The Method of Antigen Specific Damage of Leucocytes by Food Additives in Patients with Bronchial Asthma

Background: Diagnosis of adverse reactions to food additives is difficult due to a variety of mechanisms involved and the lack of sufficiently reliable methods for their determination. The diagnosis of an intolerance to food additives is still based only on placebo-controlled oral provocation.

Methods: The aim of this study was to determine the incidence of intolerance to ponceau 4R (E124), indigo carmine (E132), azorubine (E122), tartrazine (E102), sunset yellow (E110) and sodium benzoate (E211) among patients with bronchial asthma. We studied 114 patients with bronchial asthma using clinical and laboratory methods. Also we used the method of antigen specific damage of leucocytes by food additives. After the incubation of leucocytes with solutions of food additives to leucocytes was added 0,05 ml of trypan blue and counted the percentage of stained (damaged) granulocytes with the food dye and in control tests. If damaging leucocytes were more than 20% in comparison with controls - the test considered positive.

Results: : It was found that positive to ponceau 4R were 6 of 114 patients, to indigo carmine - 3 of 73 , to sodium benzoate - 4 of 73, to azorubine -11 of 114, to tartrazine - 7 of 114 and to sunset yellow - 9 of 114. There was a correlation between the results obtained and data history. Between experienced and control group (the patients without allergic diseases) were the reliable differences (p<0,05).

Conclusions: 1. Under influence of the food additives leukocytes of patients with bronchial asthma are damaged and painted by trypan blue.2. The method of antigen specific damage of leucocytes by food additives can be used for diagnostics of the allergies to food dyes, sodium benzoate and other gaptens.