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.