Vesiculobullous Diseases
Epidermolysis Bullosa
Etiology • A diverse group of predominantly cutaneous, but also mucosal,
mechanobullous diseases • Inherited form: autosomal dominant or recessive patterns may
occur • Acquired form (acquisita): autoimmune from autoantibodies
(immunoglobulin G [IgG]) to type VII collagen deposited within the basement membrane zone and upper dermis or lamina propria
Clinical Presentation • Variable, depending upon the specific form of many subtypes
recognized • Mucosal lesions range in severity from mild to debilitating,
Etiology • A diverse group of predominantly cutaneous, but also mucosal,
mechanobullous diseases • Inherited form: autosomal dominant or recessive patterns may
occur • Acquired form (acquisita): autoimmune from autoantibodies
(immunoglobulin G [IgG]) to type VII collagen deposited within the basement membrane zone and upper dermis or lamina propria
Clinical Presentation • Variable, depending upon the specific form of many subtypes
recognized • Mucosal lesions range in severity from mild to debilitating,
depending on subtype: • Inherited forms have wide range of oral mucosal
involvement, with most severe form (autosomal recessive, dermolytic) also demonstrating enamel hypoplasia and caries
• Acquisita form with mucous membrane pemphigoid variant shows oral and conjunctival erosions/blisters
• Mucosal involvement absent in several variants • Scarring and stricture formation common in severe recessive
forms • Mucosa is often friable, but it may be severely blistered, erod-
ed, or ulcerated. • Loss of oral anatomic landmarks may follow severe scarring
(eg, tongue mucosa may become smooth and atrophic with episodes of blistering and scarring).
• Obliteration of vestibules, reduction of oral opening, ankyloglossia
• Scarring can be associated with atrophy and leukoplakia, with increased risk for squamous cell carcinoma development.
Microscopic Findings • Bullae vary in location depending upon the form that is present:
• Intraepithelial in nonscarring forms • At epithelial–connective tissue junction in dystrophic forms • Subepithelial/intradermal in scarring forms
• Ultrastructural findings are as follows: • Intraepithelial forms associated with defective cytokeratin
groups • Junctional forms associated with defective anchoring
filaments at hemidesmosomal sites (epithelial–connective tissue junction)
• Dermal types demonstrate anchoring fibril or collagen destruction.
Diagnosis • Distribution of lesions • Family history • Microscopic evaluation • Ultrastructural evaluation • Immunohistochemical evaluation of basement membrane zone
using specific labeled antibodies as markers for site of blister formation
Differential Diagnosis • Varies with specific form • Generally includes the following:
• Bullous pemphigoid • Mucous membrane (cicatricial) pemphigoid • Erosive lichen planus • Dermatitis herpetiformis • Porphyria cutanea tarda • Erythema multiforme • Bullous impetigo • Kindler syndrome • Ritter’s disease
• Intraepithelial in nonscarring forms • At epithelial–connective tissue junction in dystrophic forms • Subepithelial/intradermal in scarring forms
• Ultrastructural findings are as follows: • Intraepithelial forms associated with defective cytokeratin
groups • Junctional forms associated with defective anchoring
filaments at hemidesmosomal sites (epithelial–connective tissue junction)
• Dermal types demonstrate anchoring fibril or collagen destruction.
Diagnosis • Distribution of lesions • Family history • Microscopic evaluation • Ultrastructural evaluation • Immunohistochemical evaluation of basement membrane zone
using specific labeled antibodies as markers for site of blister formation
Differential Diagnosis • Varies with specific form • Generally includes the following:
• Bullous pemphigoid • Mucous membrane (cicatricial) pemphigoid • Erosive lichen planus • Dermatitis herpetiformis • Porphyria cutanea tarda • Erythema multiforme • Bullous impetigo • Kindler syndrome • Ritter’s disease
Treatment • Acquisita form:
• Some recent success with colchicine and dapsone • Immunosuppressive agents including azathioprine,
methotrexate, and cyclosporine may be effective • Acquisita and inherited forms:
• Avoidance of trauma • Dental prevention strategies including extra-soft brushes,
daily topical fluoride applications, dietary counseling
Prognosis • Widely variable depending on subtype
• Some recent success with colchicine and dapsone • Immunosuppressive agents including azathioprine,
methotrexate, and cyclosporine may be effective • Acquisita and inherited forms:
• Avoidance of trauma • Dental prevention strategies including extra-soft brushes,
daily topical fluoride applications, dietary counseling
Prognosis • Widely variable depending on subtype