title: Breakthrough reactions of iodinated and gadolinium contrast media after oral steroid premedication protocol.
abstract: BACKGROUND
  Adverse reactions to iodinated and gadolinium contrast media are an important clinical issue. Although some guidelines have proposed oral steroid premedication protocols to prevent adverse reactions, some patients may have reactions to contrast media in spite of premedication (breakthrough reaction; BTR).The purpose of this study was to assess the frequency, type and severity of BTR when following an oral steroid premedication protocol.
  
  
  METHODS
  All iodinated and gadolinium contrast-enhanced radiologic examinations between August 2011 and February 2013 for which the premedication protocol was applied in our institution were assessed for BTRs.
  
  
  RESULTS
  The protocol was applied to a total of 252 examinations (153 patients, ages 15-87 years; 63 males, 90 females). Of these, 152 were for prior acute adverse reactions to contrast media, 85 were for a history of bronchial asthma, and 15 were for other reasons. There were 198 contrast enhanced CTs and 54 contrast enhanced MRIs. There were nine BTR (4.5%) for iodinated contrast media, and only one BTR (1.9%) for gadolinium contrast media: eight were mild and one was moderate. No patient who had a mild index reaction (IR) had a severe BTR.
  
  
  CONCLUSIONS
  Incidence of BTRs when following the premedication protocol was low. This study by no means proves the efficacy of premedication, but provides some support for following a premedication protocol to improve safety of contrast-enhanced examinations when prior adverse reactions are mild, or when there is a history of asthma.
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Gunma University School of Medicine, 3-39-22 Showa, Maebashi, Gunma 371-8511, Japan. akiko_jingu@yahoo.co.jp.
authors.forename: Akiko
authors.initials: A
authors.lastname: Jingu
authors.forename: Junya
authors.initials: J
authors.lastname: Fukuda
authors.forename: Ayako
authors.initials: A
authors.lastname: Taketomi-Takahashi
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Tsushima
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000150:complications / Q000000981:diagnostic imaging; D003287:Contrast Media / Q000008:administration & dosage / Q000009:adverse effects*; D005076:Exanthema / Q000209:etiology*; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000009:adverse effects*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009325:Nausea / Q000209:etiology*; D011292:Premedication / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods; D014581:Urticaria / Q000209:etiology*; D055815:Young Adult
chemical_list: D003287:Contrast Media; D007455:Iodine; D005682:Gadolinium