What happens after allergy blood test if positive

[Bee3214]

After having an allergic reaction to eggs , my baby is having a blood test to this and nuts. He may also be allergic to nuts but never tried them. Family members are though. I have heard the lge levels can be inaccurate in determining how severe a response is.
I know with eggs they usually grow out of it, and we are reintroducing them just fine. But with nuts, many don’t usually grow out of it. Will they do a good challenge if he is allergic or do we just avoid them altogether?

Likely they will do skin prick tests and possibly once older a food challenge. It is difficult to diagnose allergies if there has never been a reaction to that food.

My DS outgrew allergies to milk and eggs, but showed an allergy to various nuts at first skin prick tests at 13 months (having never had nuts at that point) and had a food challenge at age 11 which confirmed this (still never having had the majority of nuts). His annual blood test and skin prick results had shown about a 90% chance of allergy but we wanted confirmation before he became more independent - not least given he would need to carry his epi pen around himself at senior school.

So I will never know if it’s a severe allergy or not?

It’s difficult to confirm an allergy via blood tests and skin prick tests but with no actual reaction to that food - they can only give a likely diagnosis, and cannot necessarily predict the allergic response.

That’s why we chose to have a food challenge particularly as DS1 was about to go to secondary school.

It’s also difficult to gauge the seriousness of a reaction as it can change over time. The fact that DS1 complained of an itchy tongue and projectile vomited after eating 0.5g of a cashew was enough for them to worry about anaphylaxis in future contact and to prescribe an epi pen.

DS1 was skin pricked annually for 10 years before the food challenge though and they were happy for us to introduce other nuts at home on the basis that the skin prick tests were reducing over time (he is only allergic to cashews and pistachios- very middle class ).