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For further information, see CMDT Part 6-44: Pemphigus
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Essentials of Diagnosis
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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
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General Considerations
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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 chronic lymphocytic leukemia, Castleman disease, B cell lymphoma, plasmacytoma, and thymoma
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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)
Pemphigus vegetans presents as erosive vegetating plaques, most often in intertriginous areas
Pemphigus foliaceus
Pemphigus erythematosus
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
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Differential Diagnosis
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Erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis
Drug eruptions
Bullous impetigo
Contact dermatitis
Dermatitis herpetiformis
Bullous pemphigoid
Subacute cutaneous lupus erythematosus
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