Bernard Cohen, MD, professor of pediatrics and dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, says new recommendations for infant exposure to peanuts to prevent peanut allergy address something many pediatricians have long suspected: Early exposure to peanuts, even in infants that have eczema, could prevent development of peanut allergy.
“Many of us were concerned about delaying exposure to all sorts of allergens, the idea being that, if kids are exposed early on, they become tolerant and do fine,” Cohen says.
The pivotal point in that thinking regarding peanut allergy came with results from the landmark Learning Early About Peanut Allergy (LEAP) trial, according to Cohen. In that study of 640 infants, aged from 4 to 11 months, with severe eczema and/or egg allergy, researchers found it was better to expose even higher risk babies to peanuts early to prevent the allergy later in life.1
The new addendum2 to the 2010 Guidelines for the Diagnosis and Management of Food Allergy in the United States: Report of the NIAID-Sponsored Expert Panel,3 includes 3 guidelines for infants at different levels of risk for developing peanut allergy—all of which take in account whether or not infants have eczema.
“We know that children with atopic dermatitis [AD] have a higher rate of developing food allergies than those without AD—with about 15% of milder AD patients having 1 clinically relevant food allergy (meaning a consistent clinical reaction, not just a positive test to food) by a few years of age, and around 40% of the more severe patients,” says Lawrence F. Eichenfield, MD, professor of dermatology and pediatrics, and chief of pediatric and adolescent dermatology, University of California, San Diego School of Medicine and Rady Children's Hospital, San Diego. Eichenfield represented the American Academy of Dermatology (AAD) on the coordinating committee for the new clinical guidelines on the prevention of peanut allergy and was a member of the expert panel. “It is important to recognize this connection, and that the xerosis and impaired skin barrier associated with eczema may allow more sensitization to allergens through the skin,” he says.
The first of the 3 guidelines focuses on infants with severe eczema, egg allergy, or both that are, therefore, believed to be at high risk of peanut allergy. To reduce the risk of developing peanut allergy, pediatricians and other healthcare providers should recommend that parents feed these infants peanut-containing foods as early as ages 4 to 6 months. Providers might elect to perform tests to help determine how to safely introduce peanuts into infants’ diets, according to the first guideline.
The second guideline recommends that infants with mild or moderate eczema can reduce their risk for peanut allergy by having peanuts introduced into their diets at about 6 months of age.
The third guideline says that for infants without eczema or food allergies, parents can freely introduce peanut-containing foods into infants’ diets.
Parents should feed infants other solid foods before peanut-containing foods in all cases, according to the guidelines.
The National Institutes of Health (NIH) sponsored the expert panel representing 26 professional organizations, advocacy groups, and federal agencies to develop the Addendum Guidelines. The panel referred to results from the landmark LEAP study, published February 2015 in the New England Journal of Medicine,1 which showed infants with severe eczema, egg allergy, or both who regularly consumed peanut-containing foods in infancy through age 5 years were 81% less likely to develop peanut allergy than infants who avoided exposure to peanuts in their diets.
“The population at highest risk is children in the first year of life with severe atopic dermatitis . . . as well as those with egg allergy. Early evaluation (with serum immunoglobulin [Ig] E screening) or referral to allergy (specifically for skin testing for peanut) is important to allow this group of patients to benefit from the tolerance that can be developed with early feeding,” Eichenfield says.
Putting guidelines into practice
The latest recommendations are to identify children in the first year of life with severe atopic dermatitis or egg allergy and to get them evaluated, so that these children can get early peanut feeding.
Eichenfield says that although children with mild to moderate eczema may be introduced to peanuts at 6 months of age or older, without any specific allergy evaluation, the introduction should generally be with dilute peanut butter. Peanuts can be dangerous, as they can be aspirated, he says.
Cohen recommends a product called Bamba, a snack made in Israel by [Osem Group], for safe exposure. Israeli news source Haaretz covered a story on Bamba on the heels of a study published in the New England Journal of Medicine suggesting Israeli children suffer from peanut allergies at one-tenth the rate of Western children with similar genetic backgrounds.4 One reason could be early exposure to peanuts by eating (and teething on) Bamba, a peanut-flavored snack considered a staple of Israeli childhood, according to the article.5
“At one point I was recommending that babies be exposed to a small amount of smooth peanut butter, but I recognize there could be some aspiration concern with that, so something like Bamba could be a lot safer,” Cohen says.
As for who should be considered as having severe eczema, Eichenfield says the expert panel used this definition: “Severe eczema is defined as persistent or frequently recurring eczema with typical morphology and distribution assessed as severe by a healthcare provider and requiring frequent need for prescription-strength topical corticosteroids, calcineurin inhibitors, or other anti-inflammatory agents despite appropriate use of emollients.”
In essence, Eichenfield says, infants with atopic dermatitis that are judged by providers to be severe and that need frequent prescription-based treatments are the targeted patients to get evaluated.
“It should be stressed that the guidelines do not suggest general food allergy testing for common foods, recognizing that both skin testing and serum IgE testing has many false positive tests, and that food avoidance based on these tests is not a very successful strategy unless children have clinical reactions to specific foods,” Eichenfield says. “The guidelines are specific in recommending evaluation for specific IgE for peanut by blood test as a screen.”
Cohen says that babies with severe eczema or a family history of anaphylaxis to peanut allergen should have their first exposures in pediatricians’ offices. “But the kids who have mild to moderate eczema, with no family history of anaphylaxis, I think it makes sense for the families to do this at home,” he says.