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After treating nearly 700 food allergy OIT patients, a common theme during initial office visits surrounds not just safety but the “risk of reactions” during OIT. Many parents state their child has not had anaphylaxis for years. Others will say reactions occur regularly. Some parents say their children’s allergy testing done at an outside allergist’s office labels them as “high risk” for reactions. This leaves a lot of uncertainty in the discussion.

My discussion with patients and families focuses on the TPIRC model of OIT. The comprehensive nature of analysis not only involves elaborate allergy testing. It also involves a clear evaluation of all allergic systems of the body.   These systems involve the skin, the blood vessels, the lungs, the heart, the liver, and more. It is most important to evaluate all these systems due to the involvement of these systems during different types of allergic reactions. But while all systems are critical, the lungs are one of the most important.

As a board certified pulmonologist, my bias toward excellent lung function prior to starting OIT is based on evidence. A large Australian study published in 2014 brought to light the risk factors of reactions during allergic food exposure. The study, entitled: Safety and clinical predictors of reacting to extensively heated cow’s milk challenge in cow’s milk-allergic children., sought to define the clinical “risk factors” of children allergic to milk who were about to undergo a baked milk challenge. 71 children with confirmed milk protein allergy were set to undergo a baked milk food challenge. Keep in mind the baked milk challenge is not done all at once. It is done in a graded, staged fashion over hours of time with small incremental dose increases. Of the 71 children tested, most passed (51 total, 73%). Of the 27% who did not pass, 4 children actually needed an epinephrine injection to rescue them.

This Australian group studied these 27% who did not pass by comparing them to those who passed and discovered the top “risk factors” associated with having an allergic reaction during food dosing:

  • Any history of asthma, especially asthma requiring preventer therapy (inhaled steroids, singulair)
  • IgE-mediated clinical reactions to more than 3 food groups (separate groups ie nuts, milk, peanut)
  • A history of cow’s milk reactions consistent with severe anaphylaxis

What is the take away message?

If you are considering OIT and your child has the “risk factors” mentioned above, do everything possible to control the lungs before and during treatment. The TPIRC model not only deploys state of the art lung function testing including complete body plethysmography, forced oscillation testing, exhaled nitric oxide and lung clearance index testing. The TPIRC model of OIT ensures patients undergoing OIT are maintained at a normal to super normal level of lung function.

The questions brought forth by this study need to be studied clearly in OIT patients. TPIRC and its OIT model is actively studying these clinical questions and looks forward to publishing its data in 2016.

 

Inderpal Randhawa, MD

 

Reference:

Ann Allergy Asthma Immunol. 2014 Oct;113(4):425-9. doi: 10.1016/j.anai.2014.06.023. Epub 2014 Jul 22.

 
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The Patch vs. TPIRC OIT Model: The Difference is Clear

Patch vs TPIRC OIT (2)
Phase IIB VIPES (Viaskin Peanut’s Efficacy and Safety) trial was conducted in 221 peanut allergy patients (6-55 years with 113 children, 73 adolescents and 35 adults).  The goal of the trial was to see if after 12 months of a “patch” placed on the skin daily, the patient would be able to eat more than 1000 mg of peanut protein or 10 times their baseline dose which made them have anaphylaxis.  The patch started at 50 micrograms then increased to 100 micrograms and finally 250 micrograms.  50% of the patients utilizing the highest dose patch reached the “goal” compared to 25% in the placebo group.  6% of patients dropped out.  No major adverse events were reported.  No epinephrine was used during patch treatment.

To the credit of the company, the study was conducted safely.  However, taking a closer look at the numbers, the graph above shows out of 221 patients in treatment, only half actually reached any benefit.  Of the half who reached a benefit, only a total of 28 patients were able to actually tolerate over 1000 mg of peanut protein.  The Phase III study is planned.

The arguments for the patch:

  • It is on the skin and poses little risk
  • It can be used at a young age
  • It has some effect on the immune system’s “view” of peanut protein

The arguments against the patch:

  • One year of treatment is lengthy
  • Only half the patients receive any kind of “safety” benefit.
  • Even the half who receive the safety benefit, many of them cannot eat over 1000 mg of peanut protein (or 4-5 peanuts)
  • What happens when they stop using the patch? Will just eating a certain “amount” of  peanut continue to help with protection?
  • Is there any long term immune system benefit toward tolerance?

While it looks promising, the details provide the real specifics.  Oral immunotherapy (OIT) utilizes much higher doses of peanut protein.  In fact, unique from any other model of OIT, the TPIRC model is able to treat peanut allergy patients and eventually achieve a very high dose of protein (15,000 to 30,000 mg dose) by mouth safely.  Instead of receiving treatment for one year, patients here receive treatment over 6-12 weeks.  The TPIRC model of food allergy OIT allows the ultimate dose to be safely eaten intermittently typically once every week to monthly.  By achieving these doses, the immune system food allergy profile of each patient shows dramatic shifts toward long term desensitization, clear safety, and free eating of peanuts.

 

The medical information on this site is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes. This information does not create any patient-physician relationship, and should not be used as a substitute for professional diagnosis and treatment. We expressly disclaim responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site.

 
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Our OIT Superhero

by Pujal Patel

Aanya Photo 2Aanya was born with a milk allergy. Barely a day old in the NICU, a nurse fed her cow based formula and she started projectile vomiting.  She was JUST A NEWBORN! It took us a few days to figure out that the issue was milk, not overeating! We came home with a newborn and advice to breast feed only, no milk based formula.

At 9 months old, our pediatrician asked us to ‘try’ some yogurt.  One lick resulted in full body hives, severe GI upset and fussiness for days. After being referred to an allergist, she tested positive for milk and nut allergies (we were already avoiding nuts due to her older sister who had multiple nut anaphylaxis).  We were sent home with epi pens and advice to avoid her allergens (which were everywhere!!!).

Aanya was two years old when, at the touch of chickpea chutney, she went into anaphylaxis. She had major GI distress, hives all over her tiny body, facial swelling and was struggling to breathe. I will never forget her frantically clawing at her chest with her tiny little hands. An EpiPen saved her life!

That night I knew we couldn’t keep our kids alive just by avoiding their allergens; danger lurked around every corner no matter how hard we tried. That was the darkest night but fortunately a light came on in the form of Dr. Inderpal Randhawa. I was full of hope for the first time when I walked out of our consultation appointment. After running comprehensive tests, Dr. Randhawa put Aanya on SLIT (Sublingual Immunotherapy) which greatly helped as she also had a history of asthma attacks every 3-4 weeks. Her asthma usually ended up in nebulization, steroids and lots of urgent care and doctor visits.

We then embarked on our OIT journey with milk, followed by almonds, pine nuts, pistachio, cashew, macadamia, and pecans. We will soon be working on the remaining tree nuts, peanuts and chickpeas!!

We cannot thank Dr. Randhawa enough! We were barely surviving and now we have this new life, full of freedom, just like childhood should be!! He is our SUPERHERO!!!

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It’s National Peanut Day:  Time to Understand the Anatomy of Peanuts

Why is it important in general to understand the inner “workings” of various nuts?

All nuts are composed of many components or subparts.  The most common parts are fats, carbohydrates, vitamins, minerals, water and protein.  When it comes to peanut food allergy, the protein is the most important part.

Why is knowing the subparts very important in OIT?

It is very important to know the subparts of peanuts in OIT to better understand dosing.  When a patient is able to eat one peanut, what does that really mean?  It means how much actual “food allergy molecule protein” is that child now eating.  This is particularly important when understanding the concept of safety.

For example, if a patient can tolerate 8 peanuts daily after being treated with OIT, can the patient safely eat more than 8 peanuts at any time?  The answer lies in that patient’s immune system response to OIT.  If the patient has demonstrated improved clinical markers of sensitization and clinical evidence of tolerating high doses of peanut, the question of safety is answered more scientifically.

What are the different types of peanuts?

Peanut Comparison

There are several types of “typical” peanuts in the United States.  Please keep in mind species of peanuts in China, India and Africa have different protein structures and weights than US based peanut products.  The most common US peanut is the runner peanut.  It is available at any grocery store.  Since each type has different weights, it is important to discuss the properties of these peanuts with your allergist when deciding how much of which peanut to consume during maintenance.

How much protein is in one peanut?

On average, 10 grams of peanuts are used to pass a food challenge in any standard allergy practice office.  This is deemed a “pass” for non-allergic patients.  10 grams of runner peanuts equals 18-20 peanuts daily.  However, this is the total weight of the peanuts.  How much actual protein is in the 18-20 peanuts?  It depends on whether the peanuts are heavily roasted or not roasted at all.  If it is unroasted, the protein count ranges from 5-6 grams.  If it is heavily roasted, it can range from 4-6 grams.

Of greater interest is what amount of protein actually contains the high anaphylaxis risk epitope sequences of Ara h1, Ara h2 and Ara h3.  Early experiments to purify this protein resulted in some approximations of the dosing.  However, an exact amount of how much of these epitopes is unclear.  The likely percentage ranges from 5-15% of the total protein is comprised of the high risk sequences.

Why do the number of maintenance peanuts matter?

Based on the last question’s response, everyone’s immune system responds to peanut protein differently.  Some may respond very quickly to OIT and their maintenance dose can be 20 grams every month in order to successfully maintain a “sensitized” immune system.  However, others may need to eat 10 grams every day to maintain the same sensitization.

Again, the anatomy of the peanut is important.  It contains complex subparts of which the protein is most important.  Specific epitopes of the protein are of even greater importance for food allergy dosing and safety.  One goal of research at The Translational Pulmonary & Immunology Research Center (TPIRC) is to better study and define the anatomy of peanut protein responsiveness in order to fine tune each patient’s maintenance dose to ensure maximal safety and simultaneously ensure maximal long term benefit.

Inderpal Randhawa, MD

Chief Medical Officer, TPIRC

 

References:

U.S. Department of Agriculture, Agricultural Research Service. 2013. USDA National Nutrient Database for Standard Reference, Release 25.

10.4049/​jimmunol.169.2.882.  The Journal of Immunology July 15, 2002.  vol. 169  no. 2  882-887

 

The medical information on this site is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes. This information does not create any patient-physician relationship, and should not be used as a substitute for professional diagnosis and treatment.

We expressly disclaim responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site.

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Back to School on Oral Immunotherapy:  Prevention is Key!

by Dr. Inderpal Randhawa, M.D.

Food Allergy FullSizeRender

After treating nearly 600 patients with oral immunotherapy for nearly a decade, I am often asked what worries me the most.  From a parent’s standpoint, I would imagine the anticipated response will be a severe anaphylactic reaction during a visit updose/challenge or a severe reaction at home.  However, I believe in security during OIT.  Hence, the hospital based therapy and food challenges.  Similarly, the dosing protocols which limit the risk of a significant reaction to under 1 percent.  So what worries me the most with OIT?  The month of September.

September is back to school month.  After a predictable summer, the children on OIT now return to a bastion of bacteria, viruses, pollutants and more.  This is fodder for the immune system to react to.  It is most common, in my experience, to see a surge of mild reactions during home based therapy in September.  My advice is the same every year.  Prevent what you can and notify your physician prior to any OIT dosing if you see any signs of infection or increased inflammation.

The most common illnesses in September include:

  • Viruses (simple to complex colds)
  • Wheezing/Bronchitis
  • Sinusitis
  • Pharyngitis (strep throat)
  • Otitis media (ear infections)
  • Skin infections (pustules)
  • Gastroenteritis (diarrhea/vomiting)
  • Conjunctivitis (eye/eyelid infection)

What can you do to prevent a difficult September for your child?

  1. Lots of handwashing
  2. Use a safe nasal washing system after school daily
  3. Talk to the school teacher about sanitizers, wipes, and handwashing for all children
  4. Enforce the sick child policy (so sick children are sent home)
  5. Obtain a lung function test prior to school starting to ensure maximum lung function
  6. Monitor and limit activity on high pollution days
  7. Ensure your child’s technique for inhalers and nasal sprays is correct
  8. Avoid unnecessary visits to high risk areas (busy grocery stores, daycares, etc.)
  9. Apply the wash and change routine to all children and adults in the home. Many studies show the most common carrier of viral and bacterial pathogens are adults and older children.  The first thing to do when you get home?  Change clothes and wash down (hands, arms, neck, and face) with soap and water.
  10. Ensure a healthy classroom (refer to the American Lung Association healthy classroom checklist).

As always, if your child is ill during OIT, notify your doctor immediately PRIOR to dosing. 

Hopefully this September will be a smooth transition for all OIT patients.  Stay healthy!

 
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