(HealthDay) -- More than 50 percent of patients with nonimmediate reactions to iodinated contrast media (CM) are identified with the drug provocation test (DPT) and not with skin testing, according to a study published online May 15 in Allergy.
Maria J. Torres, M.D., Ph.D., of Carlos Haya Hospital in Malaga, Spain, and associates investigated the role of skin testing and the DPT in the diagnosis of nonimmediate reactions to CM in 161 patients. Skin intradermal and patch testing were performed with different CM. In cases with a negative skin test, a single-blind placebo-controlled DPT was performed.
The researchers found that 21.1 percent of the subjects were skin-test positive to the various CM. In 34.6 percent of skin-test negative cases the DPT was positive. Of the 78 cases with confirmed hypersensitivity, 56.4 percent were identified by DPT and 43.6 percent were identified by skin testing.
"We conclude that skin-test sensitivity is not sufficient and that, in more than 50 percent of cases, a DPT is also needed to establish the diagnosis," the authors write.
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