New BSACI guideline on penicillin allergy de-labelling

The British Society for Allergy and Clinical Immunology (BSACI) has published a new guideline for the evaluation and testing of patients with an unsubstantiated label of penicillin allergy.

More than 10% of the elective surgical population carries a label of penicillin allergy. These labels are associated with significant harms, including increased surgical site infections, MRSA and C. difficile infections, and longer hospital stays. While many of these harms are downstream of the surgical episode itself, there is also an immediate risk from teicoplanin anaphylaxis during surgery, when this is used as a second line agent.

At least 95% of penicillin allergy labels are incorrect. However, these labels persist for life and patients rarely have the opportunity to have them tested and removed, a process known as ‘de-labelling’. There are very few allergists in the UK and access to allergy services is therefore very restricted.

The pre-operative setting is ideal for de-labelling, as it leads directly to better antimicrobial stewardship during the planned surgery and beyond. The new BSACI guideline sets out the process by which suitable patients can be de-labelled by non-allergists, including anaesthetists, using an oral challenge test to penicillin. This is a quick, simple and effective test that provides definitive evidence that a patient can tolerate penicillin. The key feature of the pathway is in the risk stratification of patient’s allergic history, so that only those at low risk of true allergy undergo challenge testing. Studies around the world have shown that challenge testing in low-risk patients is very safe. The guideline states that de-labelling pathways must be set up with the direct oversight of local or regional allergy services and that these services need to retain an advisory role for the non-allergist delivering the testing.

The guideline recommends that de-labelling should become part of routine optimisation of patients waiting for surgery. It has been endorsed by the Royal College of Anaesthetists, the Association of Anaesthetists, the Royal College of Physicians, the Royal College of Pathologists, the British Society of Allergists and Clinical Immunologists and others. The guideline can be freely accessed online.