dermatitis herpetiformis

see also:

• dermatology
• dermnetnz

• rare, chronic pruritic papulo-vesicular auto-immune skin disorder mainly occurring in people with coeliac disease which accounts for 80% of cases, other associations not related to gluten intolerance include:
  • IgA deficiency
  • psoriasis
  • downs_syndrome
  • primary biliary cirrhosis
• 2/3rds of patients are male, and usually affects young adults
• associated with HLA DQ2 DQ8

• very itchy papules (“prurigo papules”) and vesicles which arise on normal or reddened skin
• often symmetric and tends to involve scalp, shoulders, buttocks, elbows and knees
• often resembles scabies or dermatitis

• screen for coeliac disease, IgA deficiency
• IgA antibodies directed against epidermal transgluataminase (eTG).
• skin biopsy to confirm Dx - IgA in dermal papillae with neutrophils and eosinophils

• gluten free diet if coeliac disease
• dapsone 50-300mg/d as per dermatologist advice