Psoriasiform dermatitides: A brief review.

Psoriasis vulgaris (PV)-the prototypical "psoriasiform" dermatitis-may assume a spectrum of histologic appearances, depending on whether it has been treated or not. Because of that relative lack of morphological uniformity, other skin disorders that feature epidermal acanthosis, with or without associated inflammation, may be confused diagnostically with PV. This brief review considers the clinicopathologic attributes of PV and its imitators, including chronic spongiotic dermatitides, lichen simplex chronicus, prurigo nodularis, pityriasis rubra pilaris, psoriasiform secondary syphilis, and Reiter syndrome.