Patch testing with corticosteroid mixes in Europe - A multicentre study ofthe EECDRG

This study investigated whether a corticosteroid mix containing tixocortol pivalate, budesonide, and hydrocortisone-17-butyrate could detect contact a llergy to corticosteroids. 2 corticosteroid mixes, 1 with a high (mix I) an d 1 with a low (mix II) concentration and the 3 individual constituents; ea ch at 2 Concentrations, were inserted into the standard series of 16 partic ipating clinics. Tests were read on day (D) 3 or 4. 5432 patients were test ed, and 110 (2.0%) had positive reactions to at least 1 of the 8 test prepa rations. Of the 8 preparations, mix I identified most allergic patients, fo llowed by mix II, budesonide 0.10%, budesonide 0.002%, and tixocortol pival ate, both concentrations (1.0 and 0.10%) tracing the same number. With the mixes, 53.2-59.6% of tixocortol pivalate allergy was missed. 47 patients we re allergic to either concentration of tixocortol pivalate, 25% of these on ly to 1.0% and another 25% only to 0.10%. Testing with mix I and tixocortol pivalate 0.10% picked up 98/110, testing with tixocortol pivalate 1.0% and 0.10% and budesonide 0.10% picked up 105/110. 3379 patients were read on b oth D3 or D4 as well as on D7. Without a late reading (D7), up to 30% of co ntact allergy to corticosteroid markers was missed.