Lichen planus and coexisting lupus erythematosus versus lichen planus-like lupus erythematosus. Clinical, histologic, and immunopathologic considerations.

A middle-aged black woman presented initially with painful cutaneous plaques that were located at various sites and that were diagnosed histologically as lichen planus. Standard light microscopic examination showed histopathologic variants of lichen planus. Direct immunofluorescence of a skin lesion had negative results for any of the lupus erythematosus bands but did reveal hyaline bodies in the deep cellular layer of the epidermis and the superficial layer of the dermis. These findings were compatible with either lichen planus or lupus erythematosus. However, both the clinical course of the eruption and the antinuclear antibody tests showed that the immunofluorescent antinuclear antibody pattern of large, speckle-like threads were consistent with lupus erythematosus. Furthermore, the large, speckle-like, thready antinuclear antibody pattern, which has been shown to be a marker for a benign subset of lupus erythematosus, is not seen in lichen planus. Lichen planus--like lupus erythematosus was therefore the more likely diagnosis.