Histopathological Study of Diffuse Idiopathic Melanoderma.

Histopathological study of clinically involved as well as normal skin in 30 cases of diffuse idiopathic melanoderma revealed increased melanin pigmentation of the basal in all the case, liquefactive degeneration,of basal cells in 20 cases, epidermal atrophy in l7 cases, melanophages in the, upper dermis 26 cases, and a perivascular or diffuse lympho-histiocytic infiltrate in 28 cases. There were distinct clinical and histopathplogical differences from lichen planus.