Bullous Pemphigoid (BP)

Bullous Pemphigoid (BP)

• Bullous pemphigoid affects elderly people, with onset usually after 60 years of age.

• The blister in BP is subepidermal with an intact roof.

• Has a benign course if compared to PV.

Pathogenesis

• There is linear deposition of IgG & complement factors against proteins (Ags) at the dermo-epidermal junction.

  • The IgG antibodies bind to main antigens the BP Ag type 1 and BP Ag type 2 found in the hemidesmosomes in the lamina lucida.

  • Complement is then activated, starting an inflammatory cascade which results in separation of the lamina lucida.

Structure of the Epidermis and Target Antigens/Cleavage in Bullous Diseases

Clinical Featuresz

• Pemphigoid is a chronic, usually itchy, blistering disease.

  • Early stage of the disease is characterized by pruritus.

  • Bullae may be centered on erythematous and urticated base.

• Large tense bullae found anywhere on the skin

• The flexures are often affected; inner aspect of the thigh, flexure surface of forearms, axilla, groin, and lower abdomen

• The mucous membranes usually are not affectedZ

• The Nikolsky Asboe signs are negative Z

Bullous Pemphigoid

tense

Bullous Pemphigoid histology

![[Bullous Pemphigoid BP-1747636888441.webp|290x185]] ![[Bullous Pemphigoid BP-1747636904949.webp|290x215]] linear appearance

Prognosis

• Untreated bullous pemphigoid runs a chronic, self-limiting course over a number of months or years.

• The disease duration is usually 3-6 years, with most patients achieving complete remission off treatment.

Treatment

1. Topical and systemic steroids are the mainstay of treatment → For localized BP, very potent topical steroids are often sufficient

2. Low dose systemic steroid 30 to 40 mg/day

   • Corticosteroid therapy has lowered morbidity from the disease considerably and most patients achieve remission off therapy