Symptomatic dermographism: Natural history, clinical features, laboratory investigations and response to therapys

Abstract

Fifty patients with a history of symptomatic dermographism were investigated. The mean age of onset was 25·75 years (range: ‘from birth’ to 52 years) and the peak age of onset was in the second and third decades. The mean duration at last follow-up was 5–1 years (range: 3 months to 47 years). The duration was longer than 5 years in 22%, and longer than 10 years in 10% of the patients. Ninety-two percent of patients, but not a single member of an age-matched group of sixty control subjects, produced measurable wealing at a pressure of 3·5 × 105 Pa or less applied with a calibrated dermographometer. The incidence of the atopic diathesis was not increased in patients with symptomatic dermographism, and no associations with systemic diseases, food allergens or medications were established- Routine haematological, biochemical, microbiological and intradermal screening tests were not found to be helpful in the management of this condition. Protease inhibitor profiles revealed a significant reduction in the level of circulating a i-antitrypsin inhibitor which was not the result of a genetic difference between the patient and control groups. In a double-blind randomized controlled trial of eight different antihistamine regimes in twelve patients, a combination of hydroxyzine (10 mg qds) and cimetidine (400 mg qds) proved significantly superior to all other treatments in reducing dermographometer-induced wealing, and was associated with fewest side-effects.