Lichen planus pemphigoides. Immunofluorescence findings

A 56-year-old woman developed a vesicular and bullous eruption followed by an efflorescence of lichenoid papules. The clinical and histologic features of this case were consistent with a diagnosis of lichen planus pemphigoides. Direct and indirect immunofluorescence studies demonstrated both in vivo-bound and circulating IgG with specificity for the epidermal basement membrane zone. A common pathogenic immunologic mechanism may exist for both lichen planus and lichen planus pemphigoides, which we believe are clinical variants of a similar disease process.