Symptomatic dermographism is commonly seen in _______

Ans. B. Chronic urticaria* Dermographism is commonly elicited in chronic urticaria patients.* Simple dermographism is defined as the triple response of local erythema due to capillary vasodilatation, followed by edema and a surrounding flare due to axon reflex-induced dilatation of arterioles after stroking the skin.* However, in <5%, it is accompanied by severe itching (symptomatic dermographism or factitious urticaria).* Patients complain of swelling and itching at sites of trauma, friction with clothing or scratching the skin. The itching is usually disproportionately severe compared with swelling and is often most severe at night.* The eliciting stimulus determines the shape of the wheals, but they are often linear from scratching or stroking.* Dermographism is usually idiopathic, but may sometimes follow a drug reaction (e.g. penicillin) or an infestation, including scabies.* It may last for months or years, or be present intermittently.* The reaction is mediated by IgE and neuropeptides.Note: Cholinergic dermographism is seen in some patients with cholinergic urticaria, whose dermographic response consists of an erythematous line studded with punctate wheals characteristic of cholinergic wheals.