Allergy test - blood vs prick test

DD was diagnosed with a egg allergy via a prick test when she was 6 months old.

Fast forward to another prick test at 2 years old. Not allergic to eggs anymore but yes to Walnuts and Pecans.

Want to get her retested to see if that potentially has changed (after all her egg allergy went away)

Which is more accurate a prick test or a blood test?

I heard blood tests are not as accurate when they are young...she is now 2.5 years old.

I kind of want to do a blood test because they can test for a whole range of items but with the prick test you are limited to a few items (amount of test items they have and the size of her back).

Thanks

Allergy test - blood vs prick test

when you say prick test, you mean skin test?

my son has had 2 blood tests and 2 skin tests. i've been told by my allergist that the skin test gives you a yes or no, reaction seen or not. the blood test (if positive) gives you a number. and they can base your allergy level on that number. i was told that the levels can rise up until they are about 5 years old. his first blood test was at age 2 and the second at 4.

i'm not sure which is more accurate. my son has blood tested positive for peanuts, negative for tree nuts and negative for beef. but skin test positive peanuts, positive tree nuts and positive beef. to be safe, we avoid all foods he has skin tested positive for. we feel you can't be too cautious when it comes to food allergies, but everyone should develop their own plan with their allergist. the explanation my allergist provided was his allergy to tree nuts and beef could be mild, more like a sensitivity. the only true confirmation with an allergy is by a reaction, which we want to avoid. we saw his peanut reaction and that was scary!

i would suggest talking to your allergist, request the blood test and ask them to explain the results and how they could differ from the skin tests. they may recommend waiting a bit on the blood work until levels have stabilized.

i've been on this food allergy journey for over 3 years now and i still don't understand a lot of it. good luck!

Re: Allergy test - blood vs prick test

At two years old their veins might collapse, making it hard to a) get them to sit still b) draw enough blood for a conclusive sample

Re: Allergy test - blood vs prick test

According to DS's allergist, both the the blood test and skin tests give you an idea that generally tells you how severe the allergy is, but does not necessarily predict how bad an allergic reaction would be. Each exposure to an allergen can have a totally different reaction than the previous (i.e. hives one time, anaphylactic another time to the same allergen). So both the blood and skin tests are accurate and either can be done. Blood test is obviously more intrusive, but over quicker and can test for more substances. Skin test gives immediate results, though, with no needles, which children generally hate.

To the original poster, is your child under the care of an allergist? If there are foods that your child is only questionably allergic to, they can do a challenge test in the office.