Antibiotic Prophylaxis

The National Institute for Health and Clinical Excellence (NICE) has issued a clinical guideline (17.03.08) on antibiotic prophylaxis against infective endocarditis (IE).  Click here to see details.

In a significant change to current clinical practice, the guideline recommends that antibiotics to prevent IE should not be given to adults and children with structural cardiac defects at risk of IE who are undergoing dental and a number of non-dental interventional procedures.

IE is an inflammation of the inner lining of the heart, particularly affecting the heart valves, caused by bacterial or other infections. It may arise following bacteraemia in patients who have certain pre-existing heart conditions (see list below). Although IE is a rare condition, with fewer than 10 people in every 100,000 developing it each year, it can be life-threatening. It has been accepted clinical practice to use preventive (prophylactic) antibiotics before dental and some non-dental procedures in people who are considered to be at risk of IE. However, the effectiveness of this treatment in humans has never been properly investigated and clinical practice has been dictated by clinical guidelines based on expert opinion.

The 2008 NICE guideline is based on the best available published evidence and a consensus of multidisciplinary, expert opinion within the Guideline Development Group (GDG). The guideline concludes that there is no consistent association between having an interventional procedure, dental or non-dental, and the development of IE and that the clinical effectiveness of antibiotic prophylaxis is not proven. The evidence also suggests that antibiotic prophylaxis against IE for dental procedures is not cost effective and may lead to a greater number of deaths through fatal anaphylactic reactions than not using preventive antibiotics.

The guideline lists a group of people with particular cardiac conditions as being at risk of developing IE. The conditions listed are;
      • acquired valvular heart disease with stenosis or regurgitation
      • valve replacement
      • structural congenital heart disease, including surgically corrected or palliated structural conditions, but excluding  isolated atrial septal defect, fully repaired ventricular septal defect or fully repaired patent ductus arteriosus, and closure devices that are judged to be endothelialised
      • previous IE
      • hypertrophic cardiomyopathy.

However, the risk assessment accepted by NICE suggests that there is no need to offer antibiotics (to prevent IE) to the group of patients listed above for any of the following procedures:
      • a dental procedure
      • an obstetric or gynaecological procedure, or childbirth
      • a procedure on the bladder or urine system
      • a procedure on the gullet, stomach or intestines
      • a procedure on the airways, including ear, nose and throat and bronchoscopy.

Because patients at risk of IE can be vulnerable in other aspects of their everyday life, dentists and other healthcare professionals can still help by offering people at risk of IE clear and consistent information about prevention, including:
     • an explanation of why antibiotic prophylaxis is no longer routinely recommended
     • the importance of maintaining good oral health
     • symptoms that may indicate IE and when to seek expert advice
     • the risks of undergoing invasive procedures, including non-medical procedures such as body piercing or tattooing.

In addition the guideline mentions the need to investigate and treat promptly any episodes of infection in people at risk of IE to reduce the risk of endocarditis developing.

The guideline has been incorporated in the British National Formulary (BNF) from edition 55 onwards. Members should bear in mind that the BNF is an advisory resource. It is designed as a digest for rapid reference and may not always include all the information necessary for prescribing and dispensing. It should be interpreted in the light of professional knowledge and supplemented as necessary by any future advice from a recognised body of opinion.

Dentists working within an NHS contract are required under the terms of their contract to observe the guidance of NICE when writing prescriptions. Clinicians working privately may not have a contractual obligation to follow this guidance, but they would need a very strong justification for choosing not to do so.

These guidelines may pose a problem for some patients who have been inculcated with the need for antibiotic cover over many years of dental treatment, who under the new guidelines no longer need it. This will need good communication, reassurance and support.

It may be reassuring for patients to know that the Chief Dental Officer has stated, ‘I am delighted that NICE have produced definitive guidance on this complex issue. This will ensure that dentists can give consistent and evidence based advice to their patients. We will work with NICE and other professional bodies to ensure that this advice is disseminated to the profession so that dentists will be in a position to start applying this guidance immediately.’

Dental Protection is not an arbiter of clinical opinion but we recognise that this change will raise concerns both with practitioners and patients. Therefore members are welcome to contact us to discuss any issues arising from the new guideline.

Click here to see a selection of Frequently Asked Questions on antibiotic cover.

Click here to see The Chief Dental Officer's letter on this subject dated 18 March 2008

Revised 11th April 2008