title: Frequency and Risk Factors of Penicillin and Amoxicillin Allergy in Suspected Patients with Drug Allergy.
abstract: BACKGROUND
  Unconfirmed beta-lactam allergy is a significant public health problem because of the limitations it imposes in drug selection. In this study, we aimed to evaluate patients referred for beta-lactam allergy to determine the frequency of confirmed beta-lactam allergy and identify some risk factors.
  
  
  METHODS
  In a prospective cohort study, all referred patients to Immunology, Asthma and Allergy Research Institute in Tehran University of Medical Sciences (between 2007 - 2009) who suspected to have beta-lactam allergy were entered into this study based on having the inclusion criteria. Follow-up was performed 6 - 8 years after the final diagnosis. Diagnosis of beta-lactam allergy relies on thorough history and specific IgE measurements (ImmunoCAP), skin prick testing (SPT), intradermal testing (IDT), patch testing, and oral drug challenge test.
  
  
  RESULTS
  Fifty-one patients with mean age of 24.5 (±18.5) years were enrolled in this study. Based on workups, beta-lactam allergy was confirmed in 16 (31.4%) patients, suspicious in 22 (43.1%) patients and ruled out in 13 (25.5%) patients.  During the follow-up, 3 patients with suspicious drug allergy consumed the culprit drug with no reaction so allergy was finally ruled out in 16 (31.4%) patients. Age, sex, atopy and family history of drug allergies were not significantly different between the patients with confirmed or ruled-out diagnosis of penicillin and amoxicillin allergy.
  
  
  CONCLUSIONS
  At least up to one-third of patients with a history of beta-lactam allergy are proven to be safe using the drug. Also, a clear protocol consists of serum sIgE assay and SPT can be helpful to the physicians in the health care system.
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Fazlollahi
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Katayoon
authors.initials: K
authors.lastname: Bidad
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Raheleh
authors.initials: R
authors.lastname: Shokouhi
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Raheleh
authors.initials: R
authors.lastname: Dashti
authors.affiliation: Department of Immunology and Allergy, Hazrat Rasoul Hospital, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Nabavi
authors.affiliation: Department of Immunology and Allergy, Children Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Movahedi
authors.affiliation: Department of Immunology and Allergy, Hazrat Rasoul Hospital, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Hasan
authors.initials: MH
authors.lastname: Bemanian
authors.affiliation: Department of Immunology and Allergy, Bahrami Children Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Shafiei
authors.affiliation: Department of Immunology and Allergy, Taleghani Hospital, Gorgan University of Medical Sciences, Gorgan, Iran.
authors.forename: Najmoddin
authors.initials: N
authors.lastname: Kalantari
authors.affiliation: Department of Pharmaceutics, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Effat Sadat
authors.initials: ES
authors.lastname: Farboud
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Pourpak
authors.affiliation: Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Moin
mesh_terms: D000293:Adolescent; D000328:Adult; D000658:Amoxicillin / Q000009:adverse effects*; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D002648:Child; D004342:Drug Hypersensitivity / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007428:Intradermal Tests; D007492:Iran; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D010406:Penicillins / Q000009:adverse effects*; D011446:Prospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D000658:Amoxicillin