Etiology • An autoimmune disease where antibodies are directed toward
the desmosome-related proteins desmoglein 3 or desmoglein 1 • A drug-induced form exists with less specificity in terms of
immunologic features, clinical presentation, and histopathology
Clinical Presentation • Over 50% of cases develop oral lesions as the initial
manifestation • Oral lesions develop in 70% of cases • Painful, shallow irregular ulcers with friable adjacent mucosa • Nonkeratinized sites (buccal, floor, ventral tongue) often are
initial sites affected • Lateral shearing force on uninvolved skin or mucosa can
the desmosome-related proteins desmoglein 3 or desmoglein 1 • A drug-induced form exists with less specificity in terms of
immunologic features, clinical presentation, and histopathology
Clinical Presentation • Over 50% of cases develop oral lesions as the initial
manifestation • Oral lesions develop in 70% of cases • Painful, shallow irregular ulcers with friable adjacent mucosa • Nonkeratinized sites (buccal, floor, ventral tongue) often are
initial sites affected • Lateral shearing force on uninvolved skin or mucosa can
produce a surface slough or induce vesicle formation (Nikolsky sign)
Microscopic Findings • Separation or clefting of suprabasal from basal layer of
epithelium • Intact basal layer of surface epithelium • Vesicle forms at site of epithelial split • Nonadherent spinous cells float in blister fluid (Tzanck cells) • Direct immunofluorescence examination positive in all cases • IgG localization to intercellular spaces of epithelium • C3 localization to intercellular spaces in 80% of cases • IgA localization to intercellular spaces in 30% of cases • Indirect immunofluorescence examination positive in 80%
of cases • General correlation with severity of clinical disease
Diagnosis • Clinical appearance • Mucosal manifestations • Direct/indirect immunofluorescent studies
Differential Diagnosis • Mucous membrane (cicatricial) pemphigoid • Erythema multiforme • Erosive lichen planus • Drug reaction • Paraneoplastic pemphigus
Vesiculobullous Diseases 73
Treatment • Systemic immunosuppression • Prednisone, azathioprine, mycophenolate mofetil,
cyclophosphamide • Plasmapheresis plus immunosuppression • IVIg for some recalcitrant cases • See “Therapeutics” section for details.
Prognosis • Guarded • Approximately a 5% mortality rate secondary to long-term
systemic corticosteroid–related complications