10 May 2010: Early results from a study of more than 500 infants with egg or milk allergy indicate that they are highly likely to test positive for allergic antibodies that are specific to peanuts. This unexpected finding suggests that these infants are at risk for developing peanut allergy later in life and should be evaluated by a health care professional before introducing peanuts into their diet.
The findings appear in the May issue of the Journal of Allergy and Clinical Immunology. These are the first published results from the clinical group of the Consortium of Food Allergy Research (CoFAR), a major food allergy research program supported by the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health.
Eggs, milk and peanuts are the three most common allergenic foods for infants. An infant who already has a milk or egg allergy is known to be at risk for later developing a peanut allergy. Another risk factor for peanut allergy is moderate to severe eczema (atopic dermatitis). This is the first systematic study, however, of the natural development of these three food allergies in very young children.
This observational study has enrolled infants between 3 and 15 months old. All have immunoglobulin E (IgE) antibodies to egg or milk. Some of these infants have known clinical allergy to eggs or milk, some have moderate to severe eczema, and some have both allergy and eczema. None of the infants has known peanut allergy. These infants will be followed until 5 years of age to see if their allergy to milk or eggs continues or resolves, and to see if they develop an additional allergy to peanuts.
As part of the initial assessment of the infants, the CoFAR investigators measured the level of IgE antibody to peanuts. They made two unexpected observations: More of the infants have elevated levels of IgE antibody to peanuts than the investigators had anticipated, and some of these infants have such high levels that they may already be allergic to peanuts without their parents being aware of it.
The researchers encourage parents of children with egg or milk allergy to talk to their doctor before incorporating peanuts or peanut products into their child's diet.
Article: SH Sicherer et al. Immunologic features of infants with milk or egg allergy enrolled in an observational study (CoFAR) of food allergy. Journal of Allergy and Clinical Immunology. DOI: 10.1016/j.jaci.2010.02.038 (2010).