Photodermatitis

Abstract: Drug-induced photosensitivity involves reactions to medication triggered by exposure of the skin to ultraviolet light. Medications that trigger reactions can be topical or oral. Following interaction of ultraviolet radiation with a chemical present in sufficient amounts in the skin, one of the several reactions may occur in susceptible patients, most commonly photoallergy or phototoxicity. These reactions can be diagnosed separately based on pathogenesis, clinical characteristics and histopathology. Phototoxic disorders have a higher incidence than photoallergic disorders. The action spectra for most photoallergens and phototoxins lie in the ultraviolet A range. Subtypes of drug-induced photosensitivity include dyschromia, pseudoporphyria, photo onycholysis, and lichenoid and telangiectatic reactions.

Abstract: Infectious diseases ectoparasites hypersensitivity immune mediated dermatoses keratinisation disorders pigment disorders disease of the ear cutaneous manifestations of internal disease photodermatitis dermatoses of unknown cause.

Abstract: Background and Design: We studied the clinical and photobiologic features of 51 patients with chronic actinic dermatitis who were evaluated at three institutions. The following criteria for patient selection were used: (1) a persistent eczematous eruption in the sun-exposed areas of greater than 3 months' duration; (2) decreased phototest results; and (3) when available, histologic changes of a dermal infiltrate of lymphocytes and macrophages, with or without epidermal spongiosis and atypical mononuclear cells in the dermis and epidermis. Results: The 51 patients had a mean age of 62.7 years, a male-to-female ratio of 2.6:1, and a mean duration of eruption of 5.8 years. The most common abnormal results of the phototests were decreased minimal erythema doses to both UV-A and UV-B, followed by decreased minimal erythema doses to UV-A alone. Patients with abnormally low responses to UV-A or visible light and normal minimal erythema doses to UV-B had the same clinical profile as the overall patient population. Aside from protection from sunlight, treatment modalities that have been used include PUVA (8-methoxypsoralen and UV-A) photochemotherapy, azathioprine, hydroxychloroquine sulfate, and, for recalcitrant cases, cyclosporine. Conclusions: Chronic actinic dermatitis is a persistent photodermatosis associated with abnormal phototest responses to UV-A, and/or UV-B, and/or increased sensitivity to visible light; histopathologic changes are consistent with photodermatitis. Treatment consists of combinations of topical and oral medications. (Arch Dermatol. 1994;130:1284-1289)

Abstract: Background: Photoallergic contact dermatitis from topical ketoprofen (KP), a nonsteroidal anti-inflammatory agent, is a well-known side effect. Objectives: To investigate photo-contact allergic reactions to KP and other nonsteroidal anti-inflammatory drugs (NSAIDs), sunscreens, and fragrance components as well as the presence of prolonged photosensitivity related to it. Patients/Methods: From June 1993 to June 2007, 42 patients were patch tested and photopatch tested with the ingredients of a KP preparation and other relevant substances. A questionnaire was performed in order to determine the importance of prolonged photosensitivity; 40/42 did respond. Results: 38 patients showed photo-contact reaction, 1 photoaggravated reaction, and 3 contact allergic (CA) reaction to KP. Simultaneous photo-contact allergic reactions were frequently observed not only to structurally related but also to non-structurally related NSAIDs and sunscreens. Simultaneous CA to fragrance components was common. 1/3 of the patients reported prolonged photosensitivity, i.e. from 1 up to 14 years after having stopped KP application. Conclusions: The history is often not a good guidance to determine KP-related (photo) allergic contact dermatitis and the severe clinical symptoms sometimes require hospitalization, and/or systemic corticosteroids. As for the association between KP and sunscreen intolerance (being 1 of the possible causal factors for recurrent dermatitis), routine standard photopatch testing with KP might be indicated.