Despite being a relatively rare event, hypersensitivity reactions to radiocontrast media (RCM) can result in a myriad of complications to patient care affecting access to important diagnostic investigations. Adverse reactions may be classified as allergic or non-allergic. At present there is no structured follow up of these cases. The purpose of this study was to obtain an epidemiological cohort of the allergic mediated RCM reactions and to assess the management practice of such instances including detailed documentation of reactions and referral to an immunology service.

We performed a retrospective review of all documented hypersensitivity reactions to radiocontrast media in the radiology department at St James’s Hospital, Dublin over a ten year period (2008 to 2018). We sub-classified our results into allergy mediated and non-allergy mediated. We recorded the type of contrast agent used, the nature of the reaction as well as the specific action undertaken at the time including patients whom were subsequently referred to an Immunology service for confirmation allergy testing and future risk modification.

Overall, 40 reactions were documented. 80% of these were probable allergic reactions including two cases of anaphylaxis (N=32). Non allergic reactions included seizures, syncope, nausea and burning sensation (N=8). 60% of patients had their reaction documented on either their electronic or physical chart (N=18). Of the 5 inpatients, 80% had their reaction documented on their discharge summary. Patients who underwent outpatient radiological investigations did not receive written documentation specifying their reaction (N=35). In no instance was the specific contrast agent recorded. No patients were referred...

This audit highlights weaknesses in the documentation, communication and investigation of RCM allergy. Documentation of the specific agent is of paramount importance so that lower osmolality agent my be considered in future. Referral of serious reactions to Immunology or Allergy services is important for future risk modification. This can include premedication with corticosteroids or avoidance. A protocolised approach to such cases is being established.

1. Borges, M et al. (2019). Controversies in Drug Allergy: Radiographic Contrast Media. The Journal of Allergy and Clinical Immunology. 7 (1), Pages 61–65. 2. Brockow, K et al. (2016). Drug allergy passport and other documentation for patients with drug hypersensitivity - An ENDA/EAACI Drug Allergy Interest Group Position Paper. Allergy. 71 (11), 1533-1539.

H. Dillon: Nothing to disclose