Delayed Adverse Reaction to Contrast-enhanced CT: A Prospective Single-Center Study Comparison to Control Group without Enhancement

Abstract
We found that patients who received a monomeric contrast agent had a significantly higher incidence of delayed adverse reactions than those who did not receive contrast material. PurposeTo prospectively assess the incidence of delayed adverse reactions (DARs) in patients undergoing contrast material–enhanced computed tomography (CT) with the low osmolar nonionic contrast agent iohexol and compare with the incidence of DARs in patients undergoing unenhanced CT as control subjects.Materials and MethodsInstitutional review board approval and informed written consent for this prospective study were obtained. The study was HIPAA compliant. Patients undergoing CT for routine indications were enrolled from a random next-available scheduling template by an on-site clinical trials monitor. All subjects received a questionnaire asking them to indicate any DAR occurring later than 1 hour after their examination. Sixteen manifestations were listed and included rash, skin redness, skin swelling, nausea, vomiting, and dizziness, among others. To ensure maximal surveillance, a clinical trials coordinator initiated direct telephone contact for further assessment. Patients suspected of having mode...