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Blister

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Blister, Vesiculobullous, Vesiculobullous Rash, Vesicle, Bulla, Bullous Disease, Bullous Condition, Autoimmune Bullous Dermatoses, Acantholysis, Acantholytic

  • Definitions
  1. Vesicle
    1. Raised fluid filled lesion <0.5 cm diameter
  2. Bulla
    1. Raised fluid filled lesion >0.5 cm diameter
  • Pathophysiology
  1. Develops at intersection of skin levels
    1. Epidermal layers
    2. Epidermal-Dermal junction (Deeper lesions)
  • Types
  1. Subcorneal Vesicle or bulla
    1. Occurs immediately below Stratum Corneum
    2. Examples
      1. Bullous Impetigo
      2. Pemphigus Foliaceus (Superficial Pemphigus)
  2. Spongiosis (e.g. Allergic Contact Dermatitis)
    1. Intracellular edema in epidermal layers
  3. Acantholysis
    1. Occurs in all forms of Pemphigus
    2. Desmosomes (intracellular bridges) disrupted
    3. Results in loss of Keratinocyte cohesion
    4. Acatholytic cells become rounded (from polyhedral)
  4. Viral induced cell destruction (e.g. Varicella)
    1. Epidermal cells expand as they degenerate
  • Signs
  1. Thin, translucent walls
  2. Contains serum, lymph, blood, or extracellular fluid
  3. Nikolsky's Sign
    1. Pemphigus Vulgaris
    2. Stevens-Johnson Syndrome
    3. Toxic Epidermal Necrolysis
  • Evaluation
  • Acute Blistering Condition
  1. Consider Exposures
    1. Insects
    2. Pets
    3. Medications (e.g. Drug-Induced Bullous Disease)
    4. Contact Dermatitis allergens and irritants
    5. Infection (e.g. Bullous Impetigo)
  2. Consider Trauma
    1. Burn
    2. Friction injury
  3. Observe for mucosal lesions
  4. Consider systemic causes
    1. Diabetes Mellitus
    2. Systemic Lupus Erythematosus
    3. Thyroid disease
    4. Porphyria
    5. Celiac Sprue
  • Labs
  1. Tzanck Smear and viral culture
    1. Indicated for grouped herpetiform Vesicles
  2. Biopsy with Immunofluorescence
    1. Indicated for bullae in older patients
    2. Rule-out Pemphigus or Pemphigoid
  • Differential Diagnosis
  • Vesicle or Bulla Depth
  • References
  1. Goldman (2000) Cecil Medicine, p. 2283
  2. Habif (1996) Dermatology, Mosby-Year, p. 9-10
  3. Rye (1997) Am Fam Physician 55(8):2709-18 [PubMed]