Chart for inturpreting skin test results?

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I cannot find one anywhere...any help?

By cathlina on Feb 24, 2009

Specific IGE Class KU/L Level of Allergen Specific IGE Antibody

0 <.035 Absent/Undetectable 1 0.35-0.70 Low Level 2 0.71-3.50 Moderate Level 3 3.51-17.5 High Level 4 17.6-50 Very High Level 5 51-100 Very High Level 6 >100 Very High Level

By lakeswimr2 on Feb 25, 2009

Cathlina, that is for blood tests, not skin tests.

My understanding is for skin tests 3 or lower is considered negative (although false neg are certainly possible.) Anything 8mm or higher is strongly correlated with serious reactions and NOT outgrowing the allergy.

They usually give 2 numbers. The first is the size of the wheel (raised area) and the 2nd is the size of the redness. The #s I gave above are for the raised area.

Skin testing alone without any symptoms is not a reliable way to diagnose a food allergy. It is only 50% accurate for positives and over 90% for negatives. My son's allergist considers it *more* reliable than blood testing. In any case, if you have not had a reaction to a given food it isn't a good way to diagnose an allergy given the high false positive rate. In someone who has a history of reaction to a given food or is trying to figure out which food caused a reaction it can be very helpful.

Good luck!

By cathlina on Feb 26, 2009

Sorry...couldn't find skin test diagnostics on the net so posted the RAST. Many people with PA will not take a skin test including me.

By barbfeick on May 1, 2009

There are alternatives to the skin test.

By lakeswimr on Apr 28, 2009

I'm sorry Barb but that type of testing is not accurate for people who have life threatening food allergies. If someone thinks they are dealing with food allergies they ought to see a board certified allergist and have real testing done (CAP RAST or skin testing.) Sending people to alternative practitioners is dangerous. Someone could end up dying from not getting a proper diagnosis or proper mediation (epi pens, emergency plan, etc.)

You shouldn't not be recommending this type of testing here in my opinion. There is NO such thing as a for sure "minor" IgE mediated food allergy. Having a food allergy (IgE mediated food allergy) means one has a potentially life threatening condition. Many people who die from food allergy reactions (seems the majority) did not know their condition could be fatal and did not treat with epi pens or didn't treat with them in time. Many did not carry epi pens and did not realize their past reactions were the signs of a serious reaction. The majority of people HERE at pa.com have potentially life threatening food allergies or children with potentially life threatening food allergies. This is NOT the right place for alternative testing/treatments. Sorry.

By Bunny on Apr 29, 2009

Barb,

I have read your blog about vaccinations causing food allergies and I have to say that I agree with you on that one. That has been my working theory ever since my son developed his life threatening food allergies.

Having said that, I gotta agree with Lakeswimr on this one. I hear your point that there are more than just Ige mediated food allergies, but most of the people on this board are dealing with life threatening, Ige mediated allergies. The original poster asked about interpretation of skin tests. Those are meant to measure the Ige allergies.

I am a big proponent of alternative testing and treatments in just about every category EXCEPT with respect life threatening food allergies. The testing you are talking about may have some utility for food intolerances, but I highly doubt that it is going to helpful at all with respect to true, life threatening, allergies.

I think it is important not to confuse anyone who might be new to all of this.

By barbfeick on Apr 29, 2009

IgE represent only a portion of the food allergies. I am not saying you should only rely on alternative screening. It is pretty clear that you should not rely only on mainstream medical tests, either.

The Complete Idiot's Guide to Food Allergies by Lee H. Freude, M.D., and Jeanne Rejaunier, Penguin Group, 2003 pg 72 - "Most frequently the immunoglobulin involved is IgE. This reaction occurs in a very short period of time after eating the offending food, and is called an immediate reaction. Other reactions can involve IgG, IgM, IgA, and S-IgA. These can occur at a later time and are called delayed reactions."

If you know of a good medical test that can pick up IgG, IgM, IgA, and S-IgA - please enlighten me.

And there is also a cell-mediated immune response. Again, show me a good medical test for this.

So I would say, yes, absolutely go to your allergist and get the regular medical allergy tests. Then find someone who does computerized electro dermal screening.

And it is sad that the patient died at the alternative practitioners office when they were trying to be desensitized. But there are a number of patients who have died under the care of regular allergists, too. One of the nice things about EDS is it does not involve the use of anything that should cause an allergic reaction.

By lakeswimr2 on Apr 29, 2009

Barb,

Again, most people here have IgE mediated food allergies and there is NO reason to seek alternative care in the case of IgE mediated food allergies since there aren't any alternative treatments that cure food allergies. There are not any alternative tests that have accuracy to test for IgE mediated food allergies. Unfortunately there are not any alternative tests that work for non-IgE food reactions, either. The gold standard for non-IgE reactions is to JOURNAL every symptom and every food one eats and figure out food reactions that way.

By barbfeick on May 1, 2009

There is at least one post on this site about a negative IgE test but the kid still had a severe peanut allergy. Most people may only have IgE allergies but this site is not limited to only people with IgE allergies.

You seem very anti - alternative medicine.

By lakeswimr on Apr 29, 2009

This site is for people with peanut allergies. That means IgE to most people. When you are talking about non-IgE food reactions peanut isn't very common. I would guess nearly everyone here save a few are dealing with IgE. Given that and that alternative food 'allergy' testing isn't accurate I don't think the info is helpful.

Skin and CAP RAST blood tests are both about 50% accurate for positive results and over 90% accurate for negative. They are not a good way to diagnose a food allergy by themselves and good allergists use them in combo with reaction history to make a diagnosis. We also now have positive and negative predictive values for many of the major allergens with these tests and these can help tell when a person might have outgrown and allergy or if a person is likely to have anaphylaxis upon next exposure. Testing his helpful. It is certainly possible to have a neg test and have an IgE mediated food allergy.

Conventional allergists do NOT "denounce blood tests and favor skin tests." That's not true AT ALL! It is actually split about 50/50. Most allergists do favor one or the other type of test but about half favor skin testing and the other half prefer CAP RAST blood testing. My son's allergist feels skin testing is more accurate. We have both done upon my request.

I'm certainly NOT against alternative medicine. I got preg with my son working with my naturopath. I have seen alter med docs for at least 16 years or more. I know that alternative medicine is NOT for use for IgE mediated food allergies, though.

The presence of IgG indicates *tolerance*, not a food allergy or food sensitivity. Allergists do not use blood tests that test for IgG. Bastyr, as alterna med as you can get, the famous and great naturopathic university says IgG testing is not reliable or indicative of a food allergy or sensitivity.

Really, you are spamming this site, right? don't people normally pay to advertise? Someone could die as a result of what you recommend so I'm posting. Otherwise I wouldn't bother.

By barbfeick on May 1, 2009

No, you should correct them and educate everyone.

"Someone could die from my recommendations?"

I recommend that if you had reacted to peanuts severely that you don't assume that you are suddenly safe if you do not react from a new allergy test.

I recommend that if your child has a peanut allergy that you cook from scratch and avoid all foods made by others as much as possible.

I recommend that you pay attention to one's entire diet and cut out sugar, artificial flavors and colors.

I recommend that people rally and end the trade secret protection that vaccine manufactures have. Doctors should know if peanut products are being used in the culture medium or if peanut oil is used in the adjuvant.

I am posting on this site because I was invited to do so by the site owner. I provide an alternative viewpoint that gets you excited enough to post replies.

If I post something that is totally wrong, you should post a nice lengthy answer that points out exactly what is incorrect. That way you educate lots of people and not just me.

By Catherine95 on Apr 29, 2009

I`m a physician and barbfeick`s posts are full of incorrect information. Please disregard them.

By barbfeick on Apr 30, 2009

"Skin and CAP RAST blood tests are both about 50% accurate for positive results and over 90% accurate for negative."

These test for IgE only? I am familiar with the RAST, that has been around for a while. I had gone to my allergist requesting a Rast test a few years ago. He told me the test was garbage. Then a year later, I went to the same allergist and had it done. He changed his mind about the value of the test. Is the CAP RAST different from the original RAST?

If 10 items tested positive, then I'm really only allergic to 5 items?

If 10 items tested negative then there is still one of those items that I am still allergic to? If 100 items test negative then I'm still allergic to 10...

Really isn't a good idea to totally rely on tests. Food diary and eating fewer foods at a time so you can pinpoint a food reaction. Hard to know what you react to in a meal if you ate 20 different foods.

By barbfeick on May 30, 2009

Found this study on the Net:

http://www.medscape.com/medline/abstract/9920216?src=emed_ckb_ref_0

Interpreting skin prick tests in the evaluation of food allergy in children...

BACKGROUND: ...Efforts to standardize SPT reagents and procedures have been made, but the accuracies of different recording techniques have not been clearly defined. The aim of this study was to compare different SPT recording methods with the outcome of oral food challenge...

PATIENTS AND METHODS: Ch...The wheal reactions were recorded by two different methods: first by measuring the largest diameter of the wheal and the diameter orthogonal to it (mean wheal diameter), and second by recording the surface area of the wheal with a hand-held scanner....

CONCLUSIONS: Skin prick tests are a useful procedure for evaluating clinical reactivity to egg, milk, peanut and wheat, but not to soy. While the size of the SPT wheals may be interpreted utilizing mean diameter or surface area cut-offs, the predictive values of these measurement methods were no better than the commonly utilized grading method where a positive skin test was recorded as a mean wheal diameter 3 mm greater than the negative control.

===================================================== More information is available at:

http://www.worldallergy.org/professional/allergic_diseases_center/allergy_diagnostic/

Standardized forms have been developed and are available through the American Academy of Allergy Asthma and Immunology website (for an example AAAAI's Skin Test and Immunotherapy Forms).

But I did not find a chart to interpret the test either.

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