IgE-mediated adverse reactivity to a radiographic contrast medium

In a patient with a previous history of a serious reaction after intravenous injection of the cholangiographic agent ioglycamic acid (Bilivistan), intravenous cholangiography appeared to be necessary. Therefore intradermal tests were performed in the patient and four controls with three radiographic contrast media closely related in chemical structure. In addition a Prausnitz-Kustner test with heated and unheated patient serum was performed. These tests demonstrated the presence in this patient of selective immediate-type reactivity to ioglycamic acid which was probably IgE mediated. Intravenous cholangiography with iodipamide seemed justified and resulted in no adverse reactions. Although this case may be exceptional, the results suggest that intradermal skin tests at proper concentrations may be useful in choosing the administration of radiographic contrast medium to patients with a history of prior adverse reactions.