Pemphigus

Key Features

Essentials of Diagnosis

• Relapsing crops of skin bullae

• Often preceded by mucous membrane bullae, erosions, and ulcerations

• Superficial detachment of the skin after pressure or trauma variably present (Nikolsky sign)

• Acantholysis on biopsy

• Immunofluorescence studies and serum ELISA for pathogenic antibodies are confirmatory

General Considerations

• Pemphigus is an uncommon intraepidermal blistering disease occurring on skin and mucous membranes

• Caused by autoantibodies to adhesion molecules expressed in the skin and mucous membranes

• There are several forms of pemphigus

  • Pemphigus vulgaris and its variant, pemphigus vegetans

  • Pemphigus foliaceus, which is more superficially blistering, and its variant, pemphigus erythematosus

  • Paraneoplastic pemphigus

• The vulgaris form begins in the mouth in over 50% of cases

• The foliaceus form is especially apt to be associated with other autoimmune diseases, or it may be drug-induced

• Paraneoplastic pemphigus, a unique form of the disorder, is associated with numerous types of benign and malignant neoplasms but most frequently non-Hodgkin lymphoma

Demographics

• All forms may occur at any age but most commonly in middle age

Clinical Findings

Symptoms and Signs

• An insidious onset of flaccid bullae, crusts, and erosions in crops or waves

• The bullae appear spontaneously and are tender and painful when they rupture

• In pemphigus vulgaris, lesions often appear first on the oral mucous membranes, and these rapidly become erosive

• The scalp is another site of early involvement

• Rubbing a cotton swab or finger laterally on the surface of uninvolved skin may cause easy separation of the epidermis (Nikolsky sign)

• Downward pressure on a fresh bulla may cause lateral spread (Asboe-Hansen sign)

• Pemphigus vegetans presents as erosive vegetating plaques, most often in intretriginous areas

• Pemphigus foliaceus

  • A superficial form of pemphigus where cutaneous lesions often present as flaccid bullae that quickly evolve into superficial erosions and thin pink plaques with overlying scale

  • Mucosal lesions are rare

• Pemphigus erythematosus

  • Has overlapping features of pemphigus foliaceus and lupus erythematosus

  • Presents with flaccid bullae that develop overlying scale and crust in a photodistributed area

  • Mucosal lesions are rare

• Paraneoplastic pemphigus

  • Histologically and immunologically distinct from other forms

  • Oral lesions predominate

  • Cutaneous erythematous plaques resembling erythema multiforme are characteristic

  • Survival rates are low because of the underlying malignancy

Differential Diagnosis

• Erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis

• Drug eruptions

• Bullous impetigo

• Contact dermatitis

• Dermatitis herpetiformis

• Bullous pemphigoid

• Subacute cutaneous lupus erythematosus

Diagnosis

Laboratory Tests

• The diagnosis is made by light microscopy and by direct and indirect immunofluorescence microscopy

• Autoantibodies to intercellular adhesion molecules can be detected with ELISA assays

Treatment

Medications

• See Table ...