Skin inflammatory (nontumor)
Spongiotic, psoriasiform and pustular reaction patterns
Prurigoform acanthosis

Author: Mowafak Hamodat, M.D., MB.CH.B, MSc., FRCPC (see Authors page)

Revised: 15 October 2018, last major update August 2011

Copyright: (c) 2002-2018,, Inc.

PubMed Search: Acanthosis [title]

Cite this page: Hamodat, M. Prurigoform acanthosis. website. Accessed December 11th, 2018.
Definition / general
  • A chronic spongiotic dermatitis due to sustained skin irritation, often from rubbing or scratching
Microscopic (histologic) description
  • Epidermis shows hyperkeratosis, acanthosis and pseudoepitheliomatous hyperplasia
  • Sub-epidermal fibrin deposition and mild spongiosis with dermal scarring
  • Dermis shows vascular hyperplasia with dilated vessels in papillary dermis and reticular dermis
  • New vessel formation with perivascular, mild infiltrate of lymphocytes, some histiocytes, plasma cells and occasional eosinophils; mast cells are normal in number
  • Lymphoid follicles may be seen
  • Nerves may appear normal, increased in number or hyperplastic
Differential diagnosis
  • Cutaneous T cell lymphoma, hypertrophic actinic keratosis (atypia), early keratoacanthoma (atypia)