Excited skin syndrome (ESS) is an adverse reaction obtained when carrying out epicutaneous patch tests, characterized by multiple positive test results, associated with one or more strongly positive tests, which are not all reproduced when the patient is tested afterward.
The aim of this study was (1) to determine the frequency of ESS in patients submitted to patch testing, (2) to confirm the influence of the evolution time of the primary dermatosis with ESS induction, (3) to determine differences among patients according the rate of positive test loss, and (4) to compare the number of positive tests for each substance between the first test, when all allergens in the test battery were applied, and the second test, when only the allergens with positive tests on the first occasion were applied at a greater distance from one another.
Epicutaneous tests were carried out in 630 patients with a suspected diagnosis of allergic contact dermatitis. Patients presenting 2 or more positive test results were considered to have ESS and were submitted to a second patch test.
Results and Conclusions:
ESS developed in 39 of the 630 patients tested, corresponding to a frequency of 6.2%. Analysis of data found a longer duration of the primary dermatitis in patients who in whom ESS developed compared with those who did not. Parabens, fragrance mix, and thimerosal had more positive patch test reactions using standard application techniques relative to the retest procedure, which placed the substances at a greater distance from one another, suggesting that, in addition to the factors previously reported to influence the reduction of ESS, the position of the allergens in the testing procedure also should be considered.