Actinic granuloma. An annular connective tissue disorder affecting sun- and heat-damaged (elastotic) skin
J. P. O'Brien
Ring-shaped inflammatory lesions sometimes develop in the abnormal
"elastotic" connective tissues of skin damaged by sun and heat. The
lesions, which commence as papules and nodules, enlarge very slowly and may
persist for years. Microscopical sections show that there is an infiltrate
composed mainly of foreign-body giant cells, the cells being engaged in
digesting and absorbing the abnormal elastotic fibers. The disorder, which
occurs on several continents, should probably be regarded as a phenomenon
of repair within damaged connective tissue. The name actinic granuloma
indicates its external or environmental origin and distinguishes it from
other granulomas with which it is constantly being confused. Actinic
granuloma and granuloma annulare appear to be related. In granuloma
annulare, a productive and resorptive process also occurs, but its nature
remains obscure. Actinic granuloma may be misdiagnosed as "atypical
necrobiosis lipoidica" or as a sarcoidosis. The subject of actinic damage
to blood vessels deserves study.
