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Author Topic: New Poster With False-Positive Questions  (Read 3125 times)

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Offline SandyWood

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New Poster With False-Positive Questions
« on: May 25, 2014, 03:48:08 PM »
I just had my second food allergy test done a few weeks ago while getting retested for my nasal airborne allergens. I was originally tested back in 2007 and had pretty much the same results.  The nurse pricked my finger and then collected the blood on a card for the lab to test. They did a 96 Food IgG Panel of testing for me.

The results came back in the High range for Casein, Cheddar Cheese, Cottage Cheese, Cow's Milk, Mozzarella Cheese, Whey, Yogurt and Egg Whites.  Also saw High results in Kidney, Pinto and Soy Beans.

 I've eaten alot of these foods in my life and never had a bad reaction to them. Could they possibility be false positives? Or do I just not react to them the same that other people do? Or am I a time-bomb waiting for the right time to really react? This morning I had bacon and eggs for breakfast, forgetting about my Egg White sensitivity. I've felt good all day. I'm curious if I should get retested again.

Thanks for any advice anyone has!

Online hezzier

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Re: New Poster With False-Positive Questions
« Reply #1 on: May 25, 2014, 04:42:34 PM »
If you are having any reactions to foods, then you need to see a board certified allergist to have a skin prick test or a rast blood test.  If you are not having any reactions, then I would ignore the test results.  An IgG blood test is not the correct test to evaluate potential allergies.


Here's an explanation of the difference between IgG and IgE. 

IgG antibodies are found in all body fluids. They are the smallest but most common antibody (75% to 80%) of all the antibodies in the body. IgG antibodies are very important in fighting bacterial and viral infections. IgG antibodies are the only type of antibody that can cross the placenta in a pregnant woman to help protect her baby (fetus).

IgE antibodies are found in the lungs, skin, and mucous membranes. They cause the body to react against foreign substances such as pollen, fungus spores, and animal dander. They are involved in allergic reactions to foods, some medicines, and some poisons. IgE antibody levels are often high in people with allergies.

Offline Janelle205

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Re: New Poster With False-Positive Questions
« Reply #2 on: May 25, 2014, 06:21:21 PM »
Agreeing with what Hezz had to say about IgG vs. IgE - IgG is not what you want to be looking at for diagnosing a food allergy.  In addition, if you have been eating those things for your entire life without reacting to them, you're almost certainly not allergic to them.

What symptoms do you have that made you get tested/suspect a food allergy?

Offline SandyWood

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Re: New Poster With False-Positive Questions
« Reply #3 on: May 25, 2014, 08:40:37 PM »
Thank you both so much for the very helpful and eye-opening explanations. I've been seeing a ENT who was doing my airborne allergy therapy for about 8 years now. Twice he has tested me for food allergies along with the airborne allergies and both times the tests he ran were the 96 Food LgG Panel. Up until today. I haven't ever had any food allergy symptoms but I've gone with the program and let him test me for food allergies. Now I'm wondering if he's just making $$$ off me for these tests. I never said I had any food allergies but I thought it would be good to know anyway in case something was amiss. I thought maybe I was missing some subtle allergy symptoms so I've cut out the dairy in my diet now for a few weeks to see if it makes any difference. It doesn't sound like it's going to make any difference.

At this point, would it be advisable to go and insist on an lgE test or in the absence of any systems, just leave it be and enjoy my dairy?

Offline Janelle205

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Re: New Poster With False-Positive Questions
« Reply #4 on: May 25, 2014, 11:10:37 PM »
Without symptoms, I would honestly let it be and enjoy dairy - because cheese is delicious.

I wouldn't ask for an IgE test - without any symptoms, it is probably asking for trouble.  Even the skin testing and IgE blood testing pretty commonly produces false results.  I test positive for things that I can eat without problems and I know other people on the board do as well. 

Offline YouKnowWho

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Re: New Poster With False-Positive Questions
« Reply #5 on: May 26, 2014, 09:34:09 AM »
On one hand the dairy is likely not a true food allergy.  However, dairy products do have a tendency to increase mucus production which can lead to stuffy noses, constant throat clearing, etc.

DH is not allergic to dairy but there are certain times of year he avoids as much as possible (not to the point of label reading, just outright visible dairy) otherwise it exacerbates his issues.  For example, he is horribly allergic to ragweed which is prominent in August and September here, he is miserable.  He avoids dairy at this point because the overabundance of mucus will lead to him getting sick with sinus infections or he will never get on top of it with his daily antihistamine routine which is already way more allergy medication than the average person takes.
DS1 - Wheat, rye, barley and egg
DS2 - peanuts
DD -  tree nuts, soy and sunflower
Me - bananas, eggplant, many drugs
Southeast USA

Offline SandyWood

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Re: New Poster With False-Positive Questions
« Reply #6 on: May 26, 2014, 10:33:21 AM »
Thanks to you all for the explanations and feedback. I have a follow-up with a new ENT in July who I will run my concerns by. You guys have been very supportive!

Offline lakeswimr

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Re: New Poster With False-Positive Questions
« Reply #7 on: May 27, 2014, 06:54:58 AM »
I don't think the ENT is trying to make money with the tests so much as uneducated about food allergies.  Food allergists do not use the type of test the ENT used and do not consider it valid or reliable.  Current food allergy guidelines call for NOT testing unless a person is exhibiting signs of a food allergy to a particular food due to the high false positive rate of even the testing that allergists uses (IgE testing by skin or vials of blood).  Your ENT used a form of testing that is not valid or reliable and tested for things even though you don't have symptoms of a food allergy.  I would not even bother to discuss food allergies with this person any further.  They may be a great ENT but in general for anything in the allergy realm, allergists are going to be better, even for seasonal allergies.  A finger blood test is NOT valid or reliable for testing for seasonal allergies, either! 

I'd recommend switching to a good allergist for your seasonal allergies if the ENT isn't able to treat you sufficiently and I'd just go on eating dairy.