Question

• In people at increased risk of bacterial endocarditis, is antibiotic prophylaxis before an invasive dental procedure effective in preventing endocarditis?

Clinical Bottom Lines

1. There is no evidence that antibiotic prophylaxis is effective or ineffective at preventing bacterial endocarditis in patients at risk undergoing an invasive dental procedure.¹
2. Physicians need to discuss the potential harms and benefits of antibiotic prophylaxis with their patients before prescribing their use.

Summary of Key Evidence

1. A systematic review was conducted in 2004 to determine whether prophylactic antibiotic administration before invasive dental procedures in patients at increased risk of bacterial endocarditis is effective.¹
2. 908 references were identified through a literature search. After assessment of titles and abstracts by two reviewers, 108 references remained. After review of full texts, 107 were excluded, leaving one case control study.
3. Odds ratio for developing endocarditis with penicillin prophylaxis compared to no prophylaxis was 1.62 with 95% confidence interval of 0.57 to 4.57.

Additional Comments

• Physicians feel obligated to follow guidelines despite the lack of evidence that antibiotic prophylaxis is effective.
• Because the incidence of endocarditis is so low, a RCT done over 2 years would require inclusion of 60,000 patients with a cardiac risk factor for endocarditis.
• The American Heart Association has published guidelines recommending the use of prophylactic antibiotics when undergoing surgical or dental procedures likely to cause bacteremia in those cardiac conditions associated with endocarditis.
  

Citation

1. Oliver, R; Roberts, GJ; Hooper, L. Penicillins for the prophylaxis of bacterial endocarditis in dentistry. The Cochrane Database of Systematic Reviews 2005; 1.

CAT Author: Kathryn Nardell, MD

CAT Appraisers: Alex Kemper, MD

Date appraised: May 11, 2005