Should patients with risk factors be tested for hypersensitivity to contrast media: a prospective study.

Abstract

Previous hypersensitivity reactions to contrast media (CM), atopy, atopic disease, drug allergy, and age (20-29 or>55) are risk factors for CM hypersensitivity reactions. Our aim was to evaluate whether these risk factors should prompt skin testing for diagnosing CM allergy. The study was conducted among patients referred for allergy testing with CM. Skin tests were performed with non ionic or gadolinium CM, recommended by a radiologist. After completion of tests patients were telephonically queried on their symptoms of reactions. 151 risk patients (53 men, 98 women; mean age 55.2) were included in the study. Only 13 (9%) had a history of hypersensitivity reaction to CM. Compared with the other patients, atopy was significantly more common in patients with a history of CM hypersensitivity reactions. Female gender and mean age were also higher, but not significant. All of the tests with CMs were negative. Only one patient reported urticaria within 1-2min after administration of CM (telephonically). Atopy can increase the risk of CM allergy. However, skin tests with CMs may be inefficient, unnecessary, and time-consuming, except in cases with a history of CM allergy. Premedication protocols appear to be beneficial in patients with a history of CM allergy and cannot be recommended for patients with well-controlled asthma, rhinitis, atopic dermatitis or history of drug allergy.