Pemphigus vegetans – immunopathological findings in a rare variant of pemphigus vulgaris

A patient with painful erosions of the oral cavity and the labia minora developed multifocal blisters in inter‐triginous areas. These blisters eroded and evolved into papillomatous erosive vegetations. Histopathology and immunopathological investigations confirmed the diagnosis of pemphigus vegetans, mediated by IgG autoantibodies. The circulating IgG1 and IgG4 autoantibodies were exclusively directed against desmoglein 3, as shown by ELISA and indirect immunofluorescence studies. These IgG1 and IgG4 isotypes were also in vivo bound, as demonstrated with immunoperoxidase staining of perilesional skin. Our clinical, biochemical and immunopathological observations confirm the hypothesis that pemphigus vegetans is a variant of pemphigus vulgaris.