Updated guidelines from the National Institute of Allergy and Infectious Diseases for the early introduction of peanut-containing foods to children at increased risk for peanut allergies are on the horizon, pending final approval.
“Two studies recently showed that infants at high risk of developing peanut allergy [infants with egg allergy and or severe eczema] were much less likely to have peanut allergy at age 5 years if they were able to incorporate peanut regularly into the diet between 4 and 11 months of age,” said Dr. Scott H. Sicherer, the Elliot and Roslyn Jaffe Professor of Pediatrics, Allergy and Immunology, and chief of the division of allergy and immunology in the department of pediatrics at the Icahn School of Medicine at Mount Sinai, New York.
“However, adding peanut to the diet at this age requires caution because these infants may already be allergic to peanut, and so allergy testing and care in adding peanut to the diet with medical supervision is needed in this high-risk group,” noted Dr. Sicherer, a member of the expert panel that worked on the guidelines.
The draft guidelines include 43 clinical recommendations for the diagnosis and management of food allergies in children, according to the NIAID website. In particular, the draft guidelines recommend introducing peanut-containing foods to infants aged 4-6 months who are at increased risk for peanut allergy because of severe eczema and/or egg allergies, after an evaluation with skin prick testing or peanut-specific IgE testing.
“Peanut allergy is relatively common and often persistent, and so a strategy that could prevent the allergy is very important,” Dr. Sicherer said in an interview. “However, peanut can be a choking hazard as peanuts or peanut butter, and so families should talk to their pediatrician about how and when to incorporate peanut into the diet, and whether allergy testing and referral to an allergist is needed.”
Support for the guidelines comes from several large studies with promising results, notably the LEAP (Learning Early about Peanut Allergy) trial. A recent extension of that study, known as LEAP-On (Persistence of Oral Tolerance to Peanut), showed that regular consumption of peanut-containing foods from infancy to 5 years provided ongoing protection against allergies, even 6 years after peanut consumption was discontinued for a 1-year period in 550 children (N Eng J Med. 2016 Apr 14;374:1435-43).
In the original LEAP study, 640 infants aged 4-11 months with severe eczema, egg allergy, or both were randomized to dietary peanut consumption or avoidance (N Engl J Med. 2015 Feb 26;372:803-13). The prevalence of peanut allergy at 5 years of age was approximately 2% in the peanut-consumption group, compared with 14% in the peanut-avoidance group.
Another significant randomized trial, the EAT study (Enquiring About Tolerance) tested not only peanut, but also the early introduction of cooked egg, cow’s milk, sesame, wheat, and fish to 1,303 infants aged 3 months and older in the general population. The study’s strict protocol made adherence difficult, but researchers found a significant 67% reduction in the prevalence of food allergies at age 3 years among the children who followed the protocol, compared with controls, with relative risk reductions of 100% and 75%, respectively, for peanut and egg allergies (N Engl J Med. 2016 May 5;374:1733-43).
The next steps for research should make early introduction of peanut-containing foods even more effective at allergy prevention, Dr. Sicherer noted.
“We need to learn more about how much peanut should be incorporated into the diet, how long the protein has to be kept in the diet to have the best preventative effect, and whether this strategy applies to other foods,” he said.