Introduction of a Penicillin Allergy De-Labelling Program with Direct Oral Challenge is Associated with Increased Downstream Utilization of Beta-Lactam Antimicrobials: A Multicenter Parallel Cohort Study with Crossover Evaluation

BackgroundPenicillin allergy labels are common and are often inaccurate. These labels can lead to unnecessary use of second-line non-beta-lactam antibiotics, and worse clinical outcomes. ObjectivesWe measured the impact of the introducing of a standardized proactive penicillin allergy de-labelling program with oral amoxicillin challenge on subsequent antibiotic use. MethodsWe performed a retrospective comparison of parallel cohorts from two separate tertiary care hospital campuses across two penicillin de-labelling intervention periods. Outcomes included data including penicillin allergy label and antibiotic use, were collected for the index admission and the subsequent 6-month period. Descriptive statistics as well as multivariate regression analyses were performed. ResultsA total of 368 patients with penicillin allergy label were included across two campuses and study periods. 24 (13.8%) patients in the intervention group sustained penicillin allergy label at 30 days from admission vs. 3 (1.5%) in the non-intervention group (p < 0.001). In the 6-months following admission, beta-lactams were prescribed more frequently in the intervention groups vs. the non-intervention groups for all patients (28 [16.1%] vs 15 [7.7%], p= 0.04) and for only those patients who received antibiotics (28/46 [60.9%] vs. 15/40 [37.5%], p=0.097). In a multivariate analysis, the intervention was found to be associated with an increased odds of beta-lactam prescribing in all patients (OR 2.49, 95% CU 1.29-5.02) and in those prescribed at least one antibiotic (OR 2.44, 95% CI 1.00-6.15). There were no differences in overall antibiotic prescribing by intervention and non-intervention group during admission (113 [64.9%] vs. 112 [57.7%]) or within 6-months (46 [26.4%] vs. 40 [20.6%]). No drug related adverse events were reported. ConclusionsProactive penicillin allergy de-labelling for inpatients was associated with a reduced number of penicillin allergy labels and increased utilization of beta-lactam vs. other antibiotics in the subsequent 6-months. Capsule SummaryA proactive systematic approach to antibiotic allergy de-labelling for inpatients with penicillin allergy label results in an increased number of patients de-labelled at hospital discharge and increased beta-lactam use in the subsequent 6 months.