Patch testing to detect corticosteroid allergy: is it adequate?

Whilst patch testing with corticosteroids in ethanol is more sensitive than either petrolatum or the cream formulation, the frequency of false-negative reactions is not known. We have compared patch testing with corticosteroid at 1% in ethanol with intradermal (i.d.) tests using 1 mg corticosteroid suspended in normal saline. Patch tests with tixocortol pivalate and budesonide detected all patients allergic to hydrocortisone and budesonide, respectively. For other corticosteroids, the use of ethanol as a vehicle resulted in both false-positive and false-negative reactions. In particular, patch tests with hydrocortisone-17-butyrate missed 30% of all positive reactions detected by i.d. testing. There may be a case for advising the avoidance of this steroid in all patients who are positive on patch testing to tixocortol pivalate and budesonide.