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Discussion Boards => Main Discussion Board => Topic started by: evergreenmom on March 27, 2014, 06:47:03 PM

Title: ara h 2 results- borderline
Post by: evergreenmom on March 27, 2014, 06:47:03 PM
Well we did the peanut protein component testing and my little guy's ara h 2 came back at .48 which they said is borderline. So I did a quick pub med search and found that ara h 2 is the most likely protein to cause anaphylaxis. So what does this result really mean for my son? I mean I guess it's good that his numbers were on the low side but since that protein tends to be more prone to reaction I feel like it's a mixed message. All other proteins- arah 1, 3 8 and 9 were negative.

Should we do a food challenge at the doctors office or should we wait it out a while longer and hope he is desensitizing but give his body a little more time before testing with a food challenge? I am glad the news seems somewhat positive but still confused... any advice???
Title: Re: ara h 2 results- borderline
Post by: twinturbo on March 27, 2014, 07:37:08 PM
What are the other data points in terms of history of reaction, trend of test results over time? You've probably shared before but if you could bear with once more here it might be a fuller snapshot inthread for computing.

I had the test done for my child who has yet to come in to any serious contact with peanut. His doctor at the time thought that the borderline number meant that the test was at least valid because it showed some sensitization meaning he had come into contact with it in trace amounts already. I should put in there that my older child is nearly PA only to our knowledge. The reason we used it for younger child is he's had multiple instances of full on anaphylaxis to most common proteins it was to see if that was one we probably needed to add to hard avoid in terms of life quality and socializing.

Phadia interpreted the results for us then we followed up with the allergist. Did either help interpret it with you? Looking further ahead do you know how the allergist would perform the challenge? Are the terms agreed upon in location, procedures, intervals, open single or double, defining a pass or calling it a reaction? Will your child cooperate with the challenge? Can he express himself? I know you said he's little.

Putting fire to my feet to come up with a direct no beating around the bush answer, if he does not have a history of anaphylaxis to traces with that low a number I'd be inclined to consider a challenge. Consider. Be a looooot of details to work through with doc particularly post-challenge protocols.
Title: Re: ara h 2 results- borderline
Post by: CMdeux on March 27, 2014, 07:37:25 PM
Well, unfortunately, your result probably means that you.... just... don't know.

I'm not sure that you'd know with as much certainty as you'd like even after a challenge-- though it might give you some peace of mind in terms of figuring out what kind of threshold he has.  At the moment, anyway.  The danger there is that in some people prone to anaphylaxis (and with peanut and some other allergens in particular-- like treenut, apparently) those thresholds are not necessarily stable in everyone-- that is, in a number of adolescent fatalities in particular, people were managing much as they ALWAYS had... and really, the ingestions that caused fatal reactions didn't seem to be all that unusual in their normal experience... until they caused a catastrophically awful reaction, that is.  Many of these were people who managed so well (had such high thresholds, that is) that they didn't even carry epinephrine any more, not having needed it in... well, in some instances, in forever.

SO.

My question for you is this-- if your child had a minor reaction during a challenge-- what would it mean?  I'd caution you to avoid assuming that future reactions would be minor, as having a (+) Arah2 seems to indicate otherwise.

If it took a teaspoon of peanut butter to do it, what would it change for you?  Anything?  If it took 1/100th that amount?

The answers to those questions might make a challenge a completely worthwhile thing for you-- they would certainly tell you something about threshold, which might give you better tools for management in a school setting, might let you feel more comfortable with restaurant and travel planning, etc.
Title: Re: ara h 2 results- borderline
Post by: twinturbo on March 27, 2014, 07:48:54 PM
Sometimes it seems like individuals with the wider thresholds on peanut take on the most risk even though they get more relative freedom. You don't know the boundaries on that electric fence as well.
Title: Re: ara h 2 results- borderline
Post by: CMdeux on March 27, 2014, 09:25:01 PM
True, 'dat...  but it is a VERY different beastie to live with a contact/aerosol sensitivity, and that only seems to come with a very low threshold dose.  So knowing that you're probably not living with that might make a challenge quite worthwhile-- the lifestyle modifications there are just, well-- so much more extreme than they are if all you really worry about is what YOU are eating, if that makes sense.

That has pretty profound implications for school and air travel, at the very least.

Of course, all of this assumes that reaction history is a virtual unknown. 

Your child was born in 2008, yes?  So that's old enough to understand the purpose of a challenge, and to communicate well during that challenge (assuming no delays that would mean otherwise).

As for whether or not to wait and see-- well, I'm not too sure that there IS a lot of allergy-specialist agreement on that one at the moment.  There's some evidence to suggest that avoidance can exacerbate an allergy that might otherwise become tolerance... er, at least "high threshold" (and therefore lower risk from accidental and unavoidable types of exposures)... and then again, there is, as you're probably aware, some evidence that suggests that some kids just need more TIME to outgrow, if they are going to...

In other words, as far as I know, this is still an open research question-- but you could run it past your doc, for sure.

Title: Re: ara h 2 results- borderline
Post by: evergreenmom on March 28, 2014, 12:47:58 PM
Thanks Twinturbo-

My son just turned six years old, so I guess he's not so little anymore! And yes he can express himself well these days... As far as history:

At age two we tried to feed him peanut butter on several occasions and he immediately spit it out each time- he didn't react so we just thought he didn't like it- he wasn't super verbal at that time so it was guess work on our part. At age 31/2 he had two peanut incidents. First one he ate some praline ice cream that we later found out had nu nuts in it- peanuts washed and re-flavored to taste like pecan. He had a horrible painful diaper rash the next day and we back tracked to the ice cream and at that point I decided not to offer him any more peanuts and to ask pediatrician at next appointment. A couple of months later we were at a friends house and he put one peanut m&m in his mouth and immediately began spitting it out and told us his tongue felt funny, a few minutes later he began making throat clearing noises and said his throat felt funny. We gave him benedryl and some cold water and within another few minutes he was fine no more funny sounds or feelings. We went to an allergist the next week and she said that we were very lucky the benedryl worked and that we needed to completely avoid peanuts and carry epi at all times. He was confirmed with skin test w/16mm weal. No reactions since then but we've been extremely careful. He also has had issues with excema though thankfully no asthma.

Recently he had his peanut IGe checked which was 0.37 and overall IGe of 280. I insisted on the component test and now his allergist wants to do a skin test followed immediately (if skin looks good) by an in office oral challenge to peanut butter. I am still not comfortable with this based on even a borderline result to ara h 2- isn't that the protein which indicates lifelong allergy? Part of me isn't feeling 100% confident in this allergist opinion- he's our second as the first had a strange personality. It makes me feel a little crazy to keep changing doctors  ??? so not sure what to do next....

Additionally, I worry that he will not want to eat peanut butter for the challenge or as ongoing therapy because we've put the fear of G_D into him for the past 2 1/2 years and also he clearly never liked the taste of it.

I am considering the challenge because if he passes and is able to incorporate peanuts into his diet and if that is successful and he doesn't re-sensitize that would be a whole new world for us- so great to not have to carry epi everywhere and always be so worried about every bite of food he takes outside of known and safe meals prepared at home.

I was hoping someone might have had a similar experience with borderline ara h 2 numbers... I haven't been able to talk in detail with the allergist yet but as I said I just have sort of a nagging feeling that he is too cavalier about the in office food challenge which he wanted to do just based on Ige levels and now told the nurse to tell me we should food challenge based on borderline ara result... I am overwhelmed and totally confused....

Thanks for all of your comments though- you gals are awesome!



Title: Re: ara h 2 results- borderline
Post by: twinturbo on March 28, 2014, 01:16:56 PM
I think though what the data is bearing out is that a pass at the office is only the beginning of post-challenge protocols and maintenance, but it's being debated depending if a child truly outgrew or had OIT or did not have a true pass. I'll dig up some threads for reading. The names that come to mind for this are aggiedog, lala, and booandbrimom. Another member whose older son just passed a peanut challenge did so with a huge wheal if I remember correctly. She used the component test which showed that he may have outgrown.

Links,etc. (member name) has some not surprisingly good links on peanut challenges and what qualifies as a pass.

Don't let any of these freak you out think of it as preparation. Sorry if it's what you already read it's what came to my mind. Links is better than I am on getting more exacting sources.

Allergy after passing peanut challenge? (http://foodallergysupport.olicentral.com/index.php/topic,6311.0.html)

Component Testing (Pt.2) - Why Should We Care? (http://foodallergybitch.blogspot.com/2012/06/component-testing-pt2-why-should-we.html)

DD's uknow peanut test results (http://foodallergysupport.olicentral.com/index.php/topic,5950.0.html)

ds doing challenge on Wed  (http://foodallergysupport.olicentral.com/index.php/topic,8429.0.html)

So, when do you just DEMAND a challenge? (http://foodallergysupport.olicentral.com/index.php/topic,8482.0.html)
Title: Re: ara h 2 results- borderline
Post by: CMdeux on March 28, 2014, 02:35:37 PM
Well, dealing with Ara h2, there's NO way that I'd consider a challenge to be anything like casual.  If you do get that sense from a doc, that's not a doc that I would schedule a challenge with, frankly.

But--

there's avoidance, and there's avoidance.  Avoiding the way that you must with a peanut allergy (rather than a possible peanut allergy, or one that you KNOW to be high-threshold dose) has some pretty substantial social, emotional, and developmental consequences.

I'd probably be keen to know, in your case.  Your child is young enough that for him-- this could be nothing more than a dim unpleasant memory relating to his preschool years in another decade.

The alternative is what some of us here are living with older children, teens, and young adults-- it really does have profound consequences, and it WILL limit his opportunities and his (and your) life in ways that probably aren't obvious at the moment.  Doing that if it's necessary is one thing, of course... but otherwise it's a bit like having your child wear a helmet everywhere because of one (possibly febrile) seizure as a toddler.    If that makes sense, I mean.

Things that are impacted when you have a life threatening food allergy:

1.  school choice
2. friends
3. teachers
4. extracurricular activities
5. travel
6. restaurants
7. every holiday
8. camp
9. summer programs
10. sleepovers
11. school field trips
12.  movies and hanging out with friends
13. sports
14.  community service
15.  church
16. independence from parents/other adults
17.  outdoor activities-- in remote or inaccessible locations
18.  fundraising
19.  high school course selection
20.  food-based activities in curriculum
21. foreign exchange
22. dating
23. college prep testing
24. college selection
.
.
.


Usually I make it a point to tell parents NOT NOT NOT to "go there" in their minds-- but the point is that those very normal things are points of difference-- sometimes PROFOUND difference-- in experience between most of our kids by young adulthood... and honestly, being different is the LAST thing that adolescents want.

That's why I would rather KNOW.  It's not that the answer will necessarily be the one that we'd all like-- but that if it's "avoid-avoid-avoid" then you know that you're doing it because you MUST.  Not because you're afraid of the unknown, but because of a fear that is completely rational and well-considered. That secure knowledge will make you a rock-solid advocate for your child-- and that certainty will be something that you'll both need throughout his life.

You'll have to ask other people to alter their behavior for your child's allergy-- will you hesitate if you're not truly sure that they have to?  I would.  Will you be willing to "fudge" a little with your tween when he doesn't want to wear a medic-alert ID?  When he doesn't want to carry his epipen?  If you're not sure that he needs to...  it might even seem pointlessly cruel to you on some level, yes?  Especially when those things make him different, when they mean that he has to endure teasing from peers... 

That's why I'd like to know, if it were me.   :heart:  But the only way that I'd be comfortable with this kind of challenge is under the care of a doctor that I felt was TOP-notch, and whom I trusted implicitly.   Maybe even then-- I'd want to do it slowly, with a lot of safety protocols in place.  Maybe even in a hospital setting. 



Title: Re: ara h 2 results- borderline
Post by: evergreenmom on March 28, 2014, 04:25:01 PM
Thanks CMdeux-

You get it exactly. I do feel the doc is a bit relaxed about this. I just don't feel super confident in his opinion and certainly not in doing the challenge in his office. I mean maybe I am  overreacting to a borderline number- I don't understand the variables- but I just feel had all numbers come back negative I could see going forward with a food challenge but as it is I just feel we don't have the info to feel confident that he'll just pass with flying colors and go forth into the world free of worry.

But you are right also what a big difference it would make to our lives if we knew for sure we didn't need to worry any more!

I am leaning towards waiting a bit longer- perhaps do another component test in 6 mos- a year and then decide?

Do any of you  now of a top allergist in Washington state?

Or is there a top allergist who is willing to answer questions via email?
Title: Re: ara h 2 results- borderline
Post by: LinksEtc on March 28, 2014, 06:29:35 PM
Quote from: twinturbo on March 28, 2014, 01:16:56 PM
Links,etc. (member name) has some not surprisingly good links on peanut challenges and what qualifies as a pass.

:smooch:

-------------------

This is the main thread that I'm putting together regarding challenges.

Oral Food Challenges - Links & General Info (http://foodallergysupport.olicentral.com/index.php/topic,8623.0.html)

I am thankful that we were able to do challenges for my dd - it's made a big difference in our lives.

As with any medical procedure, the risks/benefits have to be weighed. 

Title: Re: ara h 2 results- borderline
Post by: LinksEtc on March 28, 2014, 06:33:23 PM
Quote from: CMdeux on March 28, 2014, 02:35:37 PM
That's why I would rather KNOW.  It's not that the answer will necessarily be the one that we'd all like-- but that if it's "avoid-avoid-avoid" then you know that you're doing it because you MUST.  Not because you're afraid of the unknown, but because of a fear that is completely rational and well-considered. That secure knowledge will make you a rock-solid advocate for your child-- and that certainty will be something that you'll both need throughout his life.

Quote from: CMdeux on March 28, 2014, 02:35:37 PM
But the only way that I'd be comfortable with this kind of challenge is under the care of a doctor that I felt was TOP-notch, and whom I trusted implicitly.   Maybe even then-- I'd want to do it slowly, with a lot of safety protocols in place.  Maybe even in a hospital setting.


Yes.  Great points.
Title: Re: ara h 2 results- borderline
Post by: CMdeux on March 28, 2014, 08:28:17 PM
You might try to send a PM to Stinky and ask if she has someone she'd recommend to you-- the very well-respected allergist in the western part of the state (that I knew about) has very sadly passed away.  :/

I'd be interested in that info too, now that I think about it, as we are potentially looking to relocate in a few years, and had been considering the north sound.
Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 02, 2014, 05:46:29 PM


I found the following at Quest Diagnostics web site: http://www.questdiagnostics.com/testcenter/testguide.action?dc=TS_Peanut_Component_Panel (http://www.questdiagnostics.com/testcenter/testguide.action?dc=TS_Peanut_Component_Panel)

Unfortunately, I still don't quite know what to make of the borderline result to ara h 2  ??? :rant:

But the following (found near the end of the quest diagnostics info) posted above makes me feel a food challenge isn't the way to go at this point:

Patients with only Ara h 8 sensitization may consider taking an oral food challenge test, and, if negative, they may not have to avoid peanuts or peanut-containing foods.

I get that borderline isn't the same as a positive reaction but it isn't exactly negative either is it???

BTW there are two members that go by "stinky"... stinky 6 and stinky 10 any idea which one lives in Washington state?


info copied below:

Peanut Component Panel
 
Clinical Use
Assess risk of severe allergic reaction vs mild or localized reaction to peanut exposure
Clinical Background
The prevalence of peanut allergy in North American school-aged children is approximately 1%.1 This allergy is often a lifelong condition,2 and is the most common food-related cause of fatal allergic reactions in Western countries.3 Peanut allergy is typically diagnosed based on clinical history and peanut sensitization (ie, IgE antibody response to peanut extract during blood or skin prick testing). Sensitization, however, does not correlate with allergic symptoms in a large percentage of patients,4,5 and as many as 77% of peanut sensitized patients may not be at risk for a systemic reaction.6 This may be because most tests are based on crude natural peanut extracts that contain allergenic and non-allergenic components, and some of these components may crossreact with pollen or other allergens.
Over 13 allergenic components have been identified in peanuts.7 Of these, Ara h 1, 2, 3, 6, 8, and 9 are considered the most important markers of peanut sensitization and are predictive of an allergic response. Ara h 1, 2, and 3 are seed storage proteins, and sensitization to them is associated with a high risk of a systemic allergic reaction: 87% of the children with IgE reactivity have allergic symptoms, including anaphylaxis.8 Ara h 2 is a more important predictor of clinical peanut allergy than Ara h 1 and 3, and is the one most often associated with severe reactions.6 Ara h 6 sensitization is associated with IgE antibodies that crossreact with Ara h 29; rarely does sensitization to Ara h 6 occur in the absence of sensitization to Ara h 2.10
Ara h 8 is a pathogenesis-related (PR)-10 protein, and sensitization to it is associated with a low risk of systemic reaction and a moderate risk of mild, localized symptoms (ie, oral allergy syndrome). In a study of 144 children with IgE antibodies to Ara h 8 (but not Ara h 1-3), 89% were either peanut consumers or did not react to an oral food challenge with peanuts, while 9.7% of the children had mild oral cavity symptoms and 1 child developed mild gastrointestinal symptoms.11 Ara h 8 crossreacts with pollens (eg, Birch and Birch-related tree pollen); Mittag et al showed that 20 patients with Birch pollen allergy and IgE antibodies to Ara h 8 exhibited oral allergy syndrome when exposed to peanut.12
Ara h 9 is a lipid transfer protein, and sensitization to it can result in systemic reactions, including anaphylaxis; 38% (6/16) of subjects sensitized to Ara h 9 were found to have severe symptoms after peanut exposure.9 People sensitized to Ara h 9 are often also sensitized to Ara h 1-3.13 Ara h 9 is not specific to peanut; it crossreacts with fruits with pits (eg, peaches).14
The Peanut Component Panel tests for IgE antibodies to peanut allergens Ara h 1, 2, 3, 8, and 9. Identifying sensitization to peanut component allergens can assist is assessing a patient's risk for a severe systemic reaction.
Individuals Suitable for Testing
Individuals with a history of peanut sensitivity or with documented sensitization by blood or pin prick testing
Method
Fluorescent enzyme immunoassay (FEIA) measurement of IgE antibodies to Ara h 1 (f422), Ara h 2 (f423), Ara h 3 (f424), Ara h 8 (f352), and Ara h 9 (f427)
Analytical sensitivity: <0.1 kU/L
Interpretive Information
Reactivity to Ara h 1, 2, or 3 is associated with a high risk for systemic reaction, including anaphylaxis. Reactivity to Ara h 9 is associated with a variable risk for systemic reaction, including anaphylaxis. Patients who exhibit reactivity to Ara h 1, 2, 3, and/or 9 should be counseled to avoid peanuts, foods that contain peanut products, and foods that have been processed in plants that also process peanuts.
Reactivity to Ara h 8 and nonreactivity to Ara h 1, 2, 3, and 9 indicates a low risk of a systemic allergic reaction. Patients with only Ara h 8 sensitization may consider taking an oral food challenge test, and, if negative, they may not have to avoid peanuts or peanut-containing foods.15
As with all diagnostic testing, results should be interpreted in light of a patient's history, physical examination, and results of other diagnostic testing.
Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 02, 2014, 05:49:34 PM
accidental post sorry
Title: Re: ara h 2 results- borderline
Post by: CMdeux on April 02, 2014, 06:41:08 PM
Stinky is stinky-- long story involving multiple devices and passwords, and never logging out.  LOL.

I'll let her know that she should visit this thread, okay?

Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 02, 2014, 10:00:14 PM
That would be great thanks!
Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 02, 2014, 10:35:55 PM
And what about the following... am I reading this right? My take is that with my son's .48 result to arah 2 he has a 70 to 90% chance of reacting to the ingestion of peanut? Why on the world would his allergist be recommending a food challenge if this is correct???

Info from the ask the expert section of American Academy of Allergy, Asthma and Immunology- found at: http://www.aaaai.org/ask-the-expert/component-testing-peanut.aspx (http://www.aaaai.org/ask-the-expert/component-testing-peanut.aspx)


Significance of component testing to peanut
Question:
10/21/2013
I would like some help interpreting component testing for peanut. I have a 32 yr-old male with a 20 yr history of immediate vomiting and angioedema of the throat when he ate a peanut cookie. Since then he has avoided peanut altogether and he wished to find out if he was still allergic. His skin test was a 4+ with a wheal of 14 mm greater than negative control, histamine was 5 mm wheal. His component tests for Ara h1 and 3 were <0.10 (ref range from Quest Diagnostics) and Ara h2 was 0.31, Ara h9 was 0.90 and Ara h8 was 9.97. Based on these results and the history should he continue to avoid peanut despite being 20 years ago or based on his tests his Ara h8 reveals that he may have developed tolerance.

Answer:
Thank you for your inquiry.

Based upon the results you have supplied, your patient has a high likelihood of reacting to the ingestion of peanuts. An Ara h2 level of about 0.3 has a 70 to 90% predictive value of a reaction upon the ingestion of peanuts (1-3). This would not of course preclude an oral challenge, but the decision to do so would be based upon your own assessment of the risk/benefit ratio and a discussion of risk/benefit with your patient. If you decided to do a challenge, I would suggest doing it outside of the tree pollen season (wintertime) to minimize the chance of an oral allergy syndrome reaction secondary to the Ara h8 sensitization.

Finally, it should always be noted that component testing gives one statistical risks, but not definitive information. Anaphylaxis can occur to any component including those such as Ara h8 which are more classically associated with oral allergy syndrome. In this regard, for your convenience, I have copied below an entry regarding a similar question that was posted to our website 6/26/2013.

Thank you again for your inquiry and we hope this response is helpful to you.

References:

1. Klemans et al: Ara h 2 Is the Best Predictor for Peanut Allergy in Adults, Journal of Allergy and Clinical Immunology: In Practice 11 October 2013.

2. Lieberman J et al:The Utility of Peanut Components in the Diagnosis of IgE-Mediated Peanut Allergy Among Distinct Populations Journal of Allergy and Clinical Immunology: In Practice Vol. 1, Issue 1, Pages 75-82, 2013.

3. Keet et al: Evaluation of Ara h2 IgE thresholds in the diagnosis of peanut allergy in a clinical population. Journal of Allergy and Clinical Immunology: In Practice Vol. 1, Issue 1, Pages 101-103.

Previous posting to Ask the Expert website:
The value of component testing in predicting a systemic reaction to peanut

Question:
6/26/2013
Seven-year-old boy with significant seasonal allergic rhinitis (very allergic to oak, and Birch) and no history of food allergies ate honey roasted peanuts . Within 5 minutes he started with a barky, croupy cough and then developed very significant skin pruritus. He was itching very hard over his chest and neck. Then the cough got worse and he sounded wheezy. He was given a dose of Benadryl, and fortunately he did not have any further complications. The results of my evaluation are: Skin test to Peanut 2+/4+. sIgE to peanut 1.02 kU/L. Ara H 1,2,3,9 <0.1. Ara H 8 24.1 kU/l. According to the review, he should be at low risk for anaphylaxis but the initial reaction is definitely much more than oral allergy syndrome. What would you advise?

Answer:
Thank you for your inquiry.

Your interpretation of the literature is correct in that "classically" the pattern of specific IgE to peanut components seen in your patient would be more likely to predict that only oral symptoms, and not a systemic reaction, would occur upon ingestion of peanuts. However, it is important to understand that this classical interpretation is based only on statistical probabilities. By this I mean that children demonstrating only specific IgE to Ara h 8 are less likely to exhibit a systemic reaction than children exhibiting specific IgE to Ara h 2, for example. Nonetheless, systemic reactions can occur with isolated sensitivity to Ara h 8.

As you can see from the abstract (Asarnoj, et al.) copied below, systemic reactions can occur in children with isolated Ara h 8 sensitivity. This is seen clearly in Figure 3 of this article.

The most reliable test to discern whether a child will exhibit a systemic reaction to peanut is an actual oral challenge. In essence, the reaction exhibited by the child described in your inquiry should be taken at "face value," and the child, at least for the present, should be considered allergic to peanuts. It is clear that patients who have negative skin tests as well as serum specific IgE to foods may still exhibit allergic reactions upon oral food challenge (see Journal of Allergy and Clinical Immunology reference copied below).

Thus, in summary, the results of serum specific IgE testing both in testing to "whole" and component testing, simply serve as guidelines, pointing out the relative risks of a reaction upon ingestion. They are not intended to confer 100 percent predictability as to whether or not a patient will react to the ingestion of the food in question.

Thank you again for your inquiry and we hope this response is helpful to you.

Allergy. 2010 Sep;65(9):1189-95. doi: 10.1111/j.1398-9995.2010.02334.x. Epub 2010 Feb 8.
IgE to peanut allergen components: relation to peanut symptoms and pollen sensitization in 8-year-olds.
Asarnoj A, Movérare R, Ostblom E, Poorafshar M, Lilja G, Hedlin G, van Hage M, Ahlstedt S, Wickman M.
Source
National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Abstract
Background: Allergen-specific IgE testing is often performed with crude peanut extract, but the results may be difficult to interpret because of cross-reactions between peanut and other plant allergens. The aim was to investigate IgE reactivity to peanut allergen components in children from a birch-rich region in relation to pollen sensitization and peanut symptoms.
Methods: From a birth cohort, clinical parameters were obtained through questionnaires and IgE antibody levels to peanut and birch pollen were measured. Different peanut/birch sensitization phenotypes were defined among 200 selected children. IgE reactivity to peanut and pollen allergen components was analysed using microarray technique.
Results: Peanut symptoms were reported in 87% of the children with IgE reactivity to any of the peanut allergens Ara h 1, 2 or 3 but not to Ara h 8 (n = 46) vs 17% of children with IgE reactivity to Ara h 8 but not to Ara h 1, 2 or 3 (n = 23), P < 0.001. Furthermore, symptoms were more severe in children with Ara h 1, 2 or 3 reactivity. Children with IgE reactivity both to Ara h 2 and to Ara h 1 or 3 more often reported peanut symptoms than children with IgE only to Ara h 2 (97%vs 70%, P = 0.016), particularly respiratory symptoms (50%vs 9%, P = 0.002).
Conclusions: IgE analysis to peanut allergen components may be used to distinguish between peanut-sensitized individuals at risk of severe symptoms and those likely to have milder or no symptoms to peanut if sensitized to pollen allergens and their peanut homologue allergens.

J Allergy Clin Immunol. Author manuscript; available in PMC 2012 November 1.
Published in final edited form as:
J Allergy Clin Immunol. 2011 November; 128(5): 1120–1122.
Published online 2011 August 11. doi: 10.1016/j.jaci.2011.07.012
PMCID: PMC3205298
NIHMSID: NIHMS319256
Outcomes of office-based, open food challenges in the management of food allergy
Jay A Lieberman, MD, Amanda L Cox, MD, Michelle Vitale, RN, and Hugh A Sampson, MD

Sincerely,
Phil Lieberman, M.D.

Title: Re: ara h 2 results- borderline
Post by: Stinky10 on April 02, 2014, 10:44:49 PM
I didn't read the whole thread.....I'll come back to it....but thanks to a pm from cm I can offer some quick help. 

I've heard
http://www.allassoc.com/dr-kevin-dooms/ (http://www.allassoc.com/dr-kevin-dooms/) 

is good

We go to http://www.nwasthma.com/providers/doctors/thao-ngoc-tran-md (http://www.nwasthma.com/providers/doctors/thao-ngoc-tran-md)  and like her very much.  She's up on the research and conservative which worked for my family

There really are a lot of options.   Where is WA are you looking?  www.wafeast.org (http://www.wafeast.org) has a listserv and a closed fb page both would be a great resource for you.
Title: Re: ara h 2 results- borderline
Post by: CMdeux on April 02, 2014, 10:51:22 PM
Thanks Stinky!   :heart:


Quote
And what about the following... am I reading this right? My take is that with my son's .48 result to arah 2 he has a 70 to 90% chance of reacting to the ingestion of peanut? Why on the world would his allergist be recommending a food challenge if this is correct???

This is why I think it might well be helpful to see a real specialist in FOOD allergy, who is up to date on current research and stuff.  It's going to come down to very specific history details and a lot of other factors, probably... including your own risk tolerance (and the doc's).

KNOWING what kind of threshold you're dealing with might be worth it if your risk is 50-50 and your doctor is very conservative with respect to symptoms (that is, would stop the challenge before the development of really obvious objective symptoms).

Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 06, 2014, 03:20:01 PM
I got my sons result paperwork in the mail. His .48 to ara h 2 is actually considered to be a low positive result by the lab. The doctor must have read the results wrong.  :( :pout:

I guess I am looking for a new allergist now... wish there was a "top" food allergy specialist in my area... it doesn't look like there is an allergy department at Seattle Children's hospital which is disappointing. Supposedly they are looking for funding and want to do desensitization therapy  in the future but not now. I found a place in town that seems to do food allergy research but doesn't actually treat patients.
Title: Re: ara h 2 results- borderline
Post by: CMdeux on April 06, 2014, 03:58:32 PM
Contact WA-FEAST-- they'll know who is in your area.   :yes:
Title: Re: ara h 2 results- borderline
Post by: twinturbo on April 06, 2014, 04:11:14 PM
Yes, FAI had a branch office in the Sea-Tac area. There will be some good allergists there.
Title: Re: ara h 2 results- borderline
Post by: evergreenmom on April 06, 2014, 04:25:46 PM
What is FAI?
Title: Re: ara h 2 results- borderline
Post by: Stinky10 on April 06, 2014, 06:44:42 PM
Food Allergy Initiative

You might want to check out

http://www.seafac.org/seattle-food-allergy-consortium/consortium-members/ (http://www.seafac.org/seattle-food-allergy-consortium/consortium-members/)

Wa-feast isn't going to recommend a dr to you - but you can talk to members on the the yahoo list or fb - I think I posted links above.