Fewer than 2% of patients know which imaging contrast caused their allergic reaction
Fewer than 2% of patients can name the specific contrast imaging agent they are allergic to, according to research published Sunday in Clinical Imaging.
The findings are based on responses from more than 300 adults who suffered an allergic reaction to iodinated intravenous contrast during their CT exam. While previous studies reported up to 70% of such patients can recall their allergies, this study recorded a much lower mark of 1.6%.
Many were able to describe and recall other useful information related to their contrast sensitivities, but Virginia researchers say both patients and providers need to do more.
“Knowing one's allergies is critical for knowing what drugs a patient may be prescribed with probable safety,” Cullen Ruff, with the University of Virginia School of Medicine’s Fairfax Radiological Centers, and colleagues added.
On the provider front, for example, Ruff et al. said the often-used term to describe adverse reactions—“iodine allergy”—is non-specific and “nonsensical.” Ideally, medical records should be as detailed as possible to avoid confusion.
“With the increasing use of electronic medical records, precise documentation in a patient's chart of a specific contrast agent allergy and the specific reaction is strongly recommended, in addition to providing the patient with written documentation, and specification in the radiology report,” the authors added.
The findings are based on questionnaire responses from 307 patients who reported a CT contrast allergy between July and December 2018.
Overall, more than 86% could describe their previous allergic reaction. At the same time, 36.8% remembered the year it occurred, and 40.7% cited the facility or city in which the event took place.
Ruff and co-authors spoke to three of the patients who were able to name their contrast allergy agents to ask how they knew. Each said a technologist or radiologist told them the details and provided the info in writing.
Based on their findings, the authors offered up a few recommendations.
- Providers should tell patients the name of the agent they’re allergic to, and patients should be asked to list that info when detailing their medication allergies.
- Reports should include the specific imaging agent, and adverse reactions should be documented within institutional medical records.
- EMRs should replace “iodine” as an allergy option and instead use dropdown choices, including intravenous contrast agents, povidone soap and shellfish as options.
- Educational outreach can ensure providers document clear information and know the difference between older and more currently used agents.
Read the full study here.
Matt joined Chicago’s TriMed team in 2018 covering all areas of health imaging after two years reporting on the hospital field. He holds a bachelor’s in English from UIC, and enjoys a good cup of coffee and an interesting documentary.