Science

AAAAI 2017

Day 2 Summary

Day 1 Summary

By Dr. Brian Schroer

It was a great morning of lectures before the final afternoon session titled, “Practical Application of Food Allergy Prevention for Medical Providers.” The session was moderated by Dr. Andrew Bird from University of Texas Southwestern Medical Center in Dallas and presented by Dr. Scott Sicherer from Jaffe Food Allergy Institute at Mount Sinai in New York, Dr. David Fleischer from Children’s Hospital Colorado and Marion Groetch, MS RD, head dietician from Jaffe. They are some of the authors of the recent NIAID guidelines. It was a packed audience of doctors who are willing to help perform office-based challenges when necessary with the goal of preventing peanut anaphylaxis in kids who are at high risk for developing peanut allergy. 

While treatment is a major goal for doctors, an even greater goal is to prevent disease. However, for many allergies there are no easy ways to prevent them. That was what made the original LEAP findings so remarkable. It flipped conventional wisdom on its head and gave some guidance on how to prevent severe life threatening peanut (and likely other food) allergy. Now the hard work begins – how to safely perform challenges in the office. This session was set up to help doctors feel comfortable doing these challenges in very young people. 

 One of the biggest problems with food allergy throughout the years is the lack of doctors who are willing and able to take on the risk of performing in office food challenges. You know this already. How long does it take to get an appointment for food challenges at your allergist’s office? My waitlist is too long and getting longer. The real problem is that not enough doctors feel comfortable doing the challenges. The result – because of the high rate of false positives with skin and blood allergy testing, many kids are told they are allergic when they are not. If you are not allergic, then OIT, SLIT, the patch, etc. are unnecessary and are a waste of time and money. 

Dr. Sicherer started the session by reviewing who should be challenged. This was based on the new NIAID Addendum Guidelines for the prevention of peanut allergy in the United States (www.niaid.nih.gov/sites/default/files/peanut-allergy-prevention-guidelines-clinician-summary.pdf).

I will not get into the fine details here – that is the job of your allergist or pediatrician. But quickly, if kids have egg allergy and severe eczema, which is requiring frequent medications, then they should have skin testing done before peanut introduction. This should occur between 4-6 months of age or older if not done sooner. What about blood testing? Blood testing is okay if skin testing is not readily available, but has many more false positives. If the child’s skin test is negative or small positive, or if blood testing is negative at <0.35, those kids should eat safe forms of peanut containing foods at home. All other kids whose test is positive, but not too large should be considered for an in-office food challenge. 

Question: What if the child has milk or other food allergies? Though the guidelines do not say it, it was clear they recommend doing the LEAP protocol for kids with any food anaphylaxis. 
One major point he made is that the skin testing used in the LEAP trial was a lancet which may produce SPT that are different sizes simply due to the method of testing. 
Once a skin test is done and a challenge in the office is deemed necessary, the challenge should be done quickly. The longer you wait, the more likely the child may become allergic before the challenge. In our office, we try to do the skin testing and the challenge the same day. 

What about safety? Dr. Sicherer showed data that in LEAP and other studies, severe anaphylaxis to peanut is rare in this age group. This is an important point for parents and the doctors in the audience. More people will feel comfortable challenging kids with positive skin testing if the risk for a life-threatening reaction is very low. They noted that no fatalities from food challenges have been reported in kids of this age either in food challenge settings or from first time exposure to foods at home. 
He went on to discuss the obvious – parents who have an older sibling with a peanut allergy are going to be nervous and may not want to do the challenge at home. That is fine then they should be offered an in-office challenge. I tell my patients, “I’d rather you give them peanut in my office than not give them peanut at all.”

Dr. Fleischer went on to detail the equipment that doctors should have available in the office. This part of the talk did veer into the conservative realm. Just after saying how safe the challenges are in general, Dr. Fleischer discussed having the quick availability of infant-sized resuscitation equipment and the ability to give IV fluids if a severe reaction occurs. While I agree, I felt that this was counterproductive. Even I was slightly scared after this discussion and I have emergency services downstairs from my office. I appreciate that it is better to be cautious; however, I think that making these challenges available to more kids will lead to less peanut allergies and less severe reactions throughout a lifetime. 

My thoughts are that any doctor who does allergy shots should feel comfortable doing an in-office challenge. If a doctor does not know how to treat anaphylaxis in babies, they should not be seeing babies as patients. PALS (Pediatric Advanced Life Support) classes are available. Epinephrine works. 

Finally, Dr. Fleischer pointed out that 2.8% of kids who pass an in-office challenge go on to have reactions to the peanut at home. Most do not require epinephrine. I do tell my patients it is possible something will happen at home that day or in the future. Early peanut introduction is not 100% effective. If at any time the child has a reaction, then stop the peanut and call me. Which, really, is what any parent should do with any food. 

Ms. Groetch, RD noted practical issues with feeding forms of peanut to babies between 4-6 months. Normally babies lose their gag reflex between 3-7 months old. This means some kids will not be able to eat the peanut foods safely at 4-6 months. A tongue thrusting motion when a spoon enters the mouth is a good sign they are not ready. She rightly points out that the child’s parents are experts in whether their baby is ready to introduce solids. Most allergists agree with the guidelines recommendation that the babies should introduce an iron containing baby food before eating peanut. Finally, she points out data showing that peanut is a good nutritional food for babies with high levels of protein, good fats and fiber.

As with most academic sessions, some of the best information came during the question and answer session at the end. This is mostly because people ask the questions to which nobody has good answers. 

Question: Would you do blood testing before the challenge if the skin testing was positive, but warrants a challenge? Answer: Why do a test when it will not or should not change what you do. (My favorite reason to not do tests when patients ask for them.)

Question: Would you do the challenge if the blood test to whole peanut is negative, but the peanut components are positive? Answer: See above. They basically said there really is no reason to do component testing at this age. These kids do not have birch tree allergy. They have not lived through a few tree pollen seasons. This gets to my experience. In my clinic, I rarely order component testing… because it will not change what I do. But many parents request for their doctors to order component testing with every blood draw. Even when the diagnosis is clear. In babies, it is just a waste of money if they have never had a reaction to peanut yet.

Question: Are we medicalizing food introduction? Answer: We wrote the guidelines based on data from LEAP. So, it is as evidence-based as possible. In my opinion, while this is true, the answer is that we are medicalizing food introduction. I highly recommend the linked article that discusses this controversy at a higher level (http://jamanetwork.com/journals/jama/fullarticle/2603418). 

Question: If we are doing the early and often introduction to prevent peanut allergy, should we be doing this with tree nuts? Answer: We have no data. But use your judgment. They pointed out that previous recommendations to avoid foods until a certain age were rescinded in 2008. 

Question: If we are skin testing before peanut, should we also be skin testing before tree nuts? Answer: We do not want to medicalize this process of food introduction. In my practice, I do my best to make parents comfortable introducing other high risk foods at home. If they do not feel comfortable, okay, then let’s skin test and then challenge if necessary. But the slippery slope is already there. If you do peanut testing, then the next step is tree nut testing, fish, shrimp, sesame, chickpea, soy, wheat, milk… It cannot go that direction. 

Question: If a child passes the challenge, do they really have to eat the peanut three times per week? Answer: We do not know. But the consensus recommendation, with which I agree, is to tell the parents, “Eat it early, eat it often.” Do what is comfortable for you. Do not create anxiety that the parents are “failing” if they are not able to give their kids a form of peanut three times per week. 

I will be posting updates from AAAAI17 Day #2 soon. Stick around. The big food allergy day is Sunday. Remember, the work and information presented here was supported by money to do the studies. LEAP was partially funded by patient advocacy groups and through your charity. Please consider supporting EAT as a way of continuing to fund these important research studies. 

Brian Schroer, MD

3/3/17

Welcome to AAAAI17

By Dr. Brian Schroer

I am in Atlanta for EAT reporting on this year’s major allergy meeting. This is where most cutting-edge research is presented to the academic and clinical allergists. It is good to be surrounded by amazing people who have dedicated their careers to searching for the causes and treatments of allergic disease, including food allergies. While I am here, I hope to explain the new science in a way that everybody can understand.

Scientific meetings are made up of a few different venues. One is didactic style panel lectures with speakers who summarize old findings and sprinkle that knowledge with recent updates. The new research is either published in journal articles the week before the meeting or in poster or oral abstract format. Therefore, the information I present will come from both sources.
Day 1: There are no posters today, so this morning I attended the most relevant session dedicated to food allergies – New Concepts on the pathogenesis and treatment of Atopic Dermatitis.

Wait, atopic dermatitis? How is that relevant? It is immensely relevant because kids who have atopic dermatitis, a.k.a. eczema, are much more likely to develop food allergies. Many parents will remember the dry skin and itchy rash which preceded eating solid foods. Those kids are the most likely to develop anaphylaxis to foods.

Dr. Lisa Beck, a dermatologist from University of Rochester in New York, and Dr. Donald Leung from National Jewish Health in Denver, Colorado both presented old and new data showing that the skin barrier in kids with eczema is not as effective as kids who do not have eczema. This leads to increased dry skin due to higher water loss through the skin. The barrier is defective due to many factors. They described the genetic factors, including filaggrin mutations. Filaggrin mutations are more common in people of northern European descent. This allowed our ancestors to absorb the sunlight necessary to activate vitamin D. The consequence of this is kids in our modern environment are now more susceptible to developing eczema.
The other factor Dr. Beck touched upon is that kids with eczema have more Staph aureus bacteria living on the skin. It is both a consequence and a cause of the eczema. This means that the bacteria are there due to the defective skin barrier, but they also contribute to the inflammation that causes the rash in eczema. It, in turn, worsens the barrier function. Therefore, the rash in kids, which often starts at a very young age, is mostly due to the dry skin from water loss and bacteria on their skin. She also presented interesting data showing that bleach baths, which work well for kids with severe eczema, do not work by killing the bacteria or Staph aureus, but by improving the skin barrier function. However, we still do not know how it does this.

Dr. Gideon Lack, professor of allergy at King’s College in London, presented data from the LEAP (Learning Early About Peanut, NEJM 2015) study. Most of the information that he presented was consistent with the previously published findings of LEAP. LEAP proved that introduction of peanuts to kids at high risk for peanut anaphylaxis decreases the risk of becoming allergic to peanut. He discussed the important fact that eczema contributes to food allergy. It is kids who have eczema who need to somehow be prevented from becoming severely allergic to foods. He emphasized that in most kids who have eczema, who are eating a food without anaphylaxis, there is no reason to avoid that food to help treat the eczema. It does not usually make the eczema better and it may inadvertently increase the risk that they will become allergic with anaphylaxis when the food is reintroduced.

Dr. Lack additionally presented interesting data about the siblings of the patients who were randomized to eating peanuts early and often. In their study, the older children who had been tolerating peanut and eating it frequently often had younger siblings who were not in the study. There was another group of children who were not eating peanut and had no peanut products in the house. A few of the younger siblings of kids who were eating peanut became allergic to peanut during the study. None of the siblings of the kids who were avoiding peanuts became allergic. This suggested that those siblings who were not ingesting the peanut were being exposed to peanut through their skin exposure through the skin, but not through their gut. Do not take that the wrong way – the solution to protecting those siblings is not to avoid peanut being in the house. The solution is to give the siblings the peanut early and often, too!

Science is a journey. For those of you looking for an amazing new breakthrough about food allergy, this may not occur this year. Or next. Science is tough. It takes time, money and hard work. And money. Much of the work never gets published because it does not find anything new. That work is important too. The fact is that all new therapies are developed in incremental steps. I will be reporting on those steps all weekend.

We need to continue to support research for food allergies. That is the mission of Ending Allergies Together – to support the scientists who will find the ways to prevent and cure food allergies. We appreciate your support along the long road to a cure.