Chronic actinic dermatitis. An analysis of 51 patients evaluated in the United States and Japan.

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.