A 20-year-old college student presents with intermittent itching of approximately 4 weeks duration. He is in good health and currently takes no oral medications. He relates treatment of a sinus infection with amoxicillin several days prior to the onset of his pruritus. Full-body examination is unremarkable and no hives are apparent. Stroking of the skin of his back elicits raised wheals.
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Dermatographism, also known as skin writing, occurs when a dull object strokes the skin and creates the shape of the strokes.1 It presents as an erythematous and edematous flare reaction. Dermatographism can cause pruritus and is induced by scratching or stroking the skin or by wearing tight or abrasive clothing. The response can appear in any age group; however, it is most common in young adults, with a peak onset in those aged 20 to 30 years.2
Underlying etiologies for dermatographism may include drug reaction, infectious agent, and systemic disease.3 The mechanism is likely stimulation of mast cells that release histamine. The histamine then causes blood vessels to leak and release fluid in the surrounding tissue, causing erythema and swelling.4
Management of dermatographism can be difficult. Treatment modalities that may prove effective include H1 and H2 receptor antagonists, leukotriene receptor antagonists, cyclosporine, oral steroid drugs, and phototherapy.5
John Pappas is a medical student at the Geisinger Commonwealth School of Medicine in Scranton, Pennsylvania. Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. He practices dermatology in Hazleton, Pennsylvania.
- Kontou-Fili K, Borici-Mazi R, Kapp A, Matjevic LJ, Mitchel FB. Physical urticaria: classification and diagnostic guidelines. An EAACI position paper. Allergy. 1997;52:504-513.
- Bhute D, Doshi B, Pande S, Mahajan S, Kharkar V. Dermatographism. Indian J Dermatol Venereol Leprol. 2008;74:177-179.
- Mecoli CA, Morgan AJ, Schwartz RA. Symptomatic dermatographism: current concepts in clinical practice with an emphasis on the pediatric population. Cutis. 2011;87:221-225.
- 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. New York, NY: Mc Graw-Hill; 2003:1129-1143.
- Heelan K, Murphy M. Symptomatic dermatographism treated with narrowband UVB phototherapy. J Dermatolog Treat. 2015;26:365-366.