OAS question

[spacecanada]

So, after suspected potato reaction number two, I have been researching like mad and wonder if all my reactions boil down to some sort of extremely severe anaphylactic OAS.

Just looking at:
http://www.inspection.gc.ca/food/information-for-consumers/fact-sheets/food-allergies/oral-allergy-syndrome/eng/1332351950134/1332352076501

The only thing I showed extremely positive to on my SPT was birch, and that wheal was ~40mm, which I think quack allergist said was class V (or maybe IV++). (I have no idea if that is relatively big or small.) I don't normally have seasonal allergies at all, though this spring I have been a bit snotty which is unusual. Birch isn't on our pollen counts because it isn't common here, though aspen and poplar are high right now. Hazelnut tree pollen is low. (I didn't know hazelnut trees were common here?) Aspen and birch are pretty close in botanical structure, cousins if you will.

Definite reaction anaphylaxis history to hazelnut, walnut, almond, peanut, and potato and possibly mild reaction to tomato (both cooked) -- all cross-reactive with birch. I have had severe reactions in the middle of winter, however.

What do you guys think? Can someone have extremely low threshold anaphylaxis reactions due to OAS alone?  Just trying to figure this puzzle out so I have something to go with until my allergist appointment, whenever that will be.

[CMdeux]

Wellllllll--

understand that among persons with anaphylactic CLASSIC food allergy, the "rules" with OAS seem to be quite a bit different than for everyone else who has "allergies."

That is, someone like my neighbor who has pollen allergies might have birch or grass pollen OAS, and be able to eat those things safely, but for annoyance, or but for during that few weeks of the year when that pollen cup is full.

There might be little-to-no danger in eating them.

Someone who has demonstrated ability to anaphylax, particularly from ingested allergens, on the other hand-- what I've gotten out of the literature, textbook references, and anecdote over the years is that people with anaphylactic food allergies tend to have the ability to have OAS become anaphylactic as well.

There's no bright line dividing "OAS" from "food allergy" if you already have IgE-mediated food allergy, in other words.  Oh, sure, it might start out that way, and maybe even be stable for some people-- but not for everyone.

It doesn't seem THAT rare to me among people on the end of the food allergy distribution to have an OAS trigger go wild and suddely jump ship to become a food allergen that is capable of causing systemic reactions.  Some of them can still get away with heat-denatured allergen, and some cannot. 

DD has apparently had this happen to her now with apples.    DH has had it with melons and apples both.  I have it with oranges (well, really ALL citrus fruit).

What is potato even cross-reactive with, though?  Isn't it grass? 

[PurpleCat]

I'm not one of the scientific minds here so I'll share what I know based on our experience.  Everybody is different.

According to our allergist OAS and Anaphylaxis, while both a kind of allergic reaction, are not the same thing.  OAS is not life threatening and it's symptoms are related to the mouth.  Accidental exposure is not pleasant but is considered OK.  Having said that, a food that has caused OAS in the past can become a food that causes anaphylaxis.

My DD has OAS to fruits related to birch trees (she is highly allergic to all tree pollens).  Basically anything with a pit and pears.  She tests positive to apples, but she eats those often.  She can eat the canned/jarred version of all of these fruits.

My DD has anaphylaxis to all melons which are related to ragweed (which she is mildly allergic to).  She can not have any form of these fruits.

My DD has anaphylaxis to pineapple which is related to latex (which DD is not allergic to) and she does not like raw banana but loves banana bread (makes me think she is OAS to banana) and yet she eats kiwi almost every day.

Weird huh? 

Allergies are so not easy to decipher!

Hope you can see your allergist soon!

[Janelle205]

My allergist seems to think that this was probably how my food allergies started.  I'm allergic to nearly all of the environmental allergens, and massively allergic to birch.

20 years ago, if I ate an apple, my mouth, throat, and ears would itch and tingle.  Eventually it just kept getting worse.  Now I react to fully cooked and processed apples, and have had anaphylaxis from contact ingestion.  Season does not matter for these and most of my other fruit allergies.

I have to avoid most of the cross reactive foods, though I don't have a problem with potatoes - I eat them and peel them with no issues.  Most non-tropical fruit is out for me, except for berries.  I can eat bananas only in the winter. 

[Mookie86]

My OAS isn't mouth only.  An apple eaten during ragweed season caused my nose to gush like a faucet on full blast.  My throat was really irritated, and I couldn't stop coughing long enough to say anything.  Ears got really tingly as well.  I took Benadryl and was OK soon. 

[ninjaroll]

Qualified yes.  The specific food(s) must be related to a particular culprit pollen for that perfect storm.

[spacecanada]

So I guess I am pulling at straws trying to find an answer.  Your answers all seem like what I though initially, before I got so desperate for answers. This seemed almost too easy to blame, though I realized most OAS is merely irritating, not life-threatening. They do say it is possible, but what is mentioned here reinforces that it would be very unlikely. 

My nut allergies started in high school, maybe before, with itchy mouth, itchy ears, and sometimes irritated throat we just wrote off as my 'normal' or asthma attacks. Could that have been OAS back then, who knows. No history of hay fever, ever though...

About a year ago I started getting stomach aches and diarrhea after eating.  No mouth/throat/systemic symptoms then. My GP and I figured was due to a new food intolerance we narrowed down to potatoes and tomatoes.  I wonder if that was the start of this new allergy too.  I asked if it could be a new allergy and my GP said it was unlikely but we had many doses of Epi just in case it turned out that way.

Potato and tomato are linked to birch allergy, as well as a long list of other foods including all my current allergens. Birch was the only positive on my SPT, and spectacularly so, despite no hay fever.  Everything else I am allergic to tests negative in blood work and SPT. You can see how easy I could connect those dots with OAS, even as a primer way back when before the food allergies turned so severe.

For now, I guess we shall avoid potato until we see the allergist. We are going to test cooked then raw tomatoes at home later this month to see if they are problematic as well. I guess if the allergist doesn't think of the connection I can always ask about it then. I should get a call with my allergist appointment time on Tuesday.

Thanks everyone for chiming in. 

[Janelle205]

I would expect that if it were an OAS issue, you would also have issues with some of the fruits that are more strongly correlated with birch pollen issues, like apples and stone fruit.

And I would agree with the assessment that it's pretty rare.  I got my first epi when the doc thought that it was 'just OAS' but he admitted that he wouldn't normally prescribe it for that, but more wanted me to carry because of severe asthma issues and living in the middle of nowhere.  They are definitely 'real' allergies now, but the doc has stressed to me that is awfully rare, and doesn't think that my family members with OAS need to worry about it becoming severe.

[maeve]

DD has OAS to cucumber and cantaloupe. Her allergist at Hopkins (well regarded) has said it can develop into a true food allergy. We still have had her try either again; though we have been told we can try. Neither is essential to her diet. She is able to eat honeydew (though admittedly doesn't like it) and watermelon.

[catelyn]

My reaction to tomato wasn't tomato at all.  It was what I was always eating with tomato.  It wasn't allergic either but it usually LOOKED exactly like that.

[Mookie86]

How do you know when it has crossed from OAS to true allergy? I wonder if that's happened with me to apples.

[PurpleCat]

I'm guessing that is different for all.  For DD, hers have changed when the symptoms go past her throat and suddenly include "chest squeezing".

[CMdeux]

The difference is local versus non-contacted locations/systems.

So mouth swelling-- even hives on the face-- could still just be super-bad OAS.

On the other hand, hives on your arm, or watering eyes-- probably not.  Asthma?  DEFINITELY not.

[Mookie86]

I got tingly throat, uncomfortable feeling in ears, nose dripping like a gushing faucet, coughing so much I couldn't talk. I can't remember exactly if lips swelled some. I know they did for something,  but I can't remember if it was due to apple.  It resolved with Benadryl and Allegra.

Does that sound like OAS or true allergy? Either way, I avoid it. Not avoiding cross-contamination, just actual apples.

I should add I am fine with granny smith apples.

[PurpleCat]

Mookie, our allergist tells DD not to eat the part of the apple near the stem.  She said that is where the pollen/protein is concentrated in the fruit, where it hangs from the tree.  So when DD eats an apple, she avoid the top part.