Severe reactions to iodinated contrast agents: is anaphylaxis responsible?

Purpose. The etiology of severe reactions following injection of iodinated contrast agents is the subject of controversy. No consensus has been establ ished regarding the management of patients at risk, risk factors and premed ication because in most cases published no diagnostic exploration has been carried out on patients who have experienced a severe reaction. Material and Methods. Diagnosis of drug anaphylaxis is based on clinical hi story, proof of mediator release and drug-specific IgE antibodies (when the technique is available) or cutaneous tests (when direct technique is not a vailable). Results. This approach has been adopted for etiologic diagnosis of 5 clinic al cases of severe anaphylactoid reactions (including one death) following the injection of ionic and non ionic contrast agents. Clinical symptoms, bi ology and cutaneous tests are consistent with anaphylaxis. Conclusion. Any patient who has had a severe anaphylactoid reaction followi ng injection of a contrast agent should undergo an allergological assessmen t to confirm the diagnosis and identify the culprit contrast agent. Indeed, no premedication has proved efficient for the prevention of subsequent all ergic reactions.