Sinițchi Georgeta MD, PhD
Allergy Medical Center Atopia Iasi
Photosensibilization, plants, sun and skin
Author: Georgeta Siniţchi
Photosensitization is an immediate or delayed hypersensitivity reaction (type I and IV immunological reactions after Gell-Coombs classification). The action is initially as a hapten, and then turns into a complete, immunogenic photo-allergen. Ultraviolet rays produce reactions in the presence of a chromophore in the skin. Reactions can be photo-immunological (allergic) but also photo-chemical (photo-toxic). Plants can produce photosensitization, such as “sesquiterpene” lactones. Biological activity is related to the presence of the α-methylene-γ-putirol group. Herbal families containing allergic sesquiterpene lactones are Asteracee, Frunalinacees, Lauracees, Magnoliacees. They are legumes, ornamental or medicinal plants. Skin manifestations can be glans, urticaria, and contact dermatitis in people with repeated contact and hereditary allergic terrain and also professional contacts (agricultural, horticultural). Diagnosis requires anamnesis and careful clinical examination, along with photobiological, phototherapy, patch photo tests, standard photodermatosis kit, histological examinations and specific immunological treatment. In conclusion, the collaboration between the allergologist, the immunologist and dermatologist are required; photodermatosis requires information, knowledge, prevention and specific treatment because the actual incidence is higher than the one communicated.