B16. Primary skin lesions, basics of dermatohistopathology

From greek.doctor
  • Flat lesions
    • Macule
      • A flat skin lesion < 1 cm in size with discolouration
    • Patch
      • A flat skin lesion > 1 cm in size with discolouration
  • Infiltrative lesions
    • Papule
      • An elevated palpable skin lesion < 0,5 cm in size
      • Epidermal
    • Plaque
      • An elevated palpable skin lesion > 0,5 cm in size
      • Intradermal
    • Tuber
      • An elevated palpable skin lesion whose infiltration involves the entire depth of the dermis
    • Nodule
      • A circumscribed elevated lesion > 1 cm
      • In dermis and subcutis
    • Tumor
      • Large solid mass of tissue
  • Fluid-filled lesions
    • Vesicle
      • Small fluid-containing lesion
      • Intraepidermal
    • Bulla
      • Large fluid-containing lesion
      • Intraepidermal or subepidermal
    • Urtica/wheal
      • Transient oedema in the dermis
    • Pustule
      • Collection of pus in or below the epidermis
  • Dermatopathological terms
    • Acantholysis
      • Separation of epidermal cells due to dissolution of desmosomes
      • E. g. in pemphigus vulgaris
    • Acanthosis
      • Hyperplasia of stratum spinosum
      • E.g. in acanthosis nigricans
    • Hypergranulosis
      • Hyperplasia of stratum granulosum
      • E.g. in lichen planus
    • Hyperkeratosis
      • Hyperplasia of stratum corneum
      • E.g. in psoriasis
    • Papillomatosis
      • Hyperplasia and enlargement of dermal papillae
    • Parakeratosis
      • Keratinocytes in stratum corneum retain their nuclei
      • E.g. in
        • Psoriasis
        • Dandruff
    • Spongiosis
      • Intraepidermal oedema
      • E.g. in
        • Atopic dermatitis
        • Allergic contact dermatitis