Fecal IgE levels in infants at 1 month of age as indicator of atopic disease.

Fecal IgE levels were investigated in 165 asymptomatic infants at 1 month of age under two nutritional regimens, breast-feeding and formula feeding, and the possibility of predicting by fecal IgE levels the onset of atopic disease was studied in these infants. IgE levels were measured by time-resolved fluoroimmunometric assay. IgE antibodies are detectable in fecal extracts, and we have already reported that IgE levels are increased in food-allergy patients after administration of food allergens, and this increase in fecal IgE levels may be a specific consequence of the local immune response to food-allergen stimulation in the gut mucosa. The presence of atopic disease and the feeding method during the nursing period were surveyed by questionnaire in 89 of these 165 infants when they were 18 months old. In an analysis of the present results, IgE values above 0.015 U/ml, the lower limit of measurement, were considered to be high. Forty-eight (29%) of the 165 subjects showed a high fecal IgE level. Thirty-seven (35%) of 105 formula-fed infants had high fecal IgE levels, whereas only 11 (18%) of 60 breast-fed infants had high levels (P < 0.05). With respect to atopic family history, 30 (39%) of the 77 infants with atopic family history had high fecal IgE levels, as compared with 18 (20%) of the 88 infants without atopic family history (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)