Objectives: To determine the nature, prevalence and description accuracy of recorded antibiotic allergy labels (AALs) in a cohort of general medical inpatients, and to assess the feasibility of an oral antibiotic re-challenge study.Design: Multicentre cross-sectional study.Setting and participants: All patients admitted to the general medical units of Austin Health and Alfred Health, 18 May – 5 June 2015.Main outcome measures: Baseline demographics, medical and allergy history, infection diagnoses and antibiotic prescribing data for general medical inpatients were collected. A questionnaire was administered to clarify AAL history, followed by correlation of responses with electronic and admissions record descriptions. A hypothetical oral re-challenge in a supervised setting was offered to patients with low risk allergy phenotypes (non-immediate reaction, non-severe cutaneous adverse reaction, or unknown reaction more than 10 years ago).Results: Of the 453 inpatients, 107 (24%) had an AAL (median age, 82 years; interquartile range, 74–87 years); 160 individual AALs were recorded, and there was a mismatch in AAL description between recording platforms in 25% of cases. Most patients with an AAL were women (64%; P < 0.001), and more presented with concurrent immunosuppression than those without an AAL (23% v 8%; P < 0.001). β-Lactam penicillins were employed less frequently in patients with an AAL (16% v 35%; P = 0.02), while ceftriaxone (32% v 20%; P = 0.02) and fluoroquinolones (6% v 2%; P = 0.04) were used more often. Fifty-four per cent of patients with AALs were willing to undergo oral re-challenge, of whom 48% had a low risk allergy phenotype.Conclusions: AAL prevalence in general medical inpatients was 24%, and was associated with excessive use of broad spectrum antibiotics. Allergies in a large proportion of patients with AALs were incorrectly documented, and were non-immune-mediated and potentially amenable to oral re-challenge. A direct oral re-challenge study in carefully selected patients with low risk allergy phenotypes appears feasible.
Trubiano, J. A., Pai Mangalore, R., Baey, Y. W., Graudins, L. V., Charles, P. GP., Johnson, D. F., & Aung, A. K. (2016). Old but not forgotten: Antibiotic allergies in General Medicine (the AGM Study). The Medical Journal of Australia, 204(7), . https://doi.org/10.5694/mja15.01329