Pemphigus vulgaris
Pemphigus vulgaris is an autoimmune intraepidermal blistering disease in which IgG autoantibodies against desmoglein 3, often with desmoglein 1, destroy keratinocyte adhesion, producing flaccid, easily ruptured mucocutaneous bullae with a positive Nikolsky sign. Diagnosis is confirmed by skin biopsy with direct immunofluorescence and anti-desmoglein serology, and first-line treatment is rituximab 1,000 mg IV twice, two weeks apart, combined with a tapering corticosteroid course.
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What this article covers
- Overview
Definition: pemphigus vulgaris is an autoimmune, antibody-mediated (type II) hypersensitivity blistering disease in which IgG antibodies attack desmoglein 3, often together with desmoglein 1, the…
- Epidemiology
Incidence: estimated at 0.5 to 3.2 cases per 100,000 persons per year, rising further with older age.
- Risk factors
Ashkenazi Jewish ancestry: the strongest recognized demographic association.
- Pathophysiology
Type II hypersensitivity against desmosomes: IgG autoantibodies target desmoglein 3, and often desmoglein 1, the cadherin-family adhesion proteins of the desmosome that provide structural support through intermediate filament interactions.
- Clinical features
Diagnostic pattern: flaccid oral or other mucosal bullae that rupture easily to leave painful, irregularly bordered erosions, together with a positive Nikolsky sign (lateral pressure on perilesional…
- Differential diagnosis
Paraneoplastic pemphigus: painful oral, conjunctival, esophageal, and laryngeal erosions with a polymorphous eruption and possible fatal respiratory involvement, unlike the mucocutaneous-only disease…
- Diagnosis
Diagnose with skin biopsy plus direct immunofluorescence and confirm with serology: the clinching basis is a perilesional skin biopsy showing suprabasilar acantholysis (the "row of tombstones"…
- Management
First, screen for hepatitis B with HBsAg and anti-HBc before initiating first-line B-cell-depleting therapy, since hepatitis B reactivation is a recognized risk of this treatment.
- Complications
Death from infection or disease severity if untreated: before effective immunosuppressive treatment, mortality from pemphigus vulgaris was high, and it remains possible today, particularly from infection.
- Prognosis
Mortality was high before modern immunosuppression and changed once oral glucocorticoids and steroid-sparing agents became standard, though death remains possible today.
- Prevention
Screen hepatitis B (HBsAg and anti-HBc) before every course of rituximab to identify patients at risk for reactivation before B-cell-depleting therapy.
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