DRESS syndrome due to iodinated contrast media. A case report.

Background: The most frequent non-immediate reactions described with iodinated contrast media (ICM) are mild to moderate, however, some cases of patients with severe non-immediate reactions, such as drug eruption with eosinophilia and systemic symptoms (DRESS) have been described.

Case presentation: An 84-year-old patient developed DRESS syndrome after administration of ICM ioversol. The patient fullfilled the RegiSCAR diagnostic criteria for DRESS (definite score = 6). He underwent intradermal skin testing (IDT) with the widest panel of ICM available at our center. IDT was positive with ioversol and iomeprol. A punch biopsy was performed on the positive IDT with the culprit drug (ioversol) and histopathology was compatible with a T-cell mediated mechanism.

Conclusion: In this case, the IDT-positive biopsy was consistent with DRESS syndrome caused by T-lymphocyte activation, supporting the clinical diagnosis.