Pemphigus foliaceus autoantibodies bind both epidermis and squamous mucosal epithelium, but tissue injury is detected only in the epidermis. The Cooperative Group on Fogo Selvagem Research.

ABSTRACT

BACKGROUND: Fogo selvagem (FS) is an autoimmune intraepidermal blistering disease mediated by antidesmosomal autoantibodies. Patients with FS do not have mucosal lesions despite extensive skin involvement. OBJECTIVE: Our purpose was to evaluate the epidermis and the oral epithelium of patients with FS as targets of antidesmosomal autoantibodies. METHODS: Fifteen patients were studied clinically, histologically, and immunologically. Biopsy specimens from the skin and the oral mucosa were studied by light microscopy and direct immunofluorescence. The serum of each of these patients was also titrated by indirect immunofluorescence. RESULTS: All patients showed skin lesions and subcorneal acantholyis, but none exhibited oral blisters or erosions. Direct immunofluorescence analysis demonstrated the presence of tissue-bound autoantibodies in both the epidermis and the oral epithelium of all patients with FS. Antiepidermal autoantibodies were also found in the sera of the patients. CONCLUSION: Relevant epitopes on desmoglein 1 molecules of oral epithelium may not be available to react with pathogenic FS autoantibodies.