Food Allergy Treatment Definitions

Peanut Allergy

As I reported last week, we've been presented with the exciting opportunity to participate in a sublingual immunotherapy program for peanut allergy. As I've begun discussing this opportunity with others, I'm finding a good deal of confusion, both within the food allergy community and beyond, about potential food allergy treatments. The two most promising possible treatments available today are sublingual immunotherapy and oral immunotherapy. Here are a few important definitions when we talk about "food allergy treatments":

Immunotherapy is the process of giving small doses of what a person is allergic to in order to increase tolerance and build immunity to reduce the likelihood of an allergic reaction

In sublingual immunotherapy (also known as SLIT) the allergic person will hold the food extract under the tongue for a short period of time (our allergist's protocol is two minutes) and then swallow it. The dose will be gradually increased over time. Our process will be one office visit every two weeks and daily doses at home at the same level between those office visits. The entire process will take place over 7 months. Following SLIT, patients may participate in a food challenge, or may be recommended for an oral immunotherapy program.

In oral immunotherapy (OIT), an allergic individual swallows a small amount of the food they are allergic to. Treatment begins with a diluted form of the food and is gradually increased during office visits and at home

There are pros and cons to any type of treatment program. I encourage anyone considering SLIT or OIT to do your own research and make the best decision you can for your family. Some will go with a wait and see approach and not take any action right now. Others will decide to move ahead in these still unchartered areas. Here are a few articles and links to get you started if you are considering either method:

Oral Immunotherapy Not Ready for Prime Time, by Dr. Hugh Sampson. In the comments that follow the article, many parents of children who have successfully gone through OIT speak out.

Is Sublingual or Oral Immunotherapy better for Treatment of Food Allergy, published in February 2012 by the American Academy of Allergy, Asthma and Immunology (AAAAI), concluded that neither are optimal. That said, at the March 2012 AAAI annual meeting, presenters offered new research about SLIT and OIT that showed promise and results for both.

It is obvious that things are moving quickly in this area. If you are considering SLIT or OIT, I encourage you to talk to your doctor, read the research and talk to other parents who have been through this. As we move through the SLIT program, I'll keep you apprised of our progress.  If you are interested in talking to someone who has been through OIT, shoot me an email (food allergyassistant@gmail.com) or leave a comment and I can get you in touch with someone.

Food Allergy Testing: Why are so Few Allergists Doing "The Gold Standard"?

Dr. Ves Dimov of Allergy Notes makes some good observations about oral food challenges (OFC) in his article, "85% of Allergists perform Gold Standard Test for Diagnosis of Food Allergy". He points out that fewer than 6% of allergists perform more than 10 per month, citing time, insurance reimbursement and risk of adverse reactions as the reasons for conducting so few OFC's.

For several years food allergic patients have been told that OFC's are the most definitive method to test food allergies. More commonly however, skin prick tests and blood tests are used by allergists to determine food allergy. Our personal experience has shown that the results of these two common allergy tests may not provide definitive results. Skin tests on a person with eczema and/or sensitive skin is often of little value. Certain people react to nearly anything pricked into their skin and the blotchy red welts that result make it appear that the person is allergic to everything.

The next test for food allergies is blood work. I remember one visit to Children's Hospital with my then 2 1/2 year old. They told us to list any food we thought he might have an allergy to. We listed 30 foods we suspected.
The blood test results? Allergic to all.

Nonsense said our primary allergist as my child had been successfully eating many of these foods. We've had many inconclusive blood test results. Not only is blood work traumatizing to a child, but avoiding so many types of foods unnecessarily could lead to poor growth and nutrition.

We've now done about a dozen oral food challenges in the allergist's office now. They are very time consuming- taking between 3-4 hours typically. This makes it difficult to do during the school year (and who wants to give up a school holiday to sit in the allergist's office to eat something that may cause an allergic reaction?). There are three types of OFC's: open, single-blind and double blind. In the open challenge, everyone knows the suspected food is being given. This is the only type of challenge we've done. A single blind means the patient doesn't know if they are ingesting the offending food or a placebo, and in the double blind, the patient and the medical staff are unaware if it is the suspected food or a placebo. We have observed a huge psychological factor in these open challenges in which the person may think there is tongue tingling or thickness in the throat because they know the food may cause a reaction. We have also found over the years, OFC's have become more and more expensive to us as insurance companies have decreased reimbursement.

So, even OFC's still may not give the definite results we seek. Some of our challenges may have been halted prematurely by the allergist who was concerned about possible reactions. Sometimes we leave the OFC still not knowing for sure if there was a reaction. For now, though, it's the best test we've got and it does provide some clues that may be helpful to the food allergic person and their family.

In light of this, I hope to see more training of allergists and better reimbursement from insurance companies. Until we come up with something better, let's use OFC's to help those with food allergies determine what foods need to be avoided and what foods they need not fear. 

Check out Oral Food Challenge Practices among Allergists in the United States from The Journal of Allergy and Immunology for more information.