Immunoglobulin E in feces from children with allergy. Evidence of local production of IgE in the gut.

Immunoglobulin E (IgE) was found by a double antibody radioimmunoassay technique (PRIST) in extracts of feces from 21 of 40 children with different kinds of allergy. 15 of the 22 children with gastrointestinal allergy and atopic dermatitis, but only 6 of the 17 patients with hay fever and/or bronchial asthma had detectable IgE in the extracts. The patients with gastrointestinal allergy also had the highest concentrations of fecal IgE, and the concentrations in feces did not correlate with the corresponding serum IgE levels. Furthermore, the presence of IgE in feces correlated with specific IgE antibodies in serum, measured as the sum of RAST classes to the food allergens wheat, fish, cow's milk and egg-white. IgE may therefore have been produced locally in the gut as a result of stimulation by food allergens. Since the concentrations of IgA in feces were also high in many children with allergy, and since some possibility of a positive correlation with high IgE concentration seemed to exist, the stimuli for local production of IgE and IgA may be interrelated.