Delayed reaction to skin test


My daughter has had two skin tests, a year apart. Her reaction to both (ie. red welt) did not appear until hours after the test. Right after the first test, she became very itchy, but that soon passed. The welt on the second test was smaller than the first. Her allergist was not familiar with this delayed reaction and he recommended that we treat her as if she has a peanut allergy (complete with epipen) and retest in a year. Has anyone ever encountered such a reaction? We are from Canada and have not had a RAST test done yet because it isn't covered by the health plan. How could I ever give her peanuts again, anyways??

On May 5, 1999

Hi Janine,

We live in England and I don't know if this will help at all but I thought I would tell you my eldest son's story, which also deals with uncertain peanut tests.

Because of his egg & milk allergies he had range of skin prick tests done when he was 1 year old. This showed up peanut and almond allergies. Now he is 4 years old and we have a new pediatric allergist. New skin test result shows negative to peanuts, very small to almonds and to brazils. Blood test results show very small reaction to some but not all of these. My son has never consumed any nuts and has never had an allergic reaction caused by nuts. His doctor thinks that he might actually be able to eat nuts without having a reaction - that his skin prick tests were false positives. Apparently there are very high numbers of false positives to skin prick tests and clinical histories are much more important.

In order to resolve this James is going to have a food challenge test in the hospital. This means they are going to give him a very little peanut, then a little more and then a little more etc under very very controlled circumstances. I don't know when this will happen (our NHS waiting lists are very long especially for allergy services) but probably somewhere between 6 to 12 months.

This may seem like a drastic course of action but he is potentially ananphlatic to sesame and eggs (seems to be growing out of the milk allergy) and has to avoid kiwi and coconut too, so having one less thing to worry about would be a great blessing.

I guess what I am trying to say is that you need more information. Why was your daughter tested? Had she had a reaction to peanuts? If she did have a reaction to peanuts then the fact that her skin prick test result is technically negative does not matter (it is the first 15 minutes that usually count). She is allergic. But if she has not actually had a reaction to peanuts in the real world then maybe you, like me, have been worrying about an allergy that does not really exist.

This is me at my most optimistic. I fully admit it may all be wishful thinking and both our children may have severe peanut allergies. Without more information we cannot know. And uncertainty is itself very worrying.

Thinking of you,


On May 5, 1999

Holly, thank-you for your response. I really haven't talked to others dealing with potential peanut allergies. Just to clarify...

My daughter first reacted to peanuts at about 13 months with hives around the mouth that quickly came and went. This was after several feedings of peanuts. On advice of the doctor, we held off peanuts until she was 2 years old and tried again. She reacted with hives around the mouth and chest which lasted a couple of days. We then were referred to an allergist for skin tests. Since she has been off peanuts, she has had two cases of mild hives around the mouth after eating "new" foods which I suspect could have contained trace peanuts.

On May 7, 1999

Hi Janine

I think that your daughter pretty obviously has an allergy to peanuts! But maybe her strange skin test results mean she will be one of the few who outgrow it! I really hope so.