Amyloidosis, Lichen

Diagnosis: Amyloidosis, Lichen

Intensely pruritic, red-brown hyperkeratotic papules on the pretibial surfaces.

Clinical Presentation

Intensely pruritic, red-brown hyperkeratotic papules on the pretibial surfaces.

Clinical History

Submitted by Alaa Saad. Originally posted March 4, 2011.

Treatment

See case discussion.

Differential Diagnosis

• Lichen simplex chronicus • Prurigo nodularis • Hypertrophic lichen planus • Notalgia paresthetica

Key Learnings

• Primary cutaneous amyloidosis — amyloid derived from keratin • Intensely pruritic, hyperpigmented, hyperkeratotic papules on pretibial shins • "Rippled" or "corrugated" pattern • Common in Southeast Asian populations • Congo red: apple-green birefringence under polarized light • NOT associated with systemic (AL) amyloidosis

Tags: amyloidosis, lichen, alaa saad