title: Documenting Penicillin Allergy: The Impact of Inconsistency.
abstract: BACKGROUND
  Allergy documentation is frequently inconsistent and incomplete. The impact of this variability on subsequent treatment is not well described.
  
  
  OBJECTIVE
  To determine how allergy documentation affects subsequent antibiotic choice.
  
  
  METHODS
  Retrospective, cohort study.
  
  
  METHODS
  232,616 adult patients seen by 199 primary care providers (PCPs) between January 1, 2009 and January 1, 2014 at an academic medical system.
  
  
  METHODS
  Inter-physician variation in beta-lactam allergy documentation; antibiotic treatment following beta-lactam allergy documentation.
  
  
  RESULTS
  15.6% of patients had a reported beta-lactam allergy. Of those patients, 39.8% had a specific allergen identified and 22.7% had allergic reaction characteristics documented. Variation between PCPs was greater than would be expected by chance (all p<0.001) in the percentage of their patients with a documented beta-lactam allergy (7.9% to 24.8%), identification of a specific allergen (e.g. amoxicillin as opposed to "penicillins") (24.0% to 58.2%) and documentation of the reaction characteristics (5.4% to 51.9%). After beta-lactam allergy documentation, patients were less likely to receive penicillins (Relative Risk [RR] 0.16 [95% Confidence Interval: 0.15-0.17]) and cephalosporins (RR 0.28 [95% CI 0.27-0.30]) and more likely to receive fluoroquinolones (RR 1.5 [95% CI 1.5-1.6]), clindamycin (RR 3.8 [95% CI 3.6-4.0]) and vancomycin (RR 5.0 [95% CI 4.3-5.8]). Among patients with beta-lactam allergy, rechallenge was more likely when a specific allergen was identified (RR 1.6 [95% CI 1.5-1.8]) and when reaction characteristics were documented (RR 2.0 [95% CI 1.8-2.2]).
  
  
  CONCLUSIONS
  Provider documentation of beta-lactam allergy is highly variable, and details of the allergy are infrequently documented. Classification of a patient as beta-lactam allergic and incomplete documentation regarding the details of the allergy lead to beta-lactam avoidance and use of other antimicrobial agents, behaviors that may adversely impact care quality and cost.
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois, United States of America.
authors.forename: Nirav S
authors.initials: NS
authors.lastname: Shah
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois, United States of America.
authors.forename: Jessica P
authors.initials: JP
authors.lastname: Ridgway
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois, United States of America.
authors.forename: Natasha
authors.initials: N
authors.lastname: Pettit
authors.affiliation: Department of Clinical Analytics, Northshore University HealthSystem, Evanston, Illinois, United States of America.
authors.forename: John
authors.initials: J
authors.lastname: Fahrenbach
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois, United States of America.|Department of Clinical Analytics, Northshore University HealthSystem, Evanston, Illinois, United States of America.|Department of Medicine, Northshore University HealthSystem, Evanston, Illinois, United States of America.
authors.forename: Ari
authors.initials: A
authors.lastname: Robicsek
mesh_terms: D004342:Drug Hypersensitivity / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010406:Penicillins / Q000009:adverse effects*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D010406:Penicillins