title: Old but not forgotten: Antibiotic allergies in General Medicine (the AGM Study).
abstract: OBJECTIVE
  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.
  
  
  METHODS
  Multicentre cross-sectional study.
  
  
  METHODS
  All patients admitted to the general medical units of Austin Health and Alfred Health, 18 May - 5 June 2015.
  
  
  METHODS
  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.
authors.affiliation: Austin Health, Melbourne, VIC jason.trubiano@austin.org.au.
authors.forename: Jason A
authors.initials: JA
authors.lastname: Trubiano
authors.affiliation: Austin Health, Melbourne, VIC.
authors.forename: Rekha
authors.initials: R
authors.lastname: Pai Mangalore
authors.affiliation: Monash Medical Centre, Melbourne, VIC.
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Baey
authors.affiliation: Austin Health, Melbourne, VIC.
authors.forename: Duy
authors.initials: D
authors.lastname: Le
authors.affiliation: Alfred Health, Melbourne, VIC.
authors.forename: Linda V
authors.initials: LV
authors.lastname: Graudins
authors.affiliation: Austin Health, Melbourne, VIC.
authors.forename: Patrick G P
authors.initials: PG
authors.lastname: Charles
authors.affiliation: Austin Health, Melbourne, VIC.
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Johnson
authors.affiliation: Alfred Health, Melbourne, VIC.
authors.forename: Ar Kar
authors.initials: AK
authors.lastname: Aung
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000276:immunology*; D003429:Cross Reactions; D004342:Drug Hypersensitivity / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence
chemical_list: D000900:Anti-Bacterial Agents