Dermatographia or dermatographism is a skin condition. It’s one of the most common types of inducible urticaria occurring in 2-5% of the population. Categorized under physical urticaria, the term Dermatographism means ‘Skin writing’ or ‘to write on skin’. An urticarial eruption is formed on the application of even mild downward pressure in the form of a linear wheal in the shape of whichever external force is applied. A wheal is a circumscribed dermal edema also known as welt or a hive.
Urticaria dermatographia or dermatographism urticaria can be broadly categorized as symptomatic and asymptomatic.
Symptomatic dermatographism is often associated with pruritus, stinging, prickling sensation, and erythematous wheals which is the rarer but more troublesome type of dermatographism. It is idiopathic in nature but often severe at night and aggravated by heat, minor pressure, exercise, stress and emotion, helicobacter pylori, bites, scabies, systemic mastocytosis.
An asymptomatic dermatographism is only presented with the formation of wheal in the shape of trauma-induced.
Although the exact cause for dermatographia disease is unknown, its pathogenesis involves the release of histamine from mast cells.
Although not conclusive the exaggerated biological response called, ‘ the triple response of lewis’, triggered by the mechanical trauma which releases some antigens that react with the bound IgE on mast cells. This leads to the release of histamine and other inflammatory mediators.
- The dilated capillaries produce a superficial erythematous phase
- Axon-reflex flare and sensory nerve fiber communication causes broadening erythema from arteriolar dilation
- Formation of linear wheal from fluid transudation
This is the triple response of lewis. The entire response takes about 5-10 minutes after an external stimulus.
It is known to be seen in diabetic, hyper/hypothyroidism, menopausal(onset), pregnant(mostly second trimester), or medication-related (penicillin) people. Other known risk factors associated with this condition are;
- Age: mostly in young adults, peak in the second and third decade.
- Hypereosinophilic syndrome in atopic children
- Traumatic life events and psychological co-morbidities.
- Behcet disease
- Systemic mastocytosis (Congenital symptomatic dermatographism)
Dermatographia Signs and symptoms
- Formation of erythematous wheals in the form of mechanical trauma induced on the skin even by mild stroking within 5-10 minutes. Except for a very rare type of delayed dermographism where tender urticarial lesion reappears 3 to 8 hours after the initial injury that persists up to forty-eight (48) hours
- It May or may not be associated with pruritus.
- Wheals can persist anywhere between 15-30 minutes unlike the normal triple response of lewis that subsides within 10 minutes. Deeper edemas into the dermis form larger wheals.
- Mostly seen on trunks and extremities. Very rarely on the scalp and genital area(except for dyspareunia and vulvodynia)
- Histopathologically, dermal edema with few perivascular mononuclear cells is seen.
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Rare subtypes of Dermatographism
- Red dermatographism (small punctate wheals on repeated friction, predominantly on the trunk, possible association with seborrheic dermatitis)
- Cholinergic dermographism (large erythematous line with by smaller punctate wheals surrounded by macular erythema with purpura in severe cases)
- Follicular dermographism (transitory discrete follicular urticarial papules against the bright erythematous background)
- Familial (probably autosomal dominant inheritance)
- False dermographism- Presents with similar symptoms but different mechanisms are involved. They are white, black, and yellow dermatographism. White dermatographism is caused by a blanching response from capillary vasoconstriction secondary to allergic contact dermatitis and is prevalent in atopic individuals. Black dermatographism is a greenish or blackish discoloration of the skin that occurs after contact with metallic objects. Yellow dermatographism is due to the deposition of bile pigments on the skin.
- Latex allergy mimicking symptomatic dermographia is mostly seen on hands and genital region due to physical contact of latex in gloves, contraceptives, toys, etc.
Primarily, dermographism urticaria is a clinical diagnosis. It is usually made by observing the response in the subject after using moderate pressure to scratch or stroke the skin gently. A tongue depressor is used for this purpose. The site of pressure application is of importance because of the reactiveness of areas the dorsal area or back which is protected from the external environmental influences and pressure than that of more exposed parts like buttocks or limbs. The exaggerated triple response of Lewis points to the diagnosis.
A spring-loaded stylus called a dermographometer is used to apply graded pressure and record skin responses. Its use is mostly limited to the research settings due to its reproducibility.
Hematological and biochemical screening tests are usually normal, except for few cases where increased blood histamine is recorded after experimental scratching.
Dermatographia, a benign condition, seldom governs treatment until it is symptomatic. Mostly seen in young adults this condition resolves itself after approximately five years to ten years in the majority of the cases.
Symptomatic dermatographia requires medical attention due to its presentations. It is mostly treated with antihistamines. H1 antihistamines like cetirizine, loratadine are the drugs of choice, and H2 antihistamines like diphenhydramine, hydroxyzine are combined in required cases. Omalizumab has also been considered for treatment and is under research for its efficacy. Phototherapy with Narrowband ultraviolet (UV)-B and oral psoralen plus UV-A therapy has also been advised in a few cases. Adjunctive treatment with vitamin C is also used as a dermatographia cure.
Antihistamines are to be taken under strict medical supervision only as certain activities like driving, operating heavy machinery have to be avoided.
Apart from major pharmacological therapy, prevention and avoidance of aggravating factors such as physical stimuli play a major role in controlling this condition. Good skincare and use of emollients can reduce dry skin thereby aggravating dermographia due to scratching. Wearing soft clothes, reducing stress and anxiety, and practicing yoga all play a key role in controlling this.
Dermatographia Ayurvedic Treatment
Ayurveda, the ancient medicine system of India under the broad heading of twak vikara encompasses many dermatological conditions. Udarda, a Kapha dominant condition, is mainly treated with shodhana ( bio purification procedures) and shamana aushadha ( pacificatory medicines) based on the patient. The internal medications mainly will have the quality of ushna, teekshna, Vata anulomana, and pachana. They subside both Kapha and Vata along with vimargagami pitta. Along with pathya and apathya, dietary and lifestyle modification suitable to patient and disease, Ayurveda has a potential holistic approach to dermatographia. Medicines like Haridra khanda, ardraka khanda, amrita satva, arogyavardhini vati, gandhaka rasayana, aragwadha amrutadi kashaya, dashamoola haritaki,, varanadi kashayam, ayaskriti, abhyanga with katu taila, vardhamana pippali rasayana, etc.
Although not life-threatening, dermatographism is a distressing condition. Asymptomatic dermographism requires no treatment but symptomatic dermographism should be treated till the condition is controlled or resolved. Reach out to our experts at VIMS today, for proper guidance. Our expert team of doctors from ayurvedic and modern fields of medicine is always within your reach.
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