Commentary: Controversies in NICE guidance on infective endocarditis

Infective endocarditis has always fascinated clinicians, but until 2006 it had rarely caused fisticuffs. In that year, the British Society for Antimicrobial Chemotherapy produced guidelines on the prevention of endocarditis,1 which incensed the British Cardiac Society, apparently causing “dismay among cardiologists and confusion among patients and dentists.”2 The major change was the recommendation to restrict antibiotic prophylaxis to patients judged to be at highest risk. The British Cardiac Society countered by arranging for the National Institute for Health and Clinical Excellence (NICE) to review matters. As a result, NICE has published its own guidelines. Ironically, the draft version received scathing criticism via the British Cardiac Society’s website (www.bcs.com/pages/news_full.asp?NewsID=18369177), and the definitive document seems destined to receive similar flak.

NICE no longer advocates antibiotic prophylaxis for the majority of patients in whom it would previously have been recommended, including those having dental, obstetric, gastrointestinal, and respiratory procedures. This is in clear conflict with long established clinical practice, according to which the devastating consequences of infective endocarditis demand that prophylaxis be given to everyone at any risk.

The full NICE guideline is virtually impenetrable. It is deeply impressive in bringing together evidence from disparate disciplines, but I doubt that any single individual in the UK health community is capable of understanding this vast horizon. I coped with viridans streptococci and Ebstein’s anomaly, but if you also understand Markov subtrees as well as “ACERs” and Weibull functions, then I bow to your Leonardo-like learning, and this new NICE guidance should provide you with some new bedside reading.

The principal recommendations initially appear short and crystal clear. However, although they are explicit in saying what is not recommended, one searches in vain for clarity about what is recommended and how health professionals should provide the “clear and consistent information” that they are expected to offer patients. As all parties acknowledge, it will be hard to explain the shift in policy to patients, who have been reminded for years just how important their antibiotics were. A further substantive shortcoming is the lack of any detail about antibiotic choice or dosage. This will be a particular concern to non-specialists.

A commentator in the BMJ should not sit on the fence, so despite these limitiations, let me say that I will change my practice in line with these guidelines. The recommendations are undoubtedly flawed in not providing positive indications of when to give antibiotics. However, they are clear and based on the most detailed available review of the admittedly imperfect evidence. Antibiotic prophylaxis has never been free nor risk-free, and these financial and health costs have tended to be ignored, not least by cardiologists. I’m swayed by the logic that the twice yearly visit to the dentist must be causing less trouble than twice daily tooth brushing. Antibiotic costs and serious reactions will be hugely reduced, as will the hassle to patients and clinicians. We may fail to prevent small numbers of cases of infective endocarditis, but prevention is in any case currently imperfect.

One final thought: it would be seemly for NICE to suggest that the NHS might adequately compensate anyone whose health suffered as a consequence of the new guidelines. That really would be power with responsibility.