History:

This elderly man developed an intensely pruritic bilateral eruption over the pretibial regions comprised of multiple skin colored to brown hyperkeratotic papules coalesed into large plaques.

Lichen amyloidosis, first described by Gutmann in 1928, is a chronic pruritic skin disorder characterized by amyloid deposition in the skin without evidence of visceral involvement.  It is characterized by discrete, intensely pruritic, hyperkeratotic papules that may coalesce into plaques. Lesions are found mainly on the anterior legs, but can occur on the back, forearms, and thighs.  Current treatments are unsatisfactory, with high relapse rates, adverse effects, and treatment failures. Therapeutic options include topical and intralesional corticosteroids, dermabrasion,  scalpel scraping, etretinate, calcipotriene, topical dimethyl sulfoxide, UV-B therapy,  and cyclophosphamide.