Unusual skin manifestation of cutaneous amyloidosis.

A 76-year-old man with a 20-year history of extensive cutaneous amyloidosis is reported. He had asymptomatic symmetric brownish reticulated pigmented patches with well-demarcated borders on his thighs, lower legs, dorsal feet and both arms. The trunk and popliteal fossae were not affected. A skin biopsy specimen showed abundant amyloid deposits in the papillary dermis and reticular dermis. Despite the extensive cutaneous involvement and large amount of amyloid in the deep dermis, no evidence of systemic amyloidosis could be found. Various manifestations of cutaneous amyloidosis are reviewed. We report this case to remind dermatologists of the protean presentations of cutaneous amyloidosis.