Allergological risk factors as predictors of radiographic contrast media hypersensitivity.

An in-depth allergy history was obtained from 830 consecutive patients who were subjected to intravenous radiographic contrast medium (RCM) examinations. During the RCM examination 47 patients reacted with symptoms of hypersensitivity. In 26 of these (55.3%) a positive previous allergy history had been obtained. Although this finding was statistically significant, its practical value is severely hampered by the lack of selectivity, many of RCM non-reactors also giving positive allergy histories. A positive history of a previous reaction to RCM or to penicillin, however, was found to have more specificity in predicting a forthcoming hypersensitivity reaction to RCM.