase, and Cochrane Central Register of Controlled Trials. Search terms used included subject headings and title/abstract keywords for bacterial endocarditis, antibiotics, and prophylaxis. We also searched the reference lists of all included articles. The primary outcome of interest was the incidence of IE, the incidence of (any) bacteremia, or for time-trend studies, the population-adjusted incidence of IE. Where the total incidence of bacteremia was not reported, the time point at which the highest incidence of bacteremia was observed in the placebo group was used for comparison.
Results: The electronic search identified 830 articles, after the removal of case reports, editorials, animal studies, and duplicates. After screening the title and/or abstract of these, 27 articles were deemed eligible for full-text assessment. In total, 16 studies were considered suitable for inclusion. All identified trials used bacteremia as a surrogate endpoint for IE. We identified 10 studies assessing the effect of changing national and international guidelines concerning the use of AP on the population incidence of IE. These included nine studies of relative AP restriction (from the USA and Europe) and one study examining the effect of total AP restriction (from the UK).
Conclusions: The adequacy of the antibiotic prophylaxis regimen currently recommended for the prevention of infective endocarditis in periodontitis patients should be discussed. The population at risk of infection are no longer young people with known rheumatic valvular heart disease and are now elderly people with no apparent valve disease. Thus, an extensive systematic review is needed to summarize all the evidence on this question and to assess whether the current restrictions on the use of AP are justified.