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Minimal Erythema Dose (MED) Testing
Published on: May 28, 2013
Repeat contrast medium reactions in premedicated patients: frequency and severity
Matthew S Davenport1, Richard H Cohan, Elaine M Caoili
1Department of Radiology, University of Michigan Medical Center and Health System, 1500 E Medical Center Dr, UH B1-D502, Ann Arbor, MI 48109-5030, USA. matdaven@med.umich.edu
Radiology
|October 1, 2009
Summary
Breakthrough reactions to iodinated low-osmolality contrast medium (LOCM) are typically similar in severity to the initial reaction. Repeat reactions are uncommon, but certain risk factors increase the likelihood of moderate or severe breakthrough reactions.
Area of Science:
- Radiology
- Allergy and Immunology
- Pharmacology
Background:
- Contrast-enhanced medical imaging frequently utilizes iodinated low-osmolality contrast medium (LOCM).
- Patients with a history of contrast medium reactions may experience breakthrough reactions despite premedication.
- Understanding breakthrough and repeat reactions is crucial for patient safety.
Purpose of the Study:
- To determine the frequency, type, and severity of breakthrough and repeat breakthrough reactions to LOCM.
- To identify risk factors associated with moderate or severe breakthrough reactions.
- To evaluate the impact of premedication on reaction outcomes.
Main Methods:
- Retrospective analysis of 190 breakthrough allergic-like reactions to intravenous LOCM in 175 patients.
- Review of 197 repeat breakthrough reactions in 58 patients following initial reactions.
- Fisher exact test and subgroup analysis to assess risk factors and reaction severity.
Main Results:
- 81% of breakthrough reactions were similar in severity to the index reaction.
- 91% of breakthrough reactions were mild when the index reaction was mild.
- 88% of subsequent LOCM injections did not result in repeat breakthrough reactions.
- Chronic corticosteroid use, drug allergies, or multiple allergies increased the risk of moderate/severe reactions.
Conclusions:
- Breakthrough reactions to LOCM are generally similar in severity to the initial reaction.
- Subsequent LOCM injections rarely induce repeat breakthrough reactions.
- Specific patient risk factors are associated with more severe breakthrough reactions.
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