Pemphigus vulgaris

Definition

Pemphigus vulgaris is an autoimmune skin disorder characterized by blistering of the skin and mucous membrane.

Causes, incidence, and risk factors

Pemphigus involves blistering of the outer (epidermal) layer of the skin and mucous membranes. It is an autoimmune disorder in which the immune system produces antibodies against specific proteins in the skin and mucous membrane. These antibodies produce a reaction that leads to a separation of epidermal cells (acantholysis). The exact cause of the development of antibodies against the body's own tissues (autoantibodies) is unknown.

Sometimes pemphigus appears in reaction to medications, although this is rare. Pemphigus may be a side effect of ACE inhibitors (such as Elanapril) or chelating agents (such as penicillamine).

Pemphigus is uncommon. It occurs almost exclusively in middle-aged or older people of all races and ethnic groups. About one-half of the cases of pemphigus vulgaris begin with blisters in the mouth, followed by skin blisters. The blisters (bullae) are relatively asymptomatic, but the lesions become widespread and complications develop rapidly and may be debilitating or fatal.

Symptoms

• Skin lesions which may be:
  o Recurrent or relapsing
  o Blistering, flaccid
  o Mouth or skin ulcers
  o Draining, oozing, crusting
  o Located on the mucous membrane of the mouth
  o Located on the scalp, trunk or other skin areas
  o Spreading to other skin areas
  o Peeling superficially or detaching easily
  

Signs and tests

• Nikolsky's sign is positive - when the surface of uninvolved skin is rubbed laterally with a cotton swab or finger, the skin separates easily.
  
• A skin lesion biopsy shows acantholysis.
  
• An examination of the biopsy tissue with immunofluorescence confirms pemphigus.
  
• The Tzanck test of a smear from the base of a blister shows acantholysis.
  

Treatment
Severe cases of pemphigus are treated similarly to severe burns. Treatment may require hospitalization, including care in a burn unit or intensive care unit. Treatment is aimed at reducing symptoms and preventing complications.

Intravenous fluids, electrolytes, and proteins may be required. Mouth ulcers, if severe, may mean intravenous feeding is needed. Anesthetic mouth lozenges may reduce the pain of mild to moderate mouth ulcers. Antibiotics and antifungal medications may be appropriate to control or prevent infections.