The effects on human skin after repetitive ultraviolet-A1 (UVA1) irradiation

Abstract

This chapter discusses topical sensitization and non-oncologic indications related to scleroderma, sarcoidosis, and eczema. Localized scleroderma is characterized by collagen accumulation and excessive sclerosis of the skin. The major complaints are tightness and itching, and the disease is often complicated by contractures and cosmetic disfigurement. Numerous treatments have been tried, such as local corticosteroids, D-penicillamine, intravenous penicillin, intralesional interferon gamma, plasmapheresis, oral psoralen + ultraviolet A (PUVA) therapy or PUVA-bath photochemotherapy, UVA1 phototherapy, and in patients with severe disease immunosuppressive and vasoactive drugs. However, treatments have only limited success or considerable side effects. An advantage of photodynamic therapy (PDT) as compared to PUVA or UVA phototherapy is that carcinogenic effects are not being discussed for PDT. However, prospective, double blind placebo controlled trials with larger number of patients are essential to confirm the value of aminolevulinic acid (ALA)-PDT for the treatment of localised scleroderma. Sarcoidosis is a multi-organ system disease, which is characterized by the formation of non-caseating epithelioid cell tubercles in all or several organs. The lung is by far the most common involved organ in more than 90% of all cases. In contrast, skin involvement occurs only in about 25% of cases, but may be the only manifestation of the disease.