Immunohistochemical Study of Intestinal Biopsies from Children with Atopic Eczema due to Food Allergy

In 18 patients with skin reactions after food challenge and in controls the numbers of immunoglobulin-containing cells in the intestinal mucosa were studied by the direct immunoperoxidase technique; IgE and C3 were studied by FITC-conjugated sera also. Serum immunoglobulins, complement fractions 3 and 4, and reaginic antibodies to the foods were measured during the provocation. None of the patients had any deficiency in the numbers of immunoglobulin-containing cells in the intestinal mucosa or in the serum immunoglobulin concentrations. The numbers of IgM- and IgA-containing cells were higher in the patients than in the controls. But patients and controls had equally low numbers of IgE-containing cells. No deposits of C3 were seen in any of the biopsy specimens. Serum IgE was increased in 13 cases. The presence of reaginic antibodies to cow's milk and cereals correlated well with the clinical reaction (12/15 and 5/7 of the cases). There was a negative correlation between the logarithm of serum IgE and the number of IgA-containing cells in the jejunal mucosa (P less than 0.01). High prechallenge counts of blood eosinophils were seen in seven cases and these showed a close correlation with the eosinophils in the jejunal mucosa (P less than 0.001).