While being evaluated for moles, a mother asks whether the clinician can check out a photograph of her 13-year-old daughter who “gets these white lines” on her skin whenever she is scratched or pressure is applied. The lines rapidly fade. The mother states that her daughter is in good health and takes no medications. Her family history is positive for atopic dermatitis. The teenager is sensitive to poison ivy but has no other allergies.
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Dermatographism, also known as skin writing, is a localized wheal and flare reaction induced by mechanical pressure such as scratching or stroking or from constrictive clothing.1 Wheals occur within 5 minutes of pressure and may last up to 30 minutes. Young adults are most commonly affected by dermatographism with a peak onset at 20 to 30 years of age.2 The condition may be pruritic and is usually accompanied by varying degrees of erythema. White dermatographism, as exemplified by this patient, has been reported in persons with atopic dermatitis.3
Dermatographism may affect up to 5% of the general population.4 Most cases are idiopathic but some have been linked to drug reactions and infectious agents.5 Conditions associated with dermatographism include hyperthyroidism, diabetes, and pregnancy. The pathogenesis of dermatographism is believed to involve stimulation of mast cells and subsequent release of histamine. Histamine causes dilation of blood vessels and fluid extravasation into surrounding tissues resulting in redness and swelling.6
Asymptomatic patients with dermatographism do not require treatment. Avoidance of precipitating factors is often necessary to prevent episodes. Those bothered by pruritis may benefit from H1 and/or H2 antihistamines.2 Omalizumab is an option for persistent cases of dermatographism that impair quality of life.2
Amy DePalma, NP-C, is a nurse practitioner practicing at the DermDox Dermatology Center in Gilbert, PA. Stephen Schleicher, MD, is director of the DermDox Dermatology Centers, associate professor of medicine at Geisinger Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.
1. Kontou-Fili K, Borici-Mazi R, Kapp A, Matjevic LJ, Mitchel FB. Physical urticaria: classification and diagnostic guidelines. An EACCI position paper. Allergy. 1997;52(5):504-513. doi:10.1111/j.1398-9995.1997.tb02593.x
2. Nobles T, Muse ME, Schmieder GJ. Dermatographism. In: StatPearls [Internet]. StatPearls Publishing; 2022 Jan-. Updated February 23, 2022. Accessed August 10, 2022. https://www.ncbi.nlm.nih.gov/books/NBK531496/
3. Wong SS, Edwards C, Marks R. A study of white dermographism in atopic dermatitis. J Dermatol Sci. 1996;11(2):148-153. doi:10.1016/0923-1811(95)00436-x
4. Wong RC, Fairley JA, Ellis CN. Dermographism: a review. J Am Acad Dermatol. 1984;11(4 Pt 1):643-652. doi:10.1016/s0190-9622(84)70222-2
5. Mecoli CA, Morgan AJ, Schwartz RA. Symptomatic dermatographism: current concepts in clinical practice with an emphasis on the pediatric population. Cutis. 2011;87(5):221–225.
6. Soter NA, Kaplan AP. Urticaria and angioedema. In: Freedberg IM, Eisen AZ, Wolff K, Austen KF, Goldsmith LA, Katz SI, eds. Fitzpatrick’s Dermatology in General Medicine. 6th ed. Mc Graw-Hill; 2003:1129-1143.