Melbourne researchers have led the world's largest study confirming most patients labelled allergic to penicillin are not truly allergic.
The study, described as a "game changer" by lead author Professor Jason Trubiano, demonstrates for the first time that penicillin allergy testing can be safely delivered at scale as part of routine hospital care worldwide.
Professor Trubiano is head of Infectious Diseases at the University of Melbourne, based at the Peter Doherty Institute for Infection and Immunity. Published today in Clinical Infectious Diseases, the international study involved more than 5,000 patients across 40 hospitals in Australia, the United Kingdom, the United States, Canada, Malaysia, South Africa, Hong Kong and New Zealand.
Professor Jason Trubiano has led a new global study to help de-label people with a low-risk penicillin allergy.
Around one in ten hospital patients are recorded as having an allergy to penicillin, limiting their options for antibiotic treatments.
Of the 1,573 patients who received a supervised test dose of penicillin as part of the study, 95 percent were safely confirmed not to be allergic and had their medical records corrected, enabling clinicians to prescribe more effective first-line antibiotics and reduce delays in treatment.
Professor Trubiano, also the Director of Infectious Diseases and Immunology at Austin Health and an infectious diseases physician, said incorrect penicillin allergy labels were a significant global healthcare challenge and these findings marked a critical shift from specialist research into global clinical practice.
"Around 10 per cent of hospitalised patients globally report a penicillin allergy, however most are not truly allergic, often because they were misdiagnosed in childhood, outgrew it or it's been years since their last reaction," Professor Trubiano said.
"Misdiagnosis can result in inappropriate antibiotic prescribing, longer hospital stays, increased healthcare costs and more readmissions.
"Our previous studies showed penicillin allergy testing could be done safely in smaller patient groups and specialist settings. This global study is a game-changer.
A nurse preparing drugs that are used for penicillin allergy skin testing. The new study shows a single oral test dose would replace the need for this kind of testing.
"For the first time, we have shown this approach can be safely implemented at scale across entire hospital systems, using technology to support clinicians and allowing hospitals worldwide to deliver this testing as part of routine care. For patients, that means faster access to the most effective antibiotics and better treatment outcomes."
A key innovation trialled in this study was the use of a purpose-built smartphone assessment tool enabling doctors, pharmacists and nurses to identify low-risk patients and safely administer a supervised test dose of penicillin during routine hospital care, including in hospitals without specialist allergy services.
University of Melbourne PhD candidate and Austin Health Drug Allergy Pharmacist Elise Mitri said the findings demonstrated the model could now be safely implemented at scale.
"This study shows penicillin allergy testing can be safely integrated into everyday hospital care, ensuring patients receive the most appropriate and effective treatment.
"The model is already being rolled out in hospitals across Australia and internationally."
Following the adult study, the model will be expanded to children at six hospitals across Australia in partnership with the National Allergy Centre of Excellence (NACE), hosted at the Murdoch Children's Research Institute (MCRI).
Professor Kirsten Perrett, Director of the NACE and MCRI Population Allergy Group Leader, said about 5 per cent of hospitalised children report a penicillin allergy and the rate only increased with age.
"The new study will help assess hundreds of children with a reported penicillin, cephalosporin or sulfonamide allergy," she said.
