New British and American guidelines for the antibiotic prophylaxis of infective endocarditis: do the changes make sense? A critical reviewShanson, DavidCurrent Opinion in Infectious Diseases: April 2008 - Volume 21 - Issue 2 - p 191–199 doi: 10.1097/QCO.0b013e3282f94765 Respiratory infections: Edited by Michael S. Niederman Buy Abstract Author InformationAuthors Article MetricsMetrics Purpose of review The British Society for Antimicrobial Chemotherapy and the American Heart Association have radically revised their guidelines for the antibiotic prophylaxis of endocarditis. This review discusses the evidence behind the most controversial changes and considers possible future developments. Recent findings The new guidelines emphasize good oral hygiene for preventing viridans streptococcal endocarditis. Antibiotic prophylaxis for dental procedures is only recommended for patients with the highest-risk cardiac conditions. American Heart Association guidelines no longer recommend prophylaxis for urological and gastrointestinal procedures. Summary While only up to 6% of endocarditis cases may be prevented by antibiotic prophylaxis there is controversy as to what to recommend for the individual cardiac patient undergoing a given procedure. The new guidelines about dental prophylaxis are based on epidemiological studies that failed to include sufficient subjects undergoing specific interventions. When considering viridans streptococcal rather than total bacteraemia rates, asserting that the prevalence of bacteraemia after invasive dental procedures is similar to that after toothbrushing may be incorrect. The British Society for Antimicrobial Chemotherapy report probably overestimates the risk of fatal anaphylaxis after an oral dose of amoxicillin. In contrast, the American Heart Association guidelines comment on the absence of any reports of fatal anaphylaxis associated with the antibiotic prophylaxis of endocarditis. Department of Medical Microbiology, Great Ormond Street Hospital for Children, London, UK Correspondence to David Shanson, Department of Medical Microbiology, Great Ormond Street Hospital for Children, London, WC1N 3JH, UK Tel: +44 (0)20 7405 9200 ext: 7930; e-mail: firstname.lastname@example.org © 2008 Lippincott Williams & Wilkins, Inc.