We studied the stimulation of lymphocytes in 258 patients with urticaria and/or angioedema using a series of food extracts and additives. Of this group, 238 revealed a positive response index (RI). There was a positive RI to additives in 18.4% of the cases, to food extracts in 35.2% and to both extracts and additives in 46.6% of the cases. A positive RI to both aspirin and tartrazine was revealed in 25% and to all the additives tested in 11% of the cases.
Diets from which food extracts and additives were excluded achieved total remission in 159 (61.1%), partial remission in fifty-seven cases (22%) and no remission in forty-two (16.2).