Delayed pressure urticaria, objective evaluation of a variable disease using a dermographometer and assessment of treatment using colchicine


Dr Frances Lawlor, Institute of Dermatology, St Thomas' Hospital, London SE1 7EH, U.K.


A randomized double-blind placebo controlled trial of colchicine in the treatment of 13 patients with delayed pressure urticaria enabled us to assess some of the variables in this disorder. We have modified a previously described method of pressure testing using a calibrated dermograph-ometer and shown a pressure induced papular dose response curve. Assessment of disease activity was based on the number of pressure weals which occurred, the size of delayed pressure induced papules using a dermographometer calibrated at 9.75 × 105 pascals for five separate time periods on the back and estimations of erythrocyte sedimentation rate and the acute phase protein levels. We have been unable to show a therapeutic effect using colchicine 0.5 mg bd for 1 week.