Analysis of cross-reactivity among radiocontrast media in 97 hypersensitivity reactions

Results Ninety-seven patients were included. CR occurred between ionic monomers (IMs) in 2 cases, between non-ionic monomers (NIMs) in 93 cases, between an ionic dimer (ID) and an IM in 1 case, between NIMs and IMs in 38 cases, between NIMs and IDs in 29 cases, between non-ionic dimers (NIDs) and IMs in 9 cases, between IDs in 13 cases, and between NIMs in 65 cases. Multiple correspondence analyses identified two subgroups of RCM in which CR was frequent: Group A (iodixanol, iopamidol, iomeprol, iohexol, ioversol), which share two identical N-(2, 3-dihydroxypropyl) carbamoyl side chains that could be the antigen determinant (also present in other drugs), and Group B (ioxaglate, iobitridol). Conclusion From this largest study of CR between RCM, we demonstrate that frequent CR between RCM does not follow the current chemical classification. Thus, we propose reclassifying RCM, and also suggest re-challenging sensitized patients with RCM from a different CR subgroup than that of the RCM initially involved.