Joseph M. Baló-Banga, Martina Kádas, Adrienn Kása-Kovács, Adrienne Vajda
Background: The diagnostic evaluation of adverse reactions occurring after iodinated contrast media is still debated. Immediate, delayed-type immune reactions and non-immune adverse events have to be differentiated. Our aim was to assess a safe three-step routine procedure in a single-center teaching hospital 2010-2021 with a prospective “real- life” outlook.
Methods: Forty-seven patients after mild intermediate and severe adverse events were tested in three consecutive days. Skin prick tests with 2 to 5 undiluted media were followed at 24 hours by intradermal testing of 2 different concentrations each (10-2m and 10-3m). The results were red after both 20 and 70 minutes and at 24 hours. On day three one negative medium selected was 1/3 diluted and given intravenously under close observation.
Results: The suspected 32 immediate, 11 delayed hypersensitive and 4 non-immune mediated reactors showed 22.3% skin prick test and 62.7% intradermal test positivity, 11 patients were all negative. The 70 minutes reading of intradermal tests modified the results obtained by 20 minutes. In 44.1% of the cases more and more pronounced positivity was found. The highest response rate was achieved by 10-3m solution of contrast media alone or in combination with 10-2m concentration. The only higher (10-2m) revealed 21.2%, while the only late(24 hours) manifesting tests only 8.1% positivity. Intravenous provocation confirmed in 32/38(84.2%) cases the selected alternative. Six cases were mildly positive. After testing the “real-life” versatility was 85% within the next year.
Conclusion: The three-step workup shown in a single-center based study was proven useful and enabled repeated use of radio contrast media in problem patients.