Real incidence and management of patients with suspected iodinated contrast media allergy in our area

Adverse reactions to iodinated contrast media (ICM) are very common due to its widespread use. Despite the fact that overall incidence of hypersensitivity reactions (HSRs) to ICM is low, the risk of severe outcomes needs a careful patient evaluation and management. We conducted a retrospective epidemiological study that included patients referred to our Allergy Unit for suspected allergy to ICM in whom we carried out a protocolized allergic study based on skin and drug provocation tests (DPT). A total of 108 patients were tested and allergy to ICM was confirmed in 29 (26.9%) and assumed in 9 (8.3%). All these patients tolerated DPT with alternative ICM. The most frequently involved contrasts in confirmed HSR were iodixanol and iohexol, and iopromida was the best tolerated. Out of a total of 125 DPT, we obtained 26 positive results with only two systemic reactions (mild). In most of the patients in our sample, allergy to ICM was ruled out, and in allergic patients, tolerance to an alternative ICM was established. Our protocol is safe and allows patients to receive ICM in the future.