Incidence of infective endocarditis on rise in England

James L. Januzzi Jr., MD

When the guidelines changed and the recommendation was made to no longer use antibiotic prophylaxis prior to "dirty" procedures such as dental work, many clinicians were uncomfortable. The busy clinician will tell you that there was a lot of reluctance to let go of pretreatment, given the logical assumption that pretreatment would prevent endocarditis from the bacteremia that follows these procedures. The problem, of course, was that there were no data to suggest that prophylaxis was effective. This was just a circumstance where logic dictated the approach.

The data that were shown from the UK are obviously of great concern. What they showed was that following the National Institute for Health and Care Excellence recommendations in 2008, there was substantial reduction in prescription of antibiotic prophylaxis. Although rates of infective endocarditis were actually rising slowly up to that moment, there was a substantial increased incidence of infective endocarditis. It's obviously a concerning signal. The question is whether that is causal. Is the increase in infective endocarditis in fact related to the 90% reduction in prescription of prophylactic antibiotics or is there something else we are missing?

US guidelines currently state that prophylaxis should be given to patients in particular where infection would be a complicated situation. In other words, patients where treatment of endocarditis would be more complicated or more hazardous, such as patients with complex congenital heart disease, defibrillators or prosthetic heart valves. I would argue that any endocarditis is a complicated situation, so this is an area where a randomized, prospective trial that is well-powered, based on data such as the study from the UK to inform the design of the trial, could really answer.

I have not seen an increased trend of endocarditis in my own practice, but I must admit that I remain concerned. If they are true, these findings may change clinical practice. It is likely that clinicians that had discomfort with suspending prophylaxis may look at these data to justify the prescription in their patients. However, we're dealing with an epidemic of resistant bacteria in part related to indiscriminate antibiotic prescriptions. A study could very well answer the question.

This is a public health issue that should be addressed with a randomized, prospective, controlled trial. It's a study that could easily be done, given equipoise now, where the guidelines have dictated not to give prophylaxis, but the question remains open. It's a study that quite frankly should be done.

N.A. Mark Estes, MD

These data are important and have caused the [United Kingdom] to start to reevaluate [its] recommendations for endocarditis prophylaxis. In the United States, there are published guidelines that we still recommend people adhere to. We are certainly going to look very critically at the analysis that comes out in publication. Several limitations of the data were pointed out by a very thoughtful discussion about indexing the frequency of endocarditis total hospitalizations as well. At this point, the AHA is going to look critically at that data, await the analysis of NICE, but still stick with the current recommendations that exist for endocarditis prophylaxis. This study is insufficient to change current guidelines in the United States.