Secondary localized cutaneous amyloidosis in solar elastosis.

A case of secondary localized cutaneous amyloidosis in solar elastosis was studies by light and electron microscopy. Amyloid deposition was restricted to areas with elastotic changes, and in some areas both changes were intermingled with each other. The amyloid was permanganate-sensitive, and proved to be protein AA. Ultrastructurally it was composed of fine tubular filaments. It is suggested that the amyloid deposition in this case was related to sunlight damage of the skin.