Patch testing in Iranian children with allergic contact dermatitis.

Background: Allergic contact dermatitis is a common disorder in adults and children alike and appears to be on the increase. The purpose of this study was to determine the sensitization trends in Iranian children with contact dermatitis.

Methods: The result of 109 patch tests performed using the 24 allergens of the European Standard Series in patients below 18 years old from September 2007 to March 2009 were recorded and analyzed. The tests were evaluated at 48 and 72 h after performing.

Results: The study population consisted of 72 (66.1 %) females and 37 (33.9 %) males. Hands were the most commonly affected anatomic site. In the final evaluation of the tests on day three, 51 (46.8 %) individuals showed a positive reaction to at least one allergen. Females were significantly more likely to show a positive response to at least one allergen (p-value = 0.031, odds ratio: 2.46). The most common allergens were nickel sulfate, cobalt, methylisothiazolinone, and colophony with 21 (19.3 %), 11 (10.1 %), 7 (6.4 %), and 6 (5.5 %) positive reactions, respectively. Contact allergy to nickel sulfate was more common in females than males (23.6 % vs. 10.8 %). There was no statistically significant relationship between personal or family history of atopy and a positive reaction to patch testing. The clinical and practical relevance were assessed for nickel and cobalt with a clinical current relevance in 11 (52.3 %) and 4 (36.4 %), respectively.

Conclusions: Nickel sulfate, cobalt, methylisothiazolinone, and colophony are the most common allergens responsible for induction of allergic contact dermatitis in Iranian children and adolescents. Females tended to show more positive reactions to allergens.