Last Updated: 2023-07-07
Author(s): Anzengruber F., Navarini A.
In people with specific sensitisation to a certain allergen, dermatitis develops after contact sensitisation in the case of re-exposure.
As with other contact allergies, sensitisation is necessary first. With renewed exposure and UV-A radiation (less or rarely UV-B), photoallergic dermatitis develops.
Sharp, erythematous papules and papulovesicles. In some cases, blisters may also appear if the reaction is severe. A chronic photoallergic contact eczema may develop if the reaction persists.
- Photopatch test
Parahyperkeratosis, acanthosis, spongiosis, perivascular infiltrate.
Contact allergy lasts a lifetime. However, after eliminating the photoallergen, exacerbation can be prevented.
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- Mowad CM, Anderson B, Scheinman P, Pootongkam S, Nedorost S, Brod B. Allergic contact dermatitis: Patient management and education. J Am Acad Dermatol. 2016 Jun;74(6):1043-54.