Dermographism Urticaria Differential Diagnoses

Updated: Jun 11, 2018
  • Author: Simone Laube, MD, MRCP; Chief Editor: Dirk M Elston, MD  more...
  • Print

Diagnostic Considerations

Systemic mastocytosis and urticaria pigmentosa are associated with a positive Darier sign.

Forms of false dermographism (superficially similar conditions that are not associated with urticaria) must be ruled out. These include the following:

  • White dermographism – This is a blanching response resulting from capillary vasoconstriction after skin stroking and is more pronounced in persons with atopy

  • Black dermographism – This is a black or greenish discoloration of the skin occurring after contact with certain metallic objects

  • Yellow dermographism – This probably results from bile pigment deposits in the skin

Also consider latex allergy. Golberg et al presented a case series of 15 patients with symptomatic dermographism mimicking the symptoms of latex allergy, most commonly on the hands and genitalia. [12] Young atopic females and those in occupations involving regular use of gloves were more likely affected. Additionally, a flowchart has been devised to help guide clinicians in assessing patients with glove-related hand urticaria. [13]

Differential Diagnoses