We aimed to determine the prevalence of Antibiotic Allergy (AA) labels in a cohort of general medical inpatients and to describe the nature of AA, accuracy of recording and feasibility of an oral re-challenge study.
Multi centre, prospective non-interventional study conducted at Austin Health and Alfred Health, from May 18th to June 5th, 2015. Baseline demographics, medical and allergy history, infective diagnosis and antimicrobial prescribing data was collected from admission and electronic medical records of all general medical inpatients. A survey to clarify allergy history was undertaken for patients with AA, followed by correlation with description in electronic and admission record. A hypothetical oral re-challenge in a supervised setting was offered to patients with a low risk allergy phenotype (uncomplicated rash or non-immune mediate adverse reaction).
Of the 453 inpatients, 23.62% had an AA label. Of these patients 162 allergy labels were recorded, 34% were for penicillin and 21% had a mis-match in documentation between electronic and medical record. 37% of the AA labels were for ‘rash’ or non-immune mediated reactions. 32% of AA labels were unknown reactions and 36% occurred > 10 years previously. Fifty-four percent of AA patients were willing to be re-challenged, 31% exhibiting a low risk allergy phenotype.
AA prevalence in general medical inpatients was 23.62%, 34% of antibiotic allergy labels toward penicillin. A large proportion of AA labels were non-immediate reactions, many of which were potentially amenable to re-challenge. A direct oral antibiotic re-challenge study in carefully selected low risk allergy phenotypes may be feasible.