Chronic actinic dermatitis. A unifying concept.

Persistent light reactivity, photosensitive eczema, photosensitivity dermatitis, or actinic reticuloid? Increasing experience indicates that these syndromes (Table), which were defined 15 or more years ago and generally occur in elderly men, represent arbitrary, confusing, and largely unnecessary subclassifications, and in this issue of theArchivesLim et al 1 rightly suggest that the conditions should be considered as variants of a single condition, namely chronic actinic dermatitis. The syndrome of persistent light reactivity was first recognized in 1962 by Wilkinson 2 after an epidemic of photoallergy to tetrachlorosalicylanilide, an antibacterial agent incorporated into soaps and hair toiletries. Following an episode of photoallergy caused by epicutaneous contact with a photoallergen such as one of these halogenated salicylanilides, musk ambrette 3 or quinoxaline dioxide, 4 some subjects develop persistent photosensitivity of both exposed and covered skin despite removal of the offending chemical from the environment. Whereas the action spectrum for the initiating