Etiology

  • Genetic filaggrin mutation → impaired skin barrier

  • Atopic history (asthma, allergic rhinitis)

  • Environmental triggers (soaps, cold weather)

Pathogenesis

  • Barrier dysfunction → increased water loss → allergen penetration

  • Th2-mediated immune response → chronic inflammation

Clinical Features

  • Pruritus (hallmark)

  • Eczematous patches on flexor surfaces

  • Infants: face and extensor surfaces

  • Lichenification from chronic scratching

  • Secondary infections (S. aureus)

Treatment

  • Emollients

  • Topical steroids

  • Calcineurin inhibitors (tacrolimus)

  • Antihistamines for itch

  • Dupilumab (severe cases)