Extensive lichen amyloidosus refractory to DMSO.

While lichen amyloidosus reportedly may respond to dimethyl sulfoxide (DMSO) application, we present a patient whose lesions were refractory to this agent. This Japanese woman had chronic extensive lichen amyloidosus, mainly on her trunk. Her 10-year history of using nylon towels was the suspected cause. The application of DMSO ointment had no clinical effect, and the amyloid deposits persisted in the histological specimens despite the treatment. The administration of a topical corticosteroid led to gradual clinical improvement.