Abstract
We presented a 39-year-old female patient who had suffered from clinically typical erythema elevatum diutinum for two years. The erythematous plaques were distributed symmetrically on the extensor surface of all the interpharyngeal joints of her fingers. There were no systemic signs or symptoms. Laboratory studies were all within normal limits, as was the chest radiogram. Histologically, the epidermis was invaded by the infiltrate of neutrophils and showed acanthosis and hyperkeratosis. There were dense perivascular infiltrates of lymphocytes and histiocytes in the dermis. However, there were no obvious findings of leukocytoclastic vasculitis. The lesion was diagnosed as erythema elevatum diutinum in a chronic condition, and it was treated with dapsone (75 mg t. i. d.) resulting in an almost complete clearing of the eruptions within eight months.
