Pemphigus Vulgaris : A Vesiculobullous Disease

Overview:

• Derieved : Greek word pemphix meaning bubble.
• Named by Wichman in 1791.
• Pemphigus refers to a group of autoimmune blistering diseases of the skin and mucous membranes characterized by formation of flaccid bullae.

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Pathophysiology

• Mediated by circulating autoantibodies directed against keratinocyte cell surfaces.
• Binding of IgG autoantibodies to keratinocyte desmosomes and to desmosome-free areas of the keratinocyte cell membrane.
• Loss of cell-cell adhesion,acantholysis..

PV antigen: desmoglein 1 and desmoglein 3.

Risk factors: Genetic, Age factor, And Associated with other diseases like Thymoma and Myasthenia Gravis.

Sex: Male=Female .More in adolescent girl than boys.

Age:Adults (50-60 years)

General Health: Poor

Antibodies: IgGin Intracellular substance directed against Keratinocytes.

Clinical Features:

Site: Flexural surfaces, trunk, back, axilla, abdomen

The 3 primary subtypes:

• Pemphigus Vegetans
• Pemphigus Foilaceous
• Paraneoplastic Pemphigus.

Others: P. Erythematoides

1. 1. Skin:
   1. Superficial and flaccid blisters, which usually arises on normal-appearing skin but may be found on erythematous skin.
   2. New blisters usually are flaccid or become flaccid quickly and are filled with clear fluid that arises on normal skin or on an erythematous base. The blisters are fragile; therefore, intact blisters may be few. The contents soon become turbid, or the blisters rupture producing painful erosions, which is the most common skin presentation. Erosions often are large.
   3. Erythematous halo may be present around the lesion.
   4. Mucous membranes: Commonly Involved. Oral lesions in 50-70% of patients, and almost all patients have mucosal lesions. Sometimes it is sole manifestation of this disease.Intact bullae are rare in the mouth. Ill-defined, irregularly shaped, gingival, buccal or palatine erosions, painful and slow to heal. The erosions extend peripherally with shedding of the epithelium. (Conjunctiva,esophagus,labia, vagina, cervix, penis, urethra, and anus.)

• Drug-induced PV: penicillamine, captopril, Rifampin and emotional stress have recently been reported as triggers for PV.
• Pregnancy Induced.

Mucous membranes are usually affected first in PV. Mucosal lesions may precede cutaneous lesions by months.

Diagnosis:

• Nikolsky sign: In patients with active blistering, firm sliding pressure with a finger separates normal-appearing epidermis, producing erosion. This sign is not specific for PV.
• Asboe-Hansen sign: (Bulla Spreading sign) Lateral pressure on the edge of a blister may spread the blister into clinically unaffected skin.

• Giemsa Staining of Skin Sample
• Histopathology
• Direct and Indirect Immunofluorescence Assay.

Treatment:

Topical: Steroids and Antibiotics

Systemic: High Dose Prednisolone 80-120 mg Oral or Parenteral dose

If no new lesions appear, decrease dose by 5-10 mg/week

If new lesions appear, increase dose up to 200mg.

Others:

• Cyclophosphamide
• Methotrexate
• Antihistaminic

Plasmapheresis

Complications:

• Superadded Infections
• Erythroderma

Mortality Rate:

• 5-15%.

By Dr. Sujit Shrestha