Cross-reactivity among iodinated contrast agents: should we be concerned?

Background: Although several papers deal with cross-reactivity in patients with iodinated contrast medium (ICM) hypersensitivity reactions (HSRs), there is no in-depth knowledge of this phenomenon. To define ICM-groups as potential reaction partners and to identify any potential clinical relevance in patients with ICM-HSRs. Methods: The literature database PubMed was searched for eligible papers dealing with ICM-allergy and cross-reactivity. The data presented by the papers was analyzed and individual patient data was extracted for re-evaluation based on a definition for both 'polyvalent reactivity' and 'cross-reactivity' as well as for chemical structure-dependent ICM-groups. Results: Twenty-five original papers (with n=340 extracted patients) formed the study population. Incidences of polyvalent reactivity were non-significantly higher than incidences of cross-reactivity (both range from 0% to 100%). Crossover evaluation in reaction pairings (culprit ICM A with ICM B versus culprit ICM B with ICM A) showed concordance of only 30%. Data support rather non-cross-reactivity (individual reaction pattern) than cross-reactivity constellations. Conclusions: The obtained results favour an individual reaction pattern, rather than a reactivity driven by chemical structures and so-called cross-reactivity.

Automated summary

This study on cross-reactivity in patients with ICM hypersensitivity reactions found that incidences of polyvalent reactivity were similar to incidences of cross-reactivity, but there was only 30% concordance in reaction pairings. The data suggest individual reaction patterns rather than cross-reactivity constellations.