title: The High Impact of Penicillin Allergy Registration in Hospitalized Patients.
abstract: Suspected penicillin allergy (Pen-A) is often not verified or excluded by diagnostic testing.
  
  
  
  To assess the prevalence and impact of Pen-A registration in a Dutch University Medical Center.
  
  
  
  In a prospective matched cohort study, all admitted patients (July 2013-July 2014) who underwent a pharmacotherapeutic interview were selected. Patients with a registered Pen-A were matched on age, sex, and department of admission with up to 3 patients without a registered Pen-A. Relative risks (RRs) of receiving a reserve antibiotic, death during hospitalization, and rehospitalization were compared in the 2 cohorts. The number and type of antibiotics prescribed during admission and duration of hospitalization were compared.
  
  
  
  Of 17,959 patients, 1010 (5.6%) patients (66.7% women; median age, 55 years) had a Pen-A registration. These patients had a higher risk of receiving reserve antibiotics (RR, 1.38; 95% CI, 1.22-1.56) and of being rehospitalized within 12 weeks (RR, 1.28; 95% CI, 1.10-1.49). A significantly larger proportion of Pen-A registered patients received reserve antibiotics such as tetracyclines (1.8% vs 0.8%), macrolides/lincosamides/streptogramins (12.5% vs 4.9%), and quinolones (7.9% vs 4.3%) or received 2 or more types of antibiotics during hospitalization (21.7% vs 16.9%).
  
  
  
  Prevalence of Pen-A registration in hospitalized patients is high, has high impact on antibiotic prescribing, and is associated with a higher risk of readmission. Verification of the Pen-A in hospitalized patients might restrict the use of reserve antibiotics and improve patient outcome.
authors.affiliation: Department of Dermatology and Allergology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Savannah M
authors.initials: SM
authors.lastname: van Dijk
authors.affiliation: Division of Laboratory and Pharmacy, Department of Clinical Pharmacy, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Helga
authors.initials: H
authors.lastname: Gardarsdottir
authors.affiliation: Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Marjan W M
authors.initials: MW
authors.lastname: Wassenberg
authors.affiliation: Department of Internal Medicine and Infectious Diseases, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: Jan Jelrik
authors.initials: JJ
authors.lastname: Oosterheert
authors.affiliation: Division of Laboratory and Pharmacy, Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Mark C H
authors.initials: MC
authors.lastname: de Groot
authors.affiliation: Department of Dermatology and Allergology, University Medical Centre Utrecht, Utrecht, The Netherlands. Electronic address: h.rockmann@umcutrecht.nl.
authors.forename: Heike
authors.initials: H
authors.lastname: Rockmann
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D004342:Drug Hypersensitivity / Q000453:epidemiology*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006785:Hospitals, University / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D010406:Penicillins / Q000009:adverse effects*; D011446:Prospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins
keywords: Allergy registration; Antimicrobial stewardship; Beta-lactam antibiotic; Drug hypersensitivity; Penicillin