In 1975, O'Brien1 described actinic granuloma and indirectly proposed criteria for diagnosis: (1) Annular, slowly enlarging plaques develop on exposed, weather-beaten skin of patients at least 30 or 40 years of age. (2) Elastotic material is present within giant cells, and the inflammation is granulomatous. (3) Elastotic material and elastic fibers are absent from the postreactive central zone and greatly reduced in number and density in the vicinity of giant cells in the annular zone.
Since the naming of this condition by O'Brien, "lumpers" and "splitters" have battled over its uniqueness. Ragaz and Ackerman2 concluded that actinic granuloma was simply granuloma annulare occurring in areas of elastosis. As evidence, they published photographs of a man with widespread papular and annular lesions of granuloma annulare with classic histologic granuloma annulare, who also had large annular lesions on his face and neck clinically typical of actinic
Dahl MV. Is Actinic Granuloma Really Granuloma Annulare?. Arch Dermatol. 1986;122(1):39-40. doi:10.1001/archderm.1986.01660130043020