Chronic actinic dermatitis. Study of the spectrum of chronic photosensitivity in 12 patients.

Twelve patients with photodermatitis for longer than 3 months' duration were identified: 1 patient with chronic photocontact dermatitis, 1 with persistent photosensitivity following exposure to a systemic medication, 6 with persistent light reactivity, and 4 with actinic reticuloid. There were 10 men and 2 women, ranging in age from 27 to 81 years, with a mean age of 62 years. The duration of the eruption ranged from 6 months to 20 years. Persistence of photosensitivity to quinidine, which is analogous to persistent light reactivity, was documented in 1 patient, and evolution from photocontact dermatitis to actinic reticuloid was observed in 2 others. These data, along with those reported in the literature, indicate that chronic photocontact dermatitis, persistent photosensitivity to systemic agents, persistent light reactivity, photosensitive eczema, and actinic reticuloid should be considered as entities occurring along a continuum, and the term "chronic actinic dermatitis" is suggested to refer to these entities. Eight (67%) of the 12 patients had skin type VI and 2 others (17%) had skin type V, percentages markedly higher than those of the general patient population, demonstrating that chronic actinic dermatitis is not uncommon among individuals with dark skin.