40 children aged from 1 to 8 years with failure to thrive, suspected of food allergy were examined. In the small intestine biopsy, normal mucosa or atrophy of intestinal villi of various intensity were found. Eosinophilic infiltration in the submucosa was present. In children over the 3rd year of life, "prick" skin test was performed, confirming polyallergy. Total IgE level was tested in all patients but only in 25% of children was it elevated.