title: Penicillin skin testing in patients with a history of beta-lactam allergy.
abstract: BACKGROUND
  Vancomycin and fluoroquinolones are commonly used in patients with a history of penicillin allergy.
  
  
  OBJECTIVE
  To determine the safety and utility of penicillin skin testing (PST).
  
  
  METHODS
  Retrospective study of patients with a history of penicillin allergy between April 1, 1999, and September 30, 2004. Penicillin skin testing was performed by means of standard methods using benzylpenicilloyl-polysine, penicillin G, and histamine and saline controls.
  
  
  RESULTS
  Of 596 patients studied, 25.3% were outpatients, 50.3% were inpatients, and 24.3% were intensive care unit patients. The most common antibiotics used during the time of PST were vancomycin and fluoroquinolones. Results of PST were negative in 88.4% of patients, positive in 8.2%, and indeterminate in 3.4%. One patient (0.17%) developed urticaria immediately after PST. Fifty-five percent of patients with negative PST results were changed to a beta-lactam drug, more frequently in the intensive care unit vs the outpatient setting (70.3% vs 8.6%; P < .001) and in adults vs patients younger than 18 years (58.6% vs 8.1%; P < .001). A beta-lactam antibiotic was used in 290 patients with negative PST results. Of the patients given beta-lactam antibiotics, 5 (1.7%) had adverse reactions: 2 had hives after 16 and 20 days of therapy, 1 had a nonspecific rash after 17 days of therapy, 1 had flushing and urticaria 3 hours after a test dose of piperacillin-tazobactam, and 1 had a pruritic rash after 12 hours of therapy.
  
  
  CONCLUSIONS
  Patients with a history of penicillin allergy can safely use beta-lactam drugs if negative PST results.
authors: Department of Pulmonary, Allergy, and Critical Care Medicine, The Cleveland Clinic, Cleveland, Ohio 44195, USA.
authors: Gonzalo Alvarez
authors: GA
authors: del Real
authors: Mark E
authors: ME
authors: Rose
authors: Maria T
authors: MT
authors: Ramirez-Atamoros
authors: Jeffrey
authors: J
authors: Hammel
authors: Steven M
authors: SM
authors: Gordon
authors: Alejandro C
authors: AC
authors: Arroliga
authors: Mercedes E
authors: ME
authors: Arroliga
mesh_terms: D000293:Adolescent; D000328:Adult; D004342:Drug Hypersensitivity; D005260:Female; D006801:Humans; D008297:Male; D008487:Medical History Taking; D010045:Outpatients; D010406:Penicillins / Q000009:adverse effects / Q000276:immunology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012882:Skin Tests / Q000009:adverse effects; D047090:beta-Lactams / Q000009:adverse effects / Q000276:immunology / Q000627:therapeutic use
chemical_list: D010406:Penicillins; D047090:beta-Lactams