8. Pemphigus
The name is derived from the
Greek root "pemphix",
meaning "pustule”
• Rare, autoimmune mediated inflammatory blistering disorders
• M = F, equally affected genders
• Affects 4th – 6th decades of life
• Life threatening without treatment
• Variants include Pemphigus -
• Vulgaris (80%)
• Vegetans
• Foliaceus
• Erythematosus
• Paraneoplastic pemphigus
9. Diagnosis
Histological morphology; Acantholysis – the lysis of
intercellular adhesions that connect squamous epithelial
cells
• Skin biopsy specimen(s)
• Suprabasilar acantholysis Vulgaris
• The single layer of intact basal cells that form
the blister base likened to ‘tombstones’
• Subcorneal acantholysis Foliaceus
• Suprabasilar acantholysis & dyskeratotic
keratinocytes with basal cell vacuolization
10. Pathophysiology
• IgG autoantibodies result in dissolution of
intracellular attachments (Desmoglesins)
• Attacks epidermis mucosal epithelium
• Bullous diseases can be dramatic
• Bullae can occur in different levels within skin,
causing mild to dramatic blisters
• Variable superficial dermal infiltration by
lymphocytes, histiocytes, and eosinophils
accompany all forms of pemphigus
• Direct immunofluorescence – shows net-like
pattern of intercellular IgG deposits
11. History (Vulgaris)
• Pemphigus is the commonest type
• Can involve scalp, face, axilla, groin, trunk, points of pressure
• May present as oral ulcers, classically persisting for months before
skin involvement appears
• Primary lesions are superficial vesicles / bullae that rupture easily
• This leaves shallow erosions which are crusted
12. Treatment
• Regimens depend on patient’s age, degree of involvement, rate of progression,
and subtype of pemphigus.
• Systemic corticosteroids (eg. 1mg/kg Prednisolone oral OD) required for P.
Vulgaris, whereas topical corticosteroids (0.05% fluocinonide ointment topical
BD) can occasionally control P. foliaceus.
• One course of IV immunoglobulin (400 mg/kg 5/7 days) is safe for steroid
resistant disease.
• Other agents include; Dapsone, Hydroxychloroquine, Mycophenolate mofetil,
Azathioprine, Cyclophosphamide & Rituximab.
• Although steroid sparing agents are clinically effective, few controlled studies
demonstrate benefit.
• Tumour removal in paraneoplastic pemphigus is often curative, but in
malignancies can be resistant and require pulse methylpred, immuno-apheresis,
immunoablative cyclophosphamide & rituximab.
13. Prognosis
• Mainstay of treatment is immunosuppressive agents, which reduce
titre of pathogenic antibodies.
• Before use of corticosteroids, 60-90% of patients with vulgaris died
• Since introduction of steroids, dropped to 5-10% mortality rate
• Paraneoplastic relates to the type of cancer
• Benign tumours – usually lesions clear after tumour resection
• Malignant tumours (most commonly non-Hodgkin lymphoma) – have a
poorer prognosis and treatment does not entirely prevent mortality