Topical treatments in atopic dermatitis may lead to contact dermatitis. This retrospective chart review included children, aged 6-18, with suspected allergic contact dermatitis who had been enrolled in the Thin-layer Rapid Use Epicutaneous Test (T.R.U.E.) trial.
At least one allergen reaction on the T.R.U.E. patch test was noted in:
- 78% of all patients
- 89%% of atopic patients
- 66% of nonatopic patients
Eczema area and severity index scores greater than 10 correlated with a higher probability of more than 3 positive patch tests.
20% of atopic patients showed positive patch tests to Myroxylon pereirae, 19% had reactions to fragrance mix.
The Myroxylon pereirae resin (MP; balsam of Peru) is a natural resin used in the local treatment of burns and wounds. M. pereirae extracts and distillates are often contained in a wide range of cosmetic products. They are frequently implicated in allergic contact dermatitis - to the extent that some dermatoligists considered them an allergy marker to perfumes.
Patch testing is indicated in children with moderate-to-severe atopic dermatitis, given the high rate of contact allergy in the atopic group, especially those with eczema area and severity index scores greater than 10.
Prevention through exposure avoidance to the most frequent contact allergens, especially fragrances in patients with atopic dermatitis, is recommended.
Frequency of contact allergens in pediatric patients with atopic dermatitis. Herro EM, Matiz C, Sullivan K, Hamann C, Jacob SE. J Clin Aesthet Dermatol. 2011 Nov;4(11):39-41.
Sensitivity to Myroxylon pereirae resin (balsam of Peru). A study of 50 cases. Avalos-Peralta P, García-Bravo B, Camacho FM. Contact Dermatitis. 2005 Jun;52(6):304-6.
How to Diagnose Contact Dermatitis?
Topical treatments in atopic dermatitis may lead to contact dermatitis
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