Imperial College London

Academic Institute

Graham Cooke

Unknown

No

NIBDAPC_2023_0022

Around 6% of the population of the UK has been labelled as having a penicillin allergy. Research has shown, that if you were to do an allergy test in adults with this label, over 95% would turn out to not have an allergy. Research studies in GP practices in the UK and abroad have shown that the penicillin allergy label can have negative impacts. It has been linked with higher rates of resistant bugs which are harder to treat, alongside longer hospital stays. This is because patients with this label are not given penicillin based antibiotics which can be the first line of treatment and the most effective antibiotic for many illnesses. Until recently, testing for penicillin allergy required skin prick testing (a test where a specialist puts a small amount of the substance that someone is allergic to on the skin to see if there is a swelling around that site). These are normally done in specialist allergy clinics. However, recently the British Society of Allergy and Clinical Immunology has provided guidance to doctors in hospital which would allow them to test for penicillin allergy by giving them one dose of oral penicillin, to allow easier and more rapid testing for any allergy. These services are now being set up in various London hospitals to remove penicillin allergy labels. This project would look at data that is already held in the electronic patient notes at Imperial College to see what the impact of penicillin allergy is in West London. We would like to compare records of patients who have a penicillin allergy label against those who do not. We will look at how this affects antibiotic prescribing and compare how many antibiotic resistant bugs there are in each group. This will help us understand what the impact is of a penicillin allergy label.

Antimicrobial resistance (AMR) occurs when bugs such as bacteria become resistant to the drugs used to treat them. This happens when these bugs evolve and develop ways to protect themselves against the drugs that are supposed to kill them. As a result, the antibiotics we use become less effective, and infections become harder to treat. Due to this, AMR is a key policy priority for the UK government and the World Health Organisation (WHO). AMR is estimated to cause 4.95 million deaths worldwide annually and cost the NHS £95 million pounds a year. Penicillins are the first-line antibiotics for many infections because they are often the most effective or less toxic than alternative antibiotics. Patients with a penicillin allergy label are generally not prescribed these antibiotics because of their allergy label. However, 95% of these patients will test negative for the allergy on allergy testing. Penicillin allergy de-labelling (when people without a penicillin allergy are tested and found not to have one, and the label is removed) could be a way to reduce antimicrobial resistance. This is because the alternative antibiotic groups (e.g. lincosamides and quinolones), which are used instead of penicillins, have been shown to cause higher rates of diseases such as C. difficile and MRSA infection, which are due to antibiotic overuse. This will not only benefit individual patients but society as a whole. If patients are de-labelled from having a penicillin allergy, they will have access to penicillins and the group of antibiotics they belong to, called "beta-lactams," which may be less toxic and/or the first-line treatment choice for many infections. This can improve mortality in certain infections, such as Staphylococcus aureus bacteraemia (a type of infection in the blood), where penicillin-type antibiotics (beta-lactams) have been shown to be more effective than non-beta-lactam antibiotics. Under new British Society of Allergy and Clinical Immunology guidance, doctors who are non-allergists can perform de-labelling within hospitals, removing the need for an outpatient appointment, which can take a long time and is partly the reason why patients have not been de-labelled in the past. This project was identified as there are plans in many London hospitals to set up penicillin de-labelling services. We would like to investigate the impact of the penicillin allergy label on antimicrobial resistance in London to see how effective these services may be. Additionally, we may gain insight into which patients should be targeted for penicillin allergy testing within hospitals to have the most impact of de-labelling on antimicrobial resistance.

Public Health Research

18/12/2023

31/03/2023

De-Personalised

Not applicable

Not applicable

One-off

18/12/2023

TRE