The term dermographism (or dermatographism) literally means writing on the skin. Firm stroking of the skin produces an initial red line (capillary dilatation), followed by an axon-reflex flare with broadening erythema (arteriolar dilatation) and the formation of a linear wheal (transudation of fluid/edema); these events are collectively termed the triple response of Lewis.
An exaggerated response to this constitutional whealing tendency is seen in approximately 2-5% of the population and is referred to as dermographism. In a minority of people, it is accompanied by itching (symptomatic dermographism).
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Dermographism urticaria. Courtesy of Professor Raimo Suhonen and DermNet New Zealand (http://www.dermnetnz.org/assets/Uploads/reactions/s/dermographis....
Dermographism should be distinguished from other types of urticaria. See the following articles:
The exact mechanism of dermographism remains uncertain. Trauma may release an antigen that interacts with the membrane-bound immunoglobulin E (IgE) of mast cells, which release inflammatory mediators, particularly histamine, into the tissues. This process causes small blood vessels to leak, allowing fluid to accumulate in the skin. Other mediators that may be involved are leukotrienes, heparin, bradykinin, kallikrein, and peptides such as substance P.
Symptomatic dermographism is usually idiopathic, though it may have an immunologic basis in some patients. Passive transfer of the dermographic response with IgE- or immunoglobulin M (IgM)-containing serum has been reported, but no allergen has been identified.
Symptomatic dermographism may be triggered by drugs (eg, penicillin), an insect bite, Helicobacter pylori infection, or an infestation (eg, scabies, Fasciola hepatica). Congenital symptomatic dermographism has been described as the first sign of systemic mastocytosis.[1]
Approximately 75% of patients with hypereosinophilic syndrome, which has multisystem involvement and high mortality, have dermographism. Psychological factors and a history of stressful life events have been implicated as triggering factors in 30% of patients.[2] However, a small prospective study showed no alteration in dermographic reaction after social stress provocation tests.[3]
One case report describes symptomatic dermographism secondary to trauma from a coral reef.[4] Symptomatic dermographism may be a presenting feature of dermatomyositis.[5]
Dermographism is the most common of the physical urticarias and can occur with other forms of urticaria. An increased incidence has been reported during pregnancy (especially in the second half), at the onset of menopause, in atopic children, and in patients with Behçet disease.[6]
Dermographism can appear in persons of any age but is more common in young adults; the peak incidence is in the second and third decades. Whether a sexual variance in prevalence occurs is unclear. None has been consistently reported, though one study on dermographism in children reported a female predominance.[7] No racial variance in prevalence is known.
Simple dermographism is the most common variant, and patients with this form are asymptomatic. However, other forms are associated with pruritus, and this can significantly affect quality of life. Most people with dermographism are otherwise healthy. An association with thyroid disease has been described in some patients but remains controversial.
The natural history of symptomatic dermographism is unpredictable. It may last for months or years, or be present intermittently. In many patients, the condition gradually improves and clears after several years. Of the chronic urticarias, symptomatic dermographism appears to have the best prognosis in terms of clearance after 5 years (36%) and 10 years (51%).[8]
Reassure patients about the benign nature of the disorder, and inform them of the possible prolonged course. Explain the adverse effects of antihistamine therapy. In particular, warn patients about drowsiness, which is especially problematic when they are driving or handling machinery.
For patient education resources, see the Allergy Center and Skin, Hair, and Nails Center, as well as Hives and Angioedema.
Whealing usually develops within 5-10 minutes of stroking the skin and persists for 15-30 minutes. A short refractory period after clearance of the wheal has been reported. Giant wheals can develop if deep extension of the swelling occurs. Intermediate and delayed forms of dermographism are also described. These develop more slowly and can last several hours to days.
In patients with symptomatic dermographism, the skin eruption is associated with itching, which is often most severe at night. Symptoms can be aggravated by heat (eg, from a hot bath), minor pressure (eg, from scratching, from friction with clothes, or from rubbing with towels), exercise, stress, and emotion.
Itching and whealing can affect all body surfaces, but the scalp and genitalia are less frequently involved. However, dyspareunia and vulvodynia have been reported in patients with symptomatic dermographism.[9] Rarer forms of dermographism include the following:
Red dermographism – Repeated rubbing induces small, punctate wheals that are more prominent on the trunk than on the limbs; this form is possibly associated with seborrheic dermatitis
Follicular dermographism – Transitory, discrete, follicular, urticarial papules occur against a bright erythematous background
Cholinergic dermographism – A large erythematous line studded with punctate wheals similar to those of cholinergic urticaria (ie, wheals smaller than those of classic urticaria and surrounded by large areas of macular erythema) is seen; purpura may be noted in severe cases; this form can be associated with cholinergic urticaria
Delayed dermographism – Approximately 3-8 hours after the immediate dermographic response, a deep, tender, burning wheal returns to the same site and persists for up to 48 hours; this form is recalcitrant to conventional therapy and is closely related to pressure urticaria
Cold-precipitated dermographism – One case report has been published[10]
Exercise-induced dermographism
Familial dermographism – One case report has been published; this form is probably inherited as an autosomal dominant trait[11]
The results from hematologic and biochemical screening tests are normal. In some patients, an increase in blood histamine levels is seen after experimental scratching.
The diagnosis of dermographism is usually made by observing the clinical response after using moderate pressure to stroke or gently scratch the skin. The site is important because areas protected from regular pressure and environmental influences (eg, the back) typically are more reactive than more exposed areas (eg, the buttocks and limbs).
A dermographometer (spring-loaded stylus) can be used to apply graded, reproducible pressure (eg, 3600 g/cm2) and record skin responses. The use of this instrument is mostly limited to research settings.
Biopsy specimens show dermal edema with a few perivascular mononuclear cells.
Dermographism can be distressing but is not life threatening. Patients with simple dermographism are asymptomatic and require no therapy. Patients with symptomatic dermographism should be treated until the problem is adequately controlled or resolved.
Recognition of the problem, avoidance of precipitating physical stimuli, reduction of stress and anxiety are important factors in medical care. In addition, scratching because of dry skin can be reduced through good skin care and the use of emollients.
Pharmacologic therapy
H1 antihistamines are the drugs of choice; however, higher-than-standard doses (up to 4-fold) are often required to achieve symptom control. In some patients, a combination of 2 antihistamines may be required. Sedating antihistamines such as hydroxyzine can be helpful. Regular treatment may have to be continued for several months. In a self-reported questionnaire of patients taking H1 antihistamines,18 (23%) of 79 were completely free from symptoms, 39 (49%) of 79 had a marked improvement, and only 3 (4%) of 79) reported no effect.[14] The addition of H2-receptor antagonists appears to result in little symptomatic benefit, although some studies have shown a further small reduction in the whealing response.[15]
Omalizumab, a recombinant humanized monoclonal antibody against immunoglobulin E (IgE), has been successfully used in patients with physical urticaria, including symptomatic dermographism. A 2018 review of the medical literature identified seven publications on omalizumab use in 54 patients with symptomatic dermographism.[16] A phase 2 placebo-controlled trial involving 55 patients showed that 72% of patients treated with 150 mg omalizumab and 58% patients treated with 300 mg omalizumab compared with 32% of placebo-treated patients improved at least 4 points in the Dermatology Life Quality Index (DLQI) scale, representing minimal clinically important difference.[17]
Adverse events appear generally low, with omalizumab being well tolerated by most patients, including children. Some patients have reported complete symptom resolution within days after the first injection.[18] Omalizumab was successfully used in a woman with three subtypes of chronic urticaria, including symptomatic dermographism.[19] Treatment was continued throughout the patient's pregnancy without any complications or obvious adverse effects, although the frequency of injections had to be increased to every 15 days.
Reinitiation of omalizumab treatment after relapse of disease appears to result in rapid and complete symptom control again after the first injection within the first 4 weeks, and no relevant adverse effects have been reported.[20]
Light therapy
Narrowband ultraviolet (UV)-B phototherapy and oral psoralen plus UV-A light therapy have both been used as treatments for symptomatic dermographism. Subjective relief of pruritus and whealing and objective reduction of wheals have been reported.[21] However, the improvement is short-lived, and most patients relapse within 2-3 months of completing phototherapy.
The goals of pharmacotherapy are to reduce morbidity and to prevent complications. Antihistamines are the mainstay of pharmacologic therapy for dermographism urticaria.
Clinical Context:
Cetirizine forms a complex with histamine for H1-receptor sites in blood vessels, the gastrointestinal (GI) tract, and the respiratory tract.
Clinical Context:
Desloratadine is a long-acting tricyclic histamine antagonist that is selective for H1 receptors. It relieves nasal congestion and alleviates the systemic effects of seasonal allergy. It is a major metabolite of loratadine, which, after ingestion, is metabolized extensively to the active metabolite 3-hydroxydesloratadine.
Clinical Context:
Levocetirizine is an H1-receptor antagonist, an active enantiomer of cetirizine. It is a second-generation prescription antihistamine.
Clinical Context:
Fexofenadine competes with histamine for H1 receptors in the GI tract, blood vessels, and the respiratory tract, reducing hypersensitivity reactions. It does not sedate.
Second-generation antihistamines, also known as less-sedating or low-sedation antihistamines, produce less sedation than traditional H1 blockers because they are less lipid-soluble and only cross the blood-brain barrier in small amounts. They also have longer half-lives, allowing less-frequent dosing.
Antihistamines act through competitive inhibition of histamine at the H1 receptor, the H2 receptor, or both. This action mediates wheal and flare reactions, bronchial constriction, mucus secretion, smooth muscle contraction, edema, hypotension, central nervous system (CNS) depression, and cardiac arrhythmias.
Clinical Context:
Hydroxyzine is a sedative antihistamine that also has an anxiolytic effect. It antagonizes H1 receptors in the periphery. It may suppress histamine activity in the subcortical region of the CNS.
First-generation antihistamines compete with histamine at the tissue-receptor level, preventing it from carrying out its mediator functions in urticaria.
Antihistamines act through competitive inhibition of histamine at the H1 receptor, the H2 receptor, or both. This action mediates wheal and flare reactions, bronchial constriction, mucus secretion, smooth muscle contraction, edema, hypotension, central nervous system (CNS) depression, and cardiac arrhythmias.
Clinical Context:
Omalizumab, a recombinant humanized monoclonal antibody against immunoglobulin E (IgE), has been successfully used in patients with physical urticaria, including symptomatic dermographism. It is administered subcutaneously at an initial dosage of 150 mg/mo, but the dosage can be increased to 300 mg/mo. Some patients have reported complete symptom resolution within days after the first injection.
Omalizumab (Xolair) is a recombinant DNA-derived humanized immunoglobulin G monoclonal antibody that binds selectively to human immunoglobulin E on the surface of mast cells and basophils. The drug reduces mediator release, which promotes an allergic response.
Simone Laube, MD, MRCP, Consulting Staff, Department of Dermatology, Lauriston Building, Scotland
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Celgene.
Chief Editor
Dirk M Elston, MD, Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina College of Medicine
Disclosure: Nothing to disclose.
Acknowledgements
Paul Krusinski, MD Director of Dermatology, Fletcher Allen Health Care; Professor, Department of Internal Medicine, University of Vermont College of Medicine
Paul Krusinski, MD is a member of the following medical societies: American Academy of Dermatology, American College of Physicians, and Society for Investigative Dermatology
Disclosure: Nothing to disclose.
Shyam Verma, MBBS, DVD, FAAD Adjunct Clinical Assistant Professor, Department of Dermatology, University of Virginia, State University of New York at Stonybrook, Penn State University
Shyam Verma, MBBS, DVD, FAAD is a member of the following medical societies: American Academy of Dermatology
Disclosure: Nothing to disclose.
Richard P Vinson, MD Assistant Clinical Professor, Department of Dermatology, Texas Tech University Health Sciences Center, Paul L Foster School of Medicine; Consulting Staff, Mountain View Dermatology, PA
Richard P Vinson, MDis a member of the following medical societies: American Academy of Dermatology, Association of Military Dermatologists, Texas Dermatological Society, and Texas Medical Association
Disclosure: Nothing to disclose.
Elsbeth Young, MD, FRCP Consulting Staff, Department of Dermatology, Amersham Hospital and Wycombe General Hospital, UK
Grattan CEH, Kobza Black A. Urticaria and mastocytosis. Burns DA, Breathnach SM, Cox N, Griffiths C, eds. Rook's Textbook of Dermatology. 7th ed. London, England: Blackwell Science; 2004. Vol 3: 47.1-47.37.
Dermographism urticaria. Courtesy of Professor Raimo Suhonen and DermNet New Zealand (http://www.dermnetnz.org/assets/Uploads/reactions/s/dermographism2.jpg).
Dermographism or skin writing on forearm.
Appearance of the word "Dermatographia" on a human arm 15 minutes after the letters have been traced with a blunt object on the skin. A type of urticaria or "hives", also known as dermatographic urticaria, dermatographism, or "skin writing".
Dermographism urticaria. Courtesy of Professor Raimo Suhonen and DermNet New Zealand (http://www.dermnetnz.org/assets/Uploads/reactions/s/dermographism2.jpg).
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