Lichen Amyloidosis

A 57-year-old man presents for evaluation of an intensely itchy eruption involving both forelegs. He is ostensibly in good health and denies medication use.

Key point: This is a distinctly unique presentation consisting of close-set, monomophous, red-brown papules with slight scale, located on the shins. The diagnosis is almost always lichen amyloidosis, a form of primary cutaneous amyloid. Itching is typically severe.

Treatment: There is no specific therapy. Oral antihistamines may be sufficient to relieve itching. UVA and UVB phototherapy may also help alleviate itching, although the papules will persist.

Note: This is the most common form of amyloid deposition in the skin. It is NOT associated with systemic disease, but is solely a cutaneous malady. Lichen amyloid is more common in late middle age (50 to 60 years) and in men.