Atopic eczema/dermatitis syndrome (AEDS) commonly often arises during early infancy. In several intervention studies a beneficial influence on AEDS course of certain intestinal bacteria, administered as 'probiotics', has been described. To evaluate the possible role of the natural intestinal microflora in children with allergic eczema/dermatitis syndrome regarding immediate type hypersensitivity to food allergens, children with food allergy (AAEDS, n = 68) have been compared with children without detectable food allergy (NAEDS, n = 25). All children (n = 93) in preschool age, mean age of 2.6 (+/-1.8) years, diagnosed with AEDS who were treated as inpatients in 2003 in a dermatological hospital were included. The correlation between fecal microflora, parasites and specific immunoglobulin E (IgE) antibodies against common food allergens was analyzed. A similar composition of intestinal microflora in children with AAEDS and NAAEDS was found. The food allergens that were most frequently detected were egg white, cow milk, casein, peanut and hazelnut. Furthermore, a significant association between IgE sensitization against important food allergens and components of the fecal microflora could not be demonstrated. With aging changes occur in the intestinal microbiota [Proteus/Klebsiella and age (rho = -0.607) and Enterococcus and age (rho = -0.428)]. In two subjects of the AAEDS group Blastocystis hominis was found. The composition of natural intestinal microflora in children with AAEDS and NAAEDS was similar. Hence, there is no evidence of a role of the intestinal microflora with regard to the development of infant (food) allergy in children with AEDS. The possible consequences for allergic diseases later in life require further investigation.