Blister

Bullous Pemphigoid

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Bullous Pemphigoid

  • Epidemiology
  1. Age of onset 60 to 80 years old
  2. Men and women affected equally
  3. Incidence: 7 per 1 million in U.S.
  • Pathophysiology
  1. Autoimmune Subepidermal Blistering
  2. Mediated by IgG auto-antibodies that target basement membrane hemidesmosome at dermal-epidermal junction
  • Causes
  1. Idiopathic (85% of cases)
  2. Specific trigger (15% of cases)
    1. Radiation Therapy
    2. Burn Injury
    3. Immunization
    4. Surgery
    5. Trauma
    6. Medications (esp. Furosemide)
  • Symptoms
  1. Pruritus
  2. Lesions may be tender at borders
  • Signs
  1. First phase (months)
    1. Initial Urticarial or erythematous lesions
    2. Flexor creases (e.g. axilla, inguinal) are often affected
    3. Intense Pruritus
  2. Second phase
    1. Develops into large tense bullae after weeks to months
      1. Contain clear fluid or may at times be hemorrhagic
    2. Diffuse cutaneous involvement
      1. Often involves lower legs, Forearms, thighs, groin
      2. Also involves Abdomen
      3. Mucusa much less affected than in pemphigous vulgaris
    3. No scar formation
    4. Milia may form at previously involved sites
    5. Nikolsky Sign is absent (contrast with Pemphigus lesions)
      1. Thick walled bullae
  • Labs
  1. Histology
    1. Subepidermal Blister
    2. Superficial dermal inflammation (Eosinophils)
  2. Immunofluorescence
    1. IgG and C3 deposition along basement membrane zone
  • Management
  1. First-Line
    1. Prednisone 1 mg/kg/day
    2. Methotrexate may be used for Prednisone intolerance
    3. Topical Corticosteroids in localized mild cases
  2. Adjunctive agents (Corticosteroid sparing)
    1. Azathioprine
    2. Mycophenolate mofetil
    3. Leflunomide
    4. Cyclophosphamide
    5. Intravenous Immunoglobulin
    6. Dapsone
    7. Plasmapheresis
    8. Tetracycline
  • Complications
  1. Secondary Skin Infection
  • Course
  1. Self-limited condition
  2. Chronic in many cases with exacerbations and remissions
  3. Remits with treatment by 6 years in 50% of cases