Bullous Skin Lesion

BLISTERING SKIN LESION
 


  • Causes of Acute Non-pustular Exfoliative Dermatoses Case 20-2009
    • SJS  (30% or less surface area involved) 
    • SJS / TEN (30-50%)
    • TEN (50% or more) Case 20-2009
      • SJS and TEN have nearly identical histology
      • Distinguished mainly by surface area involved
      • The eruptions are characteristically painful, often requiring analgesics. Photophobia, dysphagia, and dysuria ref lect mucosal involvement 
      • Constitutional Symptoms are present, and often may have visceral organ involvement
      • Causes: Often Medications
        • Antibiotics
        • NSAIDS
        • Anti-convulsants
        • Allopurinol
    • Erythema Multiforme or Bullus Erythema Multiforme Case 20-2009
      • The characteristic lesion is the target lesion, consisting of three zones — a central dusky discoloration or bulla, surrounded by a pale-colored edematous ring, encircled by erythema 
      • typically preceded by an outbreak of herpes simplex virus 
      • self-limited, often recurrent con- dition that typically persists for 1 to 4 weeks and typically requires only symptomatic care 
    • DRESS
      • Rash begins with facial and hand swelling 
      • Characterized by presence of both pustules and desquamation
      • Typically 2-6 weeks after start of new medications
      • Lymphadenopathy, Hepatomegaly, Abnormal LFT are seen as well 
    • Generalized Bullus Fixed Drug Eruption (GBFDE) JAMA 2014
      • Diagnosis can be made clinically. 
        • Purplish Discoloration
        • Close temporal relationship between drug intake 
        • In contrast to SJS / TEN, GBFDE is characterized by 
          • Paucity of constitutional symptoms and visceral complications,
          •  well demarcated blisters, erythematous patch,
          • absence of small spots or target lesions, 
          • history of a similar eruption, and 
          • onset within hours of exposure to the associated drug. 
        • Unlike in GBFDE, respiratory involvement has been documented in 30% of patients with toxic epidermal necrolysis, hepatic involvement in 63%, and renal involvement (proteinuria and hematuria) in 80%  
      • Skin Biopsy
        • vacuolar interface dermatitis in the histological findings of bullous erythema multiform overlaps with FDE and Stevens-Johnson syndrome/toxic epidermal necrolysis. However, prominent pigment incontinence and eosinophil infiltrates favor FDE
        • Moreover, the number of eosinophils present in patients with bullous pemphigoid is usually more than that in those with FDE and distributed along the dermoepidermal junction or in the blisters unlike perivascular infiltrates in FDE.10
      • Patch testing and oral rechallenge are sometimes used to reveal the causative drug but are not always practical. 
      • Patch tests have been shown to provide positive rates ranging from 40% to 86%. 
  • Autoimmune Blistering Disease
    • pemphigus vulgaris
    • bullous pemphigoid 


  • Epidermolysis bullosa 
 





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