Unique aspects of a lesion of erythema elevatum diutinum.

A 70-year-old man with erythema elevatum diutinum developed new lesions on his right hand 4 years after initiation of treatment with dapsone. An unusual protruberant appearance of these lesions grossly and a peculiar fibrosing quality histopathologically of one lesion are features that, to our knowledge, have not been reported previously.