A structured proactive penicillin allergy delabeling intervention in adult patients in three non-university hospitals

Over 90% of patients with penicillin allergy do not have a true penicillin allergy. This allergy label can lead to inappropriate antibiotic prescription, a higher risk of treatment failure and toxicity, and higher rates of infections with multidrug-resistant organisms. Penicillin allergy delabeling strategies are increasingly reported and should be included in antimicrobial stewardship programs. Development and phased implementation of a structured and proactive screening tool and decision algorithm for delabeling presumed penicillin allergy in the preoperative consultations of three non-university hospitals within the same locoregional network. Risk categorization was integrated into a user-friendly screening questionnaire, and streamlined actions were developed through interdisciplinary consensus. The questionnaire was implemented in two pilot phases, with adaptations through feedback from the users and other hospital networks working on penicillin allergy delabeling throughout Flanders. Among a total of 8.659 patients screened, 600 patients (6.93%) reported penicillin allergy, categorized as no risk, low, or high risk of penicillin allergy. 91 patients (15.17%) could be directly delabeled, and 33 patients (5.5%) were delabeled through patient file analysis or further testing. A screening tool for proactive detection of penicillin allergy was developed. This study demonstrates that a substantial proportion of patients with a presumed penicillin allergy can be delabeled non-medically by administering a structured questionnaire, offering a step up towards comprehensive allergologic questioning and patient file analysis, with eventual additional testing in selected patients. The screening tool needs to be validated in a prospective trial including definitive categorization.