Connections is a quarterly newsletter for primary care providers covering the latest developments and advances in medicine at OHSU. Learn about the many clinical, education and outreach resources available to you and your patients.
From the OHSU Doernbecher Children's Hospital
Shyam Joshi, M.D.
Dr. Joshi is an adult and pediatric allergist and immunologist. His main areas of research include the management of chronic urticaria, drug allergies and food allergies.
Tyler Yates, M.D.
Dr. Yates is a pediatric allergist and immunologist and the Brody Borlaug Pediatric Immunology Distinguished Scholar. He has a particular interest in immune deficiencies, asthma and food allergy.
The allergy and immunology field is rapidly changing, with significant updates in recommendations from the American Academy of Pediatrics, AAP, and other medical societies in recent years. Two important considerations regarding pediatric food allergies are:
- Early allergenic food introduction is encouraged rather than discouraged.
- Food allergy testing should be restricted to the suspected food rather than a general panel.
Early allergenic food introduction to reduce risk of developing food allergies
The AAP recommendations published in 2000 advised delayed introduction of highly allergenic foods. However, the 2015 LEAP (Learning Early About Peanut allergy) Study showed that children exposed to peanuts earlier in life had a lower rate of developing food allergy, causing a shift in approach to food introduction.
Today, there are no indications to delay introducing allergenic foods. The target window for introducing the most common allergenic foods is 4-11 months old (in an age-appropriate method). The LEAP clinical trial showed that some children are more at risk for developing food allergies than others, including patients with severe eczema and/or who have food allergic siblings. It is even more important for these subsets of patients to be introduced to allergenic foods within the window of opportunity. These children may need to have the first introduction to peanut in a controlled environment such as an allergist’s office or have a skin or blood test specifically for peanut before trying the food.
Appropriate use of food allergy testing
Reserve food allergy testing for suspicion of a specific allergen, rather than ordering a food allergy panel. These general panels can show sensitization (positive test) but patients may not have a clinical allergy resulting in people proactively avoiding these foods. Unfortunately, by avoiding the food, high-risk patients are much more likely to develop a true allergy to it. A detailed history is the most important factor in diagnosis, and it can suggest whether to order allergy testing for the suspected allergen.
Also, there is a recent explosion in “food sensitivity” tests offered by labs direct to consumer. These tests are not helpful in diagnosis and are not Food and Drug Administration approved. These services test for IgG rather than IgE, which we know from extensive research over decades does not correlate with any type of food allergy or intolerance. These tests are not clinically indicated and may do more harm than good.
The future of food immunotherapy
Food immunotherapy is an evolving concept, and immunotherapy for peanut allergy is currently under review and awaiting FDA approval. There has been extensive research on peanut immunotherapy, which is not a cure but appears to increase the amount of peanut needed to elicit an allergic reaction and/or diminish the severity of reaction when exposed to peanuts. There are still many questions about it, such as the safest way to deliver the immunotherapy (sublingually, patches, orally). When peanut immunotherapy is FDA approved, OHSU will be an early adopter.
Clinical trials for other food allergens show mixed results and are not as far along, but the outlook for egg and milk is promising.
When to refer
When referring a patient to an allergist, using the language of an “allergy evaluation” rather than “allergy testing” is helpful. As skin testing will likely be part of that referral visit, patients need to avoid any antihistamines for a week before the appointment. The following are general guidelines for referral:
- Any patient with a known food allergy.
- Any patient with a high risk for a food allergy (severe eczema, sibling with food allergy).
- Any patient who has an incomplete, puzzling or unclear history of possible allergic responses.
Stigmas and emotional issues with food allergies
Living with food allergies means navigating food labels, school and social issues. For children, there are many social and psychological problems that can come with a food allergy (isolation, exclusion, bullying, depression) as well as physical ones. Allergists can help address these issues early and provide families with tools for education and coping.
Today, there are no indications to delay introducing allergenic foods.
OHSU Doernbecher Children’s Hospital specialists are always happy to speak with you.
Please call the OHSU Physician Advice and Referral Service at 888-346-0644 with questions.
To refer a patient, please fax to 503-346-6854.