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 Post subject:
PostPosted: Wed Jul 12, 2006 3:34 pm 
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Joined: Sat Apr 16, 2005 12:09 am
Posts: 1054
k-rae wrote:
I haven't heard of that correlation....is that coming from you allergist?

Yes from our allergist -- was just curious if others were also given this info.


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 Post subject:
PostPosted: Wed Jul 12, 2006 3:41 pm 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
There is a thread, "Can Deadly Peanut Allergies Be Cured?" under "Allergies in the news" about a study being conducted at Duke Medical Center. They are desensitizing children with peanut allergies by feeding them a tiny amount every day and increasing ever so gradually.

That study sounds very promising. I don't see why it wouldn't be possible for other allergens as well.

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Sat Jul 15, 2006 10:27 am 
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Posts: 1054
I found some interesting information on how the RAST test is used and results are interpreted. It is specifically in reference to testing for peanut allergy -- I bolded some very interesting points. The following quote was taken from: http://www.medic8.com/healthguide/artic ... lergy.html

Quote:
Peanut allergy can be tested in 3 ways.

1-Allergy skin test - this is a simple and fast way to test for peanut allergy. It involves placing a drop of a weak solution of peanut (plus you need positive and negative control solutions to interpret the tests properly). The drops are pricked and the results are measured 15 minutes later. A positive result looks like a little mosquito bite. If there is a good history of a peanut allergic reaction the skin test is a simple way to confirm the allergy. If there is no history of a reaction to peanut a positive test needs careful interpretation. The size of the skin test reaction does not indicate what reaction you may have.

2
-Peanut RAST test - the RAST test is done on blood, and measures the amount of IgE against peanut. As with the allergy skin test, if there is a good history of a peanut allergic reaction the RAST test is a simple way to confirm the allergy. The RAST result is usually reported in two ways - either as 1+ to 4+ or as an exact number.

The exact number gives a more precise indication of how likely it is a reaction will occur on exposure to peanut. For example a result of 15kUA/l means it is 95% likely there will be a reaction. It does not tell you what the reaction will be. Three people with levels of 15kUA/l could have very different reactions such as eczema in one, hives in another, and anaphylaxis in the third.

The RAST can also be used to assess the chance that peanut allergy has resolved (see below).

3-Peanut challenge - very occasionally there is a good history suggesting peanut allergy but negative results on skin and RAST tests. In this situation a peanut challenge may be considered. This should only be undertaken with careful hospital supervision in case a reaction occurs. The challenge will usually start with a tiny amount of peanut (eg. 1/8th of a gram) to try and avoid causing a significant reaction.
___________________________________________________________

Peanut challenge may also be suggested for older children who have possibly outgrown their peanut allergy (see below).

The problem is that all the studies show that most of the children who do grow out of peanut allergy will continue to have positive skin tests and RAST tests to peanut. This means the tests alone cannot determine which children have grown out of the allergy.

However if the RAST result is very high (eg. above 15kUA/l) it is extremely unlikely the allergy has gone away.

Given the difficulty of managing peanut allergy, repeat evaluation is warranted. It is probably best to delay this until age 4 years in order to give the best chance that a child has outgrown the allergy. At that time it's worth repeating the allergy tests if there have been no recent reactions on accidental exposure.

If the skin test/RAST test is negative then a cautious peanut challenge should be considered.

If the skin test is positive and the RAST test is low positive then a cautious peanut challenge should be considered.

If the RAST test is highly positive then it's very likely the allergy is persistent, and most likely that it will be life long. Ongoing avoidance and an up to date action plan are needed.


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 Post subject:
PostPosted: Sat Jul 15, 2006 11:54 am 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
Thanks ethansmom, that was a very informative quote. I will be able to understand how the results are interpreted on Wednesday.

I'm so hoping that the RAST will be negative too, but that means that the Dr. will do a food challenge and that's a little unnerving, but we need to know and get to the bottom of this. I have mixed emotions about it. I have a feeling that, like with a lot of things in life, the results won't be so black and white.

If she does have a food challenge and passes it, then I'll be left wondering what happened to her on that February day? Could it happen again? Should we hang on to the Epi-pen a while longer?

Oh well, wait and see. I'll keep you posted.

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Mon Jul 17, 2006 9:25 pm 
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Joined: Tue Nov 29, 2005 4:04 pm
Posts: 2044
Location: Gatineau, Quebec
Thanks ethansmom. That's very helpful.

Quote:
The exact number gives a more precise indication of how likely it is a reaction will occur on exposure to peanut.


That had been my understanding, but I didn't have any handy references to back me up, (and I was too tired to seek any out!) so I didn't want to post. As you said, the existing tests do not indicate how severe a reaction will be, which of course is the million dollar question.

Nicole - from what I've seen of what's happened with the kids of some of the members of my support group, "outgrowing" a peanut allergy is not as easy as one might think. It's truly not black and white. There is the food challenge itself, of course, and then there is the ongoing challenge of making sure that the person gets enough peanut into their system on a regular basis to ensure that the allergy "doesn't come back". For some kids that's not a problem, but for kids who really don't like peanut or peanut butter, it's been difficult.

I know that for the members of my support group whose kids have outgrown peanut, they have been advised to carry an epi auto-injector for at least a year following the challenge, just in case. I'm sure your allergist will give you good advice on that front.

My oldest son is actually a candidate for a peanut challenge, according to our allergist, but my son has said that he doesn't want to do it right now, and we are respecting that. We're in a double bind in that my youngest is quite allergic to peanuts, so we wouldn't let any kind of peanut product in the house -- so if my oldest has actually outgrown the allergy, how would we ensure that he got his "daily/weekly" dose of peanuts?? It's just too complicated to contemplate at the moment, to be honest. So we've decided to just avoid the problem for now. (Life is complicated enough!!)

Anyway, good luck on Wednesday!! I hope you get some straight answers. :)

K.

_________________
Karen, proud Mom of
- DS1 (12 yrs): allergic to cashews, pistachios, Brazil nuts, potatoes, some legumes, some fish, pumpkin seeds; OAS
- DS2 (1o yrs): ana. to dairy, eggs, peanuts; asthma


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 Post subject:
PostPosted: Tue Jul 18, 2006 8:47 am 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
Thanks so much Karen!

As usual, your comments are at once sensible, objective and encouraging!

I will post the results for sure.

As for having one child with a peanut allergy and another without, my younger daughter's allergist (who was on maternity leave when my oldest had her reaction, that's how we ended up with a different allergist) recommended feeding her peanuts once a week, since she had a 3+ wheal for peanuts. She said she could develop an allergy to peanuts because she shows a sensitivity, therefore it would be useful to feed her peanuts or pb once a week. So we bought these little individual pb and crackers snacks (which I keep in a plastic bag in the cupboard, so no risk of cross-contamination with anything else) and when my oldest is out, she has one, after which she promptly washes up.

The allergist said: "Either you give her pb to avoid her becoming allergic or you treat her like she has an allergy and don't feed her anything with peanuts". I thought to myself that it's much better to live without an allergy... :?

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Tue Jul 18, 2006 1:05 pm 
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Joined: Tue Nov 29, 2005 4:04 pm
Posts: 2044
Location: Gatineau, Quebec
That's funny about the little pb cracker thing. Another friend is doing the same thing - feeding one of her kids a Reese's peanut-butter cup once a week to try to ensure he doesn't develop an allergy to peanuts!

I guess, given the study being done at Duke Medical Centre ( http://www.allergicliving.ca/forum/viewtopic.php?t=1147 ), that it isn't perhaps a bad thing to do.

I wonder what we'll think of all this, say, 10 years from now?

K.

_________________
Karen, proud Mom of
- DS1 (12 yrs): allergic to cashews, pistachios, Brazil nuts, potatoes, some legumes, some fish, pumpkin seeds; OAS
- DS2 (1o yrs): ana. to dairy, eggs, peanuts; asthma


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 Post subject:
PostPosted: Tue Jul 18, 2006 1:50 pm 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
Yes Karen, in 10 years from now, all these food allergies will be a thing of the past. At least that's my hope... :D

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Wed Jul 19, 2006 4:58 pm 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
Well, we had our appointment with Dr. Waserman today and guess what? The RAST came back negative for PEANUTS and ALL NUTS!

They then repeated the skin test and added other foods, and everything was negative! Based on that, the Dr. is sending my daughter for a food challenge next month (more waiting!), as she doesn't do them in her office. She wants to wait that long because she is also dealing with my daughter's asthma and her spyrometry test was poor again. She is boosting her Advair dose for a month and will repeat the spyrometry test then and send us for the food challenge. (I don't know if that means waiting still longer for the food challenge appointment).

I am very encouraged however and allowing myself to hope for the best now. The only nagging question remains "What was it that caused that reaction back in February?". I guess the food challenge will be the last hurdle.

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Wed Jul 19, 2006 9:47 pm 
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Joined: Sat Apr 16, 2005 12:09 am
Posts: 1054
That's great Nicole! I'm really happy for you and your daughter ... I know you still have questions unanswered, but it's really good to hear that she doesn't *seem* to be allergic to nuts/peanuts.


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 Post subject:
PostPosted: Fri Jul 21, 2006 9:13 am 
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Joined: Sun Mar 05, 2006 1:05 pm
Posts: 528
Location: Burlington, Ontario
Thank you ethansmom, I hope and pray for good news like this for everyone else on the board.

I am relaxing a bit, but not completely, that is until she passes the food challenge...you never know!

Just wish we didn't have to wait so long. Oh well!

_________________
15 year old - asthmatic, allergic to cats, dogs, horses, waiting to be "officially" diagnosed for anaphylaxis
12 year old - asthmatic, allergic to tree pollen and mold, OAS
Husband - Allergic to amoxycillin
Self - Allergic to housework only


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 Post subject:
PostPosted: Fri Jul 21, 2006 1:39 pm 
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Joined: Fri Jan 06, 2006 8:22 pm
Posts: 154
Location: Georgia
ethansmom wrote:
I think I'm really confused now....so, the RAST isn't a predictor of the severity of an allergic reaction, but does it accurately reflect the presence of an allergy? What do you mean -- false positives and false negatives with the RAST?


The RAST(bloodwork) is a measure of IgE in serum. It indicates the presence of antibodies to an allergen, but not necessarily the severity of the reaction.

For example, I am a class 3 (moderate) for shellfish. Stayed at that level for years. But, I believe, due to repeated exposures I am now inhalant and contact reactive to shellfish. Can't get near it. No shared product lines, or produced in the same facility.

Alternately, I am also a class 3 for egg white. I have not had a reaction I can trace to egg. But due to the increase in severity of my shellfish allergy, I am taking no chances with this one. Avoiding all eggs, egg products, etc...

Someone with a class 2 RAST *may* exhibit full-blown anaphylaxis and someone with a class 4 RAST *may* have a "hives-only" reaction.

RAST is a good tracking device for allergen levels. And a good confirmation device for suspected allergy reactions.

I have also, at times, come up RAST negative for my known allergens. There are many reasons for this.

Assume the lab has run the proper controls/standards and the test in working range:

1. The term "false-positive" is really incorrect. Meaning that you *do* have the IgE to an allergen in your system, and it *was* detected. Your body may just choose not to react. Not that the RAST test detected something that wasn't there.

2. A "false-negative" can follow the same path. Just not detected in *that* sample. Not that there was anything wrong with the test. Just that there may be interfering substances, or some other problem with your serum. Usually, following a reaction the RAST will rise. And sometimes, following a very severe reaction, you may actually test RAST-negative (the IgE has been depleted). :?

Nicole,
Great news about your daughter. Hope the challenge goes well.

Hope this helps,
Daisy


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 Post subject:
PostPosted: Wed Jul 26, 2006 10:07 pm 
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Posts: 1054
Yes Daisy -- thanks for the detailed explanation. I *think* I've got it figured out (more or less :lol: ). Was just at the allergist today and confirmed that my son's RAST for peanut was 90 KU/L (Level 5), and his doctor pretty much said that it is extremely unlikely that he'll outgrow it :( . He does feel that we'll see a cure / treatment for PA by the time he's a teenager - so let's hope!


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PostPosted: Thu Aug 31, 2006 6:01 pm 
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Joined: Sat Dec 31, 2005 9:00 pm
Posts: 70
Location: Victoria, BC
I couldn't believe it when I heard his number was 46KU/L! I panicked and was kicking myself because we thought we did all we could to avoid any and all traces of peanuts! He did this test a year ago and the result was 21KU/L. The first time he did the test, it was 7KU/L. I immediately called my son's allergist/asthma doctor to set up an appt. to go in and discuss the results with him. But, in the meantime, I knew to come to this support group at Allergic Living. I wanted and needed to read what everyone else was going through and how they were getting through it. So far from all the reading I've had on this topic, it's proved very helpful. I will know more tomorrow but thanks for all your posts so that I can get a better picture as to what the RAST results mean and it doesn't necessarily mean that my son is a walking time bomb ready to explode at the sign of one peanut.

I will keep you updated!

Thanks again.

_________________
Son-anaphylaxis to peanuts, allergic to soy, peas, beans, tree nuts, cats, trees, grass & mold. Asthmatic due to colds & allergies.

Daughter-anaphylactic to kiwi fruit, allergic to soy, dairy, trees, grass, cats & dust


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 Post subject: Update...
PostPosted: Thu Sep 14, 2006 1:53 am 
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Joined: Sat Dec 31, 2005 9:00 pm
Posts: 70
Location: Victoria, BC
We redid the peanut test and also tested him for soy and peas (there is no blood test for beans), and also for almonds, hazelnuts, brazil nuts and coconut.

The peanut test came back basically the same but the soy and peas test results came back indicating that he is now allergic to soy, peas (part of the legume family) and that is why his peanut RAST scores were high because of the soy and peas we were feeding him. Three years ago when he was tested for soy and peas at the same time as the peanut test, their results were negative. So, total avoidance of all legumes has been advised. He is also now allergic to almonds and hazelnuts which are a part of the tree nuts family, right? So, now total avoidance of all nuts has been advised.

We are seeing a nutritionist and another allergist to confirm and get more answers. These last three weeks have been a nightmare.

Will keep you updated. Any advice?

Nancy

_________________
Son-anaphylaxis to peanuts, allergic to soy, peas, beans, tree nuts, cats, trees, grass & mold. Asthmatic due to colds & allergies.

Daughter-anaphylactic to kiwi fruit, allergic to soy, dairy, trees, grass, cats & dust


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